Too Much Iodine Can Be as Bad as Too Little

Iodine toxicity from soy milk and seaweed ingestion is associated with serious thyroid dysfunction.

We report a series of cases of thyroid dysfunction in adults associated with ingestion of a brand of soy milk manufactured with kombu (seaweed), and a case of hypothyroidism in a neonate whose mother had been drinking this milk. We also report two cases of neonatal hypothyroidism linked to maternal ingestion of seaweed made into soup. These products were found to contain high levels of iodine. Despite increasing awareness of iodine deficiency, the potential for iodine toxicity, particularly from sources such as seaweed, is less well recognised.

Some subgroups of reproductive age women in the United States may be at risk for iodine deficiency.

Consuming an adequate amount of iodine during pregnancy is critical for fetal neurologic development. Even a mild deficiency can impair cognitive ability. Important sources of iodine in the United States include dairy products and iodized salt. Although the U.S. population has traditionally been considered iodine sufficient, median urinary iodine concentrations (UIC) have decreased 50% since the 1970s. We analyzed 2001-2006 NHANES data from urine iodine spot tests for pregnant (n = 326), lactating (n = 53), and nonpregnant, nonlactating (n = 1437) women of reproductive age (15-44 y). We used WHO criteria to define iodine sufficiency (median UIC: 150-249 microg/L among pregnant women; >or=100 microg/L among lactating women; and 100-199 microg/L among nonpregnant, nonlactating women). The iodine status of pregnant women was borderline sufficient (median UIC = 153 microg/L; 95% CI = 105-196), while lactating (115 microg/L; 95% CI = 62-162) and nonpregnant, nonlactating (130 microg/L; 95% CI = 117-140) women were iodine sufficient. Dairy product consumption was an important contributor to iodine status among both pregnant and nonpregnant, nonlactating women, and those who do not consume dairy products may be at risk for iodine deficiency. Although larger samples are needed to confirm these findings, these results raise concerns about the iodine status of pregnant women and women of reproductive age who are not consuming dairy products. Iodine levels among U.S. women should be monitored, particularly among subgroups at risk for iodine deficiency.

Cretinism revisited.

Endemic cretinism includes two syndromes: a more common neurological disorder with brain damage, deaf mutism, squint and spastic paresis of the legs and a less common syndrome of severe hypothyroidism, growth retardation and less severe mental defect. Both conditions are due to dietary iodine deficiency and can be prevented by correction of iodine deficiency before pregnancy. Endemic cretinism is now included in the spectrum of the effects of iodine deficiency in a population termed the 'iodine deficiency disorders (IDDs)', which also includes a wide range of lesser degrees of cognitive defect that can be prevented by the correction of iodine deficiency. Iodine deficiency is now recognised by the World Health Organization (WHO) as the most common preventable cause of brain damage with in excess of 2 billion at risk from 130 countries. A global United Nations (UN) programme of prevention has achieved 68% household usage of iodised salt by the year 2000 compared with less than 20% prior to 1990. Copyright 2009 Elsevier Ltd. All rights reserved.

Iodine-induced neonatal hypothyroidism secondary to maternal seaweed consumption: a common practice in some Asian cultures to promote breast milk s...

Mild iodine deficiency is a recognised problem in Australia and New Zealand. However, iodine excess can cause hypothyroidism in some infants. We highlight two cases which illustrate the risks of excess dietary iodine intake during pregnancy and breastfeeding. They also describe a cultural practice of consuming seaweed soup to promote breast milk supply. Although most attention recently has been on the inadequacy of iodine in Australian diets, the reverse situation should not be overlooked. Neither feast nor famine is desirable. © 2011 The Authors. Journal of Paediatrics and Child Health © 2011 Paediatrics and Child Health Division (Royal Australasian College of Physicians).

Too much of too little: xylitol, an unusual trigger of a chronic metabolic hyperchloremic acidosis.

Homeopathic globules are frequently used in children as a first-line treatment. Most of these globules are coated with sugar substitutes like xylitol; these substitutes are known for their laxative effect. Our patient shows that consumption of globules coated with xylitol does not have only laxative effects. It may cause indeed considerable weight loss and life-threatening enteral bicarbonate loss by diarrhea when overdosed in an infant.

Variability of iodine content in common commercially available edible seaweeds.

Dietary seaweeds, common in Asia and in Asian restaurants, have become established as part of popular international cuisine. To understand the possibility for iodine-induced thyroid dysfunction better, we collected samples of the most common dietary seaweeds available from commercial sources in the United States, as well as harvester-provided samples from Canada, Tasmania, and Namibia. Altogether, 12 different species of seaweeds were analyzed for iodine content, and found to range from 16 microg/g (+/-2) in nori (Porphyra tenera) to over 8165 +/- 373 microg/g in one sample of processed kelp granules (a salt substitute) made from Laminaria digitata. We explored variation in preharvest conditions in a small study of two Namibian kelps (Laminaria pallida and Ecklonia maxima), and found that iodine content was lowest in sun-bleached blades (514 +/- 42 microg/g), and highest amount in freshly cut juvenile blades (6571 +/- 715 microg/g). Iodine is water-soluble in cooking and may vaporize in humid storage conditions, making average iodine content of prepared foods difficult to estimate. It is possible some Asian seaweed dishes may exceed the tolerable upper iodine intake level of 1100 microg/d.

An epidemiologic study of thyroid cancer in Hawaii.

A population-based case-control interview study was designed to test the hypothesis that dietary iodine or the consumption of goitrogenic vegetables increases the risk of thyroid cancer. A total of 191 histologically confirmed cases (64 percent female) and 441 matched controls from five ethnic groups in Hawaii were available for analysis. Among women, intake of seafood (especially shellfish), harm ha (a fermented fish sauce), and dietary iodine were associated with an increased risk of cancer, whereas consumption of goitrogenic (primarily cruciferous) vegetables was associated with a decreased risk. Non-dietary risk factors included miscarriage (especially at first pregnancy), use of fertility drugs, family history of thyroid disease, obesity, and work as a farm laborer. The odds ratio for the combined effect of a high iodine intake and a first-pregnancy miscarriage was 4.8 (95 percent confidence interval [CI] = 1.2-19.2); and for high iodine intake and use of fertility drugs 7.3 (95 percent CI = 1.5-34.5). Among men, positive associations were found for obesity, work as a farm laborer, and a past history of benign thyroid disease. Although this study identified several dietary and non-dietary risk factors for thyroid cancer, it could not fully explain the exceptionally high incidence rates among Filipino women in Hawaii.

Iodine and thyroid cancer risk among women in a multiethnic population: the Bay Area Thyroid Cancer Study.

Research on the relationship between iodine exposure and thyroid cancer risk is limited, and the findings are inconclusive. In most studies, fish/shellfish consumption has been used as a proxy measure of iodine exposure. The present study extends this research by quantifying dietary iodine exposure as well as incorporating a biomarker of long-term (1 year) exposure, i.e., from toenail clippings. This study is conducted in a multiethnic population with a wide variation in thyroid cancer incidence rates and substantial diversity in exposure. Women, ages 20-74, residing in the San Francisco Bay Area and diagnosed with thyroid cancer between 1995 and 1998 (1992-1998 for Asian women) were compared with women selected from the general population via random digit dialing. Interviews were conducted in six languages with 608 cases and 558 controls. The established risk factors for thyroid cancer were found to increase risk in this population: radiation to the head/neck [odds ratio (OR), 2.3; 95% confidence interval (CI), 0.97-5.5]; history of goiter/nodules (OR, 3.7; 95% CI, 2.5-5.6); and a family history of proliferative thyroid disease (OR, 2.5; 95% CI, 1.6-3.8). Contrary to our hypothesis, increased dietary iodine, most likely related to the use of multivitamin pills, was associated with a reduced risk of papillary thyroid cancer. This risk reduction was observed in "low-risk" women (i.e., women without any of the three established risk factors noted above; OR, 0.53; 95% CI, 0.33-0.85) but not in "high-risk" women, among whom a slight elevation in risk was seen (OR, 1.4; 95% CI, 0.56-3.4). However, no association with risk was observed in either group when the biomarker of exposure was evaluated. In addition, no ethnic differences in risk were observed. The authors conclude that iodine exposure appears to have, at most, a weak effect on the risk of papillary thyroid cancer.

Iodine Status and Thyroid Function of Boston-Area Vegetarians and Vegans

Context: Adequate dietary iodine is required for normal thyroid function. The iodine status and thyroid function of U.S. vegetarians and vegans have not been previously studied. Environmental perchlorate and thiocyanate (inhibitors of thyroid iodine uptake) exposures may adversely affect thyroid function. Objective: The objective of the study was to assess the iodine status and thyroid function of U.S. vegetarians (consume plant based products, eggs, milk; abstain from meat, poultry, fish, shellfish) and vegans (avoid all animal products) and whether these may be affected by environmental perchlorate and thiocyanate exposures. Design and Setting: This was a cross-sectional assessment of urinary iodine, perchlorate, and thiocyanate concentrations and serum thyroid function in Boston-area vegetarians and vegans. Subjects: One hundred forty-one subjects (78 vegetarians, 63 vegans) were recruited; one vegan was excluded. Results: Median urinary iodine concentration of vegans (78.5 μg/liter; range 6.8–964.7 μg/liter) was lower than vegetarians (147.0 μg/liter; range 9.3–778.6 μg/liter) (P < 0.01). Adjusted for cigarette smoking (confirmed by urinary cotinine levels) and thiocyanate-rich food consumption, median urinary thiocyanate concentration of vegans (630 μg/liter; range 108-3085 μg/liter) was higher than vegetarians (341 μg/liter; range 31–1963 μg/liter) (P < 0.01). There were no between-group differences in urinary perchlorate concentrations (P = 0.75), TSH (P = 0.46), and free T4 (P = 0.77). Urinary iodine, perchlorate, and thiocyanate levels were not associated with TSH (P = 0.59) or free T4 (P = 0.14), even when adjusted for multiple variables. Conclusions: U.S. vegetarians are iodine sufficient. U.S. vegans may be at risk for low iodine intake, and vegan women of child-bearing age should supplement with 150 μg iodine daily. Environmental perchlorate and thiocyanate exposures are not associated with thyroid dysfunction in these groups.

Seaweed consumption and the risk of thyroid cancer in women: the Japan Public Health Center-based Prospective Study.

Iodine is a suspected risk factor for thyroid cancer. Seaweed accounts for about 80% of Japanese people's iodine intake. We examined the association between seaweed consumption and the risk of thyroid cancer in Japanese women. Women participating in the Japan Public Health Center-based Prospective Study (n=52 679; age: 40-69 years) were followed up for a mean of 14.5 years; 134 new thyroid cancer cases, including 113 papillary carcinoma cases, were identified. Seaweed consumption was assessed using a food-frequency questionnaire and divided into three categories: 2 days/week or less (reference); 3-4 days/week; and almost daily. The Cox proportional hazards model was applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Seaweed consumption was clearly associated with an increased risk of papillary carcinoma (HR for almost daily consumption compared with 2 days/week or less=1.71; 95% CI: 1.01-2.90; trend P=0.04). After stratification for menopausal status, an increased risk was observed in postmenopausal women (papillary carcinoma HR for almost daily consumption compared with 2 days/week or less=3.81, 95% CI: 1.67-8.68; trend P<0.01), but not in premenopausal women (HR=0.91, 95% CI: 0.44-1.91; trend P=0.76). This study identified a positive association between seaweed consumption and the risk of thyroid cancer (especially for papillary carcinoma) in postmenopausal women.

Immune potentiation of ultrafine dietary particles in normal subjects and patients with inflammatory bowel disease.

Various specific and non-specific environmental factors have been associated with the induction and/or exacerbation of disease activity in patients with Crohn's disease and ulcerative colitis. One such factor is the potential role of ingested ultrafine particles. In fact, based on a Western diet, recent data suggest that more than 10(12)ultrafine particles are ingested per person every day. These microparticles have been considered inert although they adsorb endogenous constituents of the intestinal lumen and are taken up by human intestinal lymphoid aggregates. Based on these observations, we determined whether one such dietary microparticle, titanium dioxide (TiO(2)), alters intestinal cell responsiveness to lipopolysaccharide (LPS) using colonic biopsy specimens from 28 patients with ulcerative colitis, 21 with Crohn's disease, and 36 healthy controls. These samples, as well as peripheral blood mononuclear cells when available, were incubated alone (control), or with either (a) LPS (1-2,000 ng/ml), (b) TiO(2)(5 microg/ml) or (c) LPS (1 ng/ml) adsorbed to TiO(2)(5 microg/ml). In each case, the levels of interleukin 1 (IL-1) produced in these assays were quantitated by bioassay and by ELISA. Interestingly, there was dramatic stimulation of peripheral blood mononuclear cells using the TiO(2)-LPS conjugate, with values 30-60-fold above controls and only minor stimulation with LPS or TiO(2)alone. In intestinal organ cultures there was no increase in IL-1 secretion when challenged with TiO(2)alone or with up to 2,000 ng/ml LPS. However, the TiO(2)-LPS conjugate produced a two-to-three-fold, significant increase in the intestinal secretion of IL-1. Our data demonstrate that ultrafine dietary particles are not immunologically inert and may be important adjuncts in overcoming normal gut cell hyporesponsiveness to endogenous luminal molecules. This may be particularly relevant to patients with inflammatory bowel disease where there is abnormal intestinal permeability. Copyright 2000 Academic Press.

Povidone iodine-induced overt hypothyroidism in a patient with prolonged habitual gargling: urinary excretion of iodine after gargling in normal su...

Iodine-induced hypothyroidism that develops in patients who gargle routinely with povidone iodine is well known. Usually the hypothyroidism is mild and resolves spontaneously upon cessation of gargling. Here, we report a 63-year-old patient with overt hypothyroidism that developed due to habitual gargling with povidone iodine for more than 10 years. The urinary excretion of iodine was estimated to be greater than 5 mg/day, based on values obtained from 18 normal subjects who gargled three times a day (4.6+/-2.1 mg, mean+/-SD). After discontinuation of the gargling, the patient has been euthyroid for more than 10 months.

An unexpected mortality increase in the United States follows arrival of the radioactive plume from Fukushima: is there a correlation?

The multiple nuclear meltdowns at the Fukushima plants beginning on March 11, 2011, are releasing large amounts of airborne radioactivity that has spread throughout Japan and to other nations; thus, studies of contamination and health hazards are merited. In the United States, Fukushima fallout arrived just six days after the earthquake, tsunami, and meltdowns. Some samples of radioactivity in precipitation, air, water, and milk, taken by the U.S. government, showed levels hundreds of times above normal; however, the small number of samples prohibits any credible analysis of temporal trends and spatial comparisons. U.S. health officials report weekly deaths by age in 122 cities, about 25 to 35 percent of the national total. Deaths rose 4.46 percent from 2010 to 2011 in the 14 weeks after the arrival of Japanese fallout, compared with a 2.34 percent increase in the prior 14 weeks. The number of infant deaths after Fukushima rose 1.80 percent, compared with a previous 8.37 percent decrease. Projecting these figures for the entire United States yields 13,983 total deaths and 822 infant deaths in excess of the expected. These preliminary data need to be followed up, especially in the light of similar preliminary U.S. mortality findings for the four months after Chernobyl fallout arrived in 1986, which approximated final figures.

Sodium and potassium intakes among US adults: NHANES 2003–2008

Background: The American Heart Association (AHA), Institute of Medicine (IOM), and US Departments of Health and Human Services and Agriculture (USDA) Dietary Guidelines for Americans all recommend that Americans limit sodium intake and choose foods that contain potassium to decrease the risk of hypertension and other adverse health outcomes. Objective: We estimated the distributions of usual daily sodium and potassium intakes by sociodemographic and health characteristics relative to current recommendations. Design: We used 24-h dietary recalls and other data from 12,581 adults aged ≥20 y who participated in NHANES in 2003–2008. Estimates of sodium and potassium intakes were adjusted for within-individual day-to-day variation by using measurement error models. SEs and 95% CIs were assessed by using jackknife replicate weights. Results: Overall, 99.4% (95% CI: 99.3%, 99.5%) of US adults consumed more sodium daily than recommended by the AHA (<1500 mg), and 90.7% (89.6%, 91.8%) consumed more than the IOM Tolerable Upper Intake Level (2300 mg). In US adults who are recommended by the Dietary Guidelines to further reduce sodium intake to 1500 mg/d (ie, African Americans aged ≥51 y or persons with hypertension, diabetes, or chronic kidney disease), 98.8% (98.4%, 99.2%) overall consumed >1500 mg/d, and 60.4% consumed >3000 mg/d—more than double the recommendation. Overall, <2% of US adults and ∼5% of US men consumed ≥4700 mg K/d (ie, met recommendations for potassium). Conclusion: Regardless of recommendations or sociodemographic or health characteristics, the vast majority of US adults consume too much sodium and too little potassium.

Zinc and multi-mineral supplementation should mitigate the pathogenic impact of cadmium exposure.

High-level cadmium (Cd) exposure has long been known to induce nephropathy, severe osteoporosis, and fractures in humans. More recent epidemiology, however, reveals that, in populations not known to have important industrial exposure to this heavy metal, high-normal blood or urine Cd levels correlate with increased risk for vascular disorders, cancers, diabetes, and total mortality, as well as osteoporosis and nephropathy. Since these disorders appear unlikely to expedite Cd absorption, and since Cd has promoted these pathologies in rodent studies, it seems reasonable to conclude that Cd is an important mediating risk factor for these disorders in humans. Avoiding tobacco smoke or frequent ingestion of shellfish or organ meats can lessen humans exposure to Cd, but the chief dietary sources of Cd are plant-derived foods - green leafy vegetables, whole grains, tubers, and root vegetables - typically recommended for their health-supportive properties; indeed, among non-smokers, vegans tend to have the highest Cd body burden. Fortunately, iron sufficiency and ample dietary intakes of calcium, magnesium, and zinc can impede absorption of dietary Cd, both by down-regulating intestinal expression of mineral transporters, and by directly competing with Cd for access to these transporters. Correction of iron deficiency appears to be of particular importance for controlling Cd absorption. Moreover, zinc supplementation can counteract the toxicity of Cd already in the body via induction of metallothionein, which binds Cd avidly via its sulfhydryl groups; so long as it remains sequestered in this form, Cd is innocuous. Zinc supplementation may in any case be recommendable, as optimal zinc status exerts protective anti-inflammatory, antioxidant, and immunosupportive effects. Inasmuch as the toxicity of Cd appears to be mediated in large part by oxidative stress, ingestion of spirulina, lipoic acid, melatonin, and N-acetylcysteine may also have potential for mitigating the risk associated with Cd exposure, as suggested by rodent studies. Hence, although Cd may prove to be a major risk factor for morbidity and mortality in humans, practical strategies for limiting its absorption and pathogenic impact are at hand. Copyright © 2012 Elsevier Ltd. All rights reserved.

Heavy metals in commercial fish in New Jersey.

Levels of contaminants in fish are of particular interest because of the potential risk to humans who consume them. While attention has focused on self-caught fish, most of the fish eaten by the American public comes from commercial sources. We sampled 11 types of fish and shellfish obtained from supermarkets and specialty fish markets in New Jersey and analyzed them for arsenic, cadmium, chromium, lead, manganese, mercury, and selenium. We test the null hypothesis that metal levels do not vary among fish types, and we consider whether the levels of any metals could harm the fish themselves or their predators or pose a health risk for human consumers. There were significant interspecific differences for all metals, and no fish types had the highest levels of more than two metals. There were few significant correlations (Kendall tau) among metals for the three most numerous fish (yellowfin tuna, bluefish, and flounder), the correlations were generally low (below 0.40), and many correlations were negative. Only manganese and lead positively were correlated for tuna, bluefish, and flounder. The levels of most metals were below those known to cause adverse effects in the fish themselves. However, the levels of arsenic, lead, mercury, and selenium in some fish were in the range known to cause some sublethal effects in sensitive predatory birds and mammals and in some fish exceeded health-based standards. The greatest risk from different metals resided in different fish; the species of fish with the highest levels of a given metal sometimes exceeded the human health guidance or standards for that metal. Thus, the risk information given to the public (mainly about mercury) does not present a complete picture. The potential of harm from other metals suggests that people not only should eat smaller quantities of fish known to accumulate mercury but also should eat a diversity of fish to avoid consuming unhealthy quantities of other heavy metals. However, consumers should bear in mind that standards have a margin of safety.

Death by polonium-210: lessons learned from the murder of former Soviet spy Alexander Litvinenko.

The medical response to radiation--whether the result of radiological warfare, terrorist deployment of improvised radiation dispersal weapons, political assassination, occupational or industrial accidents or the medically radiated patient remains one of the least taught among all disciplines within medical education. In the aftermath of 9/11 among medical vulnerabilities to toxicant threats, of all the categories of weapons of mass destruction (WMD)--whether using the CBRNE (chemical, biological, radiological, nuclear, explosive) or NBC (nuclear, biological, chemical) acronym--radiation is the least taught in professional schools, responder cultures or civil preparedness organizations. To date, few health care professionals (HCP) possess the fundamental knowledge or skills to identify and diagnose, let alone treat a radiation victim; this vulnerability made even more obvious in the aftermath of the high profile assassination of former Russian agent Alexander Litvinenko. He was poisoned with Polonium210. Radioactive substances are ubiquitous with radiation sources being in or transported through virtually every region nationwide. It is essential to increase preparedness among community and rural health care facilities as well as urban and university hospitals. Managing radiation injuries effectively requires access to specialized equipment and expertise. Radiation sickness is progressive and may require acute, critical and long-term care throughout the course of illness. Regardless of the source, preparedness rests upon acknowledging a threat exists and dedicating the resources to address the risks including the enhancement of training and equipment. Mass or individual exposures to radiation present unique challenges to the entire response continuum from law enforcement, first responders and emergency medical care. Increased education about and practice in responding to radiological threats is essential to enhance preparedness.

Arsenic in seaweed--forms, concentration and dietary exposure.

This study has measured the content of total and inorganic forms of arsenic in seaweed available on retail sale for consumption, to provide data for dietary exposure estimates and to support advice to consumers. A total of 31 samples covering five varieties of seaweed were collected from various retail outlets across London and the internet. All of the samples were purchased as dried product. For four of the five varieties, soaking was advised prior to consumption. The recommended method of preparation for each individual sample was followed, and total and inorganic arsenic were analysed both before and after preparation. The arsenic remaining in the water used for soaking was also measured. Arsenic was detected in all samples with total arsenic at concentrations ranging from 18 to 124 mg/kg. Inorganic arsenic, which can cause liver cancer, was only found in the nine samples of hijiki seaweed that were analysed, at concentrations in the range 67-96 mg/kg. Other types of seaweed were all found to contain less than 0.3mg/kg inorganic arsenic, which was the limit of detection for the method used. Since consumption of hijiki seaweed could significantly increase dietary exposure to inorganic arsenic, the UK Food Standards Agency (FSA) issued advice to consumers to avoid eating it.

Oxidative stress in radiology staff.

Excessive production of reactive oxygen species has been observed following acute and chronic exposure to radiation in animal models which can lead to several detrimental and irreversible outcomes in vital organs. Aim of this study was to determine the oxidative stress status in radiology unit workers which are exposed to persistent low-dose radiation. METHODS: : A group of 32 radiology unit employees along with 32 sex- and age-matched hospital workers, not exposed to low-dose radiation were recruited from two separate hospitals for the study. Exposed subjects showed higher levels of lipid peroxidation (P=0.009), total antioxidant capacity (P=0.0006) and thiol groups (P=0.03). It is concluded that occupationally exposed individuals are oxidatively stressed and precautions such as antioxidant therapy seems reasonable.

Pacific bluefin tuna transport Fukushima-derived radionuclides from Japan to California

The Fukushima Dai-ichi release of radionuclides into ocean waters caused significant local and global concern regarding the spread of radioactive material. We report unequivocal evidence that Pacific bluefin tuna, Thunnus orientalis, transported Fukushima-derived radionuclides across the entire North Pacific Ocean. We measured γ-emitting radionuclides in California-caught tunas and found 134Cs (4.0 ± 1.4 Bq kg−1) and elevated 137Cs (6.3 ± 1.5 Bq kg−1) in 15 Pacific bluefin tuna sampled in August 2011. We found no 134Cs and background concentrations (∼1 Bq kg−1) of 137Cs in pre-Fukushima bluefin and post-Fukushima yellowfin tunas, ruling out elevated radiocesium uptake before 2011 or in California waters post-Fukushima. These findings indicate that Pacific bluefin tuna can rapidly transport radionuclides from a point source in Japan to distant ecoregions and demonstrate the importance of migratory animals as transport vectors of radionuclides. Other large, highly migratory marine animals make extensive use of waters around Japan, and these animals may also be transport vectors of Fukushima-derived radionuclides to distant regions of the North and South Pacific Oceans. These results reveal tools to trace migration origin (using the presence of 134Cs) and potentially migration timing (using 134Cs:137Cs ratios) in highly migratory marine species in the Pacific Ocean.

Polybrominated diphenyl ethers (PBDEs), hydroxylated PBDEs (OH-PBDEs), and measures of thyroid function in second trimester pregnant women in California

Prenatal exposure to polybrominated diphenyl ethers (PBDEs) may disrupt thyroid function and contribute to adverse neurodevelopmental outcomes. We conducted a pilot study to explore the relationship between serum concentrations of lower-brominated PBDEs (BDE-17 to -154), higher-brominated PBDEs (BDE-183 to -209), and hydroxylated PBDE metabolites (OH-PBDEs) with measures of thyroid function in pregnant women. Concentrations of PBDEs, OH-PBDEs, thyroid-stimulating hormone (TSH), total thyroxine (T4), and free T4 were measured in serum samples collected between 2008 and 2009 from 25 second trimester pregnant women in California. Median concentrations of lower-brominated PBDEs and OH-PBDEs were the highest reported to date in pregnant women. Median concentrations of BDE-47 and the sum of lower-brominated PBDEs (ΣPBDE5) were 43.1 ng/g lipid and 85.8 ng/g lipid; and 0.084 ng/mL for the sum of OH-PBDEs (ΣOH-PBDE4). We observed a positive association between the weighted sum of chemicals known to bind to transthyretin (ΣTTR binders) and TSH levels. We also found positive associations between TSH and ΣPBDE5, ΣOH-PBDE4, BDE-47, BDE-85, 5-OH-BDE47, and 4′-OH-BDE49; and an inverse association with BDE-207. Relationships with free and total T4 were weak and inconsistent. Our results indicate that PBDE exposures are elevated in pregnant women in California, and suggest a relationship with thyroid function. Further investigation is warranted to characterize the risks of PBDE exposures during pregnancy.

Update on the biological effects of ionizing radiation, relative dose factors and radiation hygiene.

Diagnostic imaging is an indispensable part of contemporary medical and dental practice. Over the last few decades there has been a dramatic increase in the use of ionizing radiation for diagnostic imaging. The carcinogenic effects of high-dose exposure are well known. Does diagnostic radiation rarely cause cancer? We don't know but we should act as if it does. Accordingly, dentists should select patients wisely - only make radiographs when there is patient-specific reason to believe there is a reasonable expectation the radiograph will offer unique information influencing diagnosis or treatment. Low-dose examinations should be made: intraoral imaging - use fast film or digital sensors, thyroid collars, rectangular collimation; panoramic and lateral cephalometric imaging - use digital systems or rare-earth film screen combinations; and cone beam computed tomography - use low-dose machines, restrict field size to region of interest, reduce mA and length of exposure arc as appropriate. © 2012 Australian Dental Association.

Gastrointestinal safety of NSAIDs and over-the-counter analgesics.

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used. It is well recognised that they may adversely cause damage throughout the gastrointestinal tract and aggravate pre-existing disease. Their side effects on the upper gastrointestinal tract can be assessed by various means; each study type has different clinical connotations. Short-term use (less than 14 days) demonstrates dose-dependent damage of prescribed NSAIDs; the damage is proportional to the acidity of the drugs and not seen with Cyclooxygenase-2 (COX-2) selective inhibitors that have a pKa over 7.0. There have not been any serious outcomes, such as bleeding or perforation in these studies, and Helicobacter pylori (HP) plays no role in this damage. Long-term (3 months or more) endoscopy studies in patients show ulcer rates from 15%-35% with the various NSAIDs, but serious outcomes are exceedingly rare. Epidemiological studies show an association between NSAID intake and serious events. Ibuprofen is consistently at the lower end of toxicity rankings, whereas ketorolac and azapropazone are the worst. The risk of bleeding is increased with advancing age, presence of HP, previous history of bleeding, anticoagulant use, etc. The mega-trials show that COX-2 selective agents halve the bleeding episodes, but NSAID-induced gastric bleeding is very rare usually, less than 1 in 200 subjects taking them for a year. Seventy percent of patients develop NSAID-enteropathy, which is associated with intestinal blood and protein loss and rarely strictures. Over-the-counter (OTC) use of ibuprofen and diclofenac is associated with symptomatic gastrointestinal side effects comparable with placebo. Ibuprofen is shown to be remarkably well tolerated at OTC doses in a number of studies. There are recent studies to suggest that OTC NSAIDs should be taken on a fasting stomach, not with food as commonly advocated. © 2012 Blackwell Publishing Ltd.

Titanium Dioxide Nanoparticles in Food and Personal Care Products

Titanium dioxide is a common additive in many food, personal care, and other consumer products used by people, which after use can enter the sewage system, and subsequently enter the environment as treated effluent discharged to surface waters or biosolids applied to agricultural land, incinerated wastes, or landfill solids. This study quantifies the amount of titanium in common food products, derives estimates of human exposure to dietary (nano-) TiO2, and discusses the impact of the nanoscale fraction of TiO2 entering the environment. The foods with the highest content of TiO2 included candies, sweets and chewing gums. Among personal care products, toothpastes and select sunscreens contained 1% to >10% titanium by weight. While some other crèmes contained titanium, despite being colored white, most shampoos, deodorants, and shaving creams contained the lowest levels of titanium (<0.01 μg/mg). For several high-consumption pharmaceuticals, the titanium content ranged from below the instrument detection limit (0.0001 μg Ti/mg) to a high of 0.014 μg Ti/mg. Electron microscopy and stability testing of food-grade TiO2 (E171) suggests that approximately 36% of the particles are less than 100 nm in at least one dimension and that it readily disperses in water as fairly stable colloids. However, filtration of water solubilized consumer products and personal care products indicated that less than 5% of the titanium was able to pass through 0.45 or 0.7 μm pores. Two white paints contained 110 μg Ti/mg while three sealants (i.e., prime coat paint) contained less titanium (25 to 40 μg Ti/mg). This research showed that while many white-colored products contained titanium, it was not a prerequisite. Although several of these product classes contained low amounts of titanium, their widespread use and disposal down the drain and eventually to WWTPs deserves attention. A Monte Carlo human exposure analysis to TiO2 through foods identified children as having the highest exposures because TiO2 content of sweets is higher than other food products, and that a typical exposure for a US adult may be on the order of 1 mg Ti per kilogram body weight per day. Thus, because of the millions of tons of titanium based white pigment used annually, testing should focus on food-grade TiO2 (E171) rather than that adopted in many environmental health and safety tests (i.e., P25), which is used in much lower amounts in products less likely to enter the environment (e.g., catalyst supports, photocatalytic coatings).

The risks of copper toxicity contributing to cognitive decline in the aging population and to Alzheimer's disease.

It is a pleasure and an honor to contribute a paper to a special issue of the Journal of the American College of Nutrition honoring Stanley Wallach and Pearl Small. In this brief review I advance the hypothesis that copper toxicity is the major cause of the epidemic of mild cognitive impairment and Alzheimer's disease engulfing our aging population. This epidemic is recent, exploding in the last 50-60 years. The disease was virtually unknown 100 years ago. And it involves only developed countries that use copper plumbing. Something in our environment associated with development is poisoning the minds of our aged. The epidemic is associated with the use of copper plumbing, and the taking of copper in multi-mineral supplements. Food copper (organic copper) is processed by the liver and is transported and sequestered in a safe manner. Inorganic copper, such as that in drinking water and copper supplements, largely bypasses the liver and enters the free copper pool of the blood directly. This copper is potentially toxic because it may penetrate the blood/brain barrier. I review a web of animal and human data that tightens the noose around the hypothesis that copper toxicity is causing the epidemic of Alzeimer's disease and loss of cognition in our aging population.

Aluminium and other elements in selected herbal tea plant species and their infusions.

The determination of Al, B, Cu, Fe, Mn, Ni, P, Zn and Ca, K, Mg by inductively coupled plasma optical emission spectrometry (ICP-OES) and flame atomic absorption spectroscopy (FAAS), respectively, in digests and infusions of Hibiscus sabdariffa (petals), Rosa canina (receptacles), Ginkgo biloba (leaves), Cymbopogon citratus (leaves), Aloe vera (leaves) and Panax ginseng (roots) was carried out in this study. Particular attention has been given to Al and heavy metals for the identification of possible raw material contaminants, their transformation into the infusion and for predicting their eventual role in the human diet during daily consumption. Additionally, Ion Chromatography (IC) speciation of Al in the leachates was carried out. In dry herbs, hibiscus and ginkgo appeared to contain the greatest contents of Al, Fe, K, Mn, Ni, Zn and B, Mg, P, respectively. A. vera contained the highest amount of Ca and highest values of Cu and P were observed in ginseng. In infusions, the topmost concentrations of Al, B, Cu, Fe, P, K, Mn, Ni, Zn were detected in those prepared from hibiscus petals, Ca from aloe leaves and Mg from leaves of ginkgo. According to a possible daily consumption exceeding 1 L, hibiscus decoction was identified as potentially dietetically significant in the content of certain elements. It seems to be possibly one of the top contributors of B from food (up to 5.5±0.2 mg/L). The Mg contained in the infusion (up to 106±5 mg/L) may be a contributor in the attenuation of blood pressure. A high amount of accessible Mn (up to 17.4±1.1 mg/L) can probably have an adverse effect in humans. The total Al allowance (up to 1.2±0.1 mg/L) suggests that no more than 1 L of the hibiscus infusion should be consumed per day by sensitive individuals including pregnant women and should be completely excluded from the diet of children under 6 months of age and children with chronic renal failure. Copyright © 2013 Elsevier Ltd. All rights reserved.

Pediatric CT research elevates public health concerns: low-dose radiation issues are highly politicized.

This article presents an analysis of issues related to low-dose radiation, with a focus on pediatric computed tomography (CT). It references several early studies that are seldom quoted in radiation research papers, then quantifies the excess lifetime fatal cancer yield attributable to an estimated 6.5 million pediatric abdominal CT scans. The authors highlight an important policy document issued jointly by the National Cancer Institute and the Society for Pediatric Radiology--specifically, its conclusion that a small dose from CT represents "a public health concern." Finally, the article identifies several contentious issues and proposes policy initiatives that, if implemented, could result in significant reductions of future radiogenic cancers and chronic injuries. The authors call for discussions between professional radiology societies and public interest health organizations, thereby involving all stakeholders.

Diet and nutrients are contributing factors that influence blood cadmium levels.

Studies suggested the intake of Cd from diet can be approximately equivalent to that from smoking. Moreover, a mutual metabolic influence between Cd and nutrients has been reported. The purpose of this study was to evaluate the relationship between blood cadmium concentration (BCdC) and food consumption, nutrients intake (Ca, Fe, Zn, vitamin C, and vitamin D), tobacco smoking, and some other variables (age, body mass index, and residence) in 243 adults living in the Italian island of Sardinia (Sassari Province). Specifically, we hypothesized that offal consumption contributes to Cd intakes and blood levels. The BCdC was quantified by graphite furnace atomic absorption spectrometry, and information on personal data was collected through questionnaires. Smoke significantly contributed to the BCdC (P < .001). Nonsmoker subjects who eat offal showed significantly higher BCdC (P = .04). Moreover, slightly higher BCdCs were also observed in nonsmoker subjects who eat rice, fish, and bread. The BCdC positively correlated with age of subjects (r = 0.144; P = .025) and offal daily intake in nonsmokers (r = 0.393; P < .001). The intake of Ca was negatively correlated (r = -0.281; P = .001) with the BCdC in females. The multiple linear regression analysis showed smoking > consumption of offal > body mass index ≈ age as the most important risk factors for the BCdC in the selected population. Copyright © 2011 Elsevier Inc. All rights reserved.

The experience of Japan as a clue to the etiology of breast and ovarian cancers: relationship between death from both malignancies and dietary prac...

Although breast and ovarian cancers are rare in Japan compared with other developed countries, the death rates for both are increasing. In Japan, dramatic lifestyle changes occurred after World War II. Over the past 50 years (1947-1997), the age-standardized death rates of breast and ovarian cancers increased about 2- and 4-fold, respectively, and the respective intake of milk, meat, and eggs increased 20-, 10-, and 7-fold. The increase in the annual death rates from breast and ovarian cancers might be due to the lifestyle changes (increased consumption of animal-derived food) that occurred after 1945. Among the food, milk and dairy products should receive particular attention since they contain considerable amounts of estrogens.

Seaweed prevents breast cancer?

To investigate the chemopreventive effects of seaweed on breast cancer, we have been studying the relationship between iodine and breast cancer. We found earlier that the seaweed, wakame, showed a suppressive effect on the proliferation of DMBA (dimethylbenz(a)anthracene)-induced rat mammary tumors, possibly via apoptosis induction. In the present study, powdered mekabu was placed in distilled water, and left to stand for 24 h at 4 degrees C. The filtered supernatant was used as mekabu solution. It showed an extremely strong suppressive effect on rat mammary carcinogenesis when used in daily drinking water, without toxicity. In vitro, mekabu solution strongly induced apoptosis in 3 kinds of human breast cancer cells. These effects were stronger than those of a chemotherapeutic agent widely used to treat human breast cancer. Furthermore, no apoptosis induction was observed in normal human mammary cells. In Japan, mekabu is widely consumed as a safe, inexpensive food. Our results suggest that mekabu has potential for chemoprevention of human breast cancer.

Cadmium in zinc-containing mineral supplements.

Seven zinc-containing dietary supplements were analyzed for zinc (Zn) and cadmium (Cd) by inductively coupled plasma/mass spectrometry (ICP/MS). Cadmium was detected in all samples; however, the amount of Cd per 15 mg Zn (the daily US Recommended Dietary Allowance) varied by over 37-fold (0.039 to 1.46 micrograms Cd/15 mg Zn). Supplements with Zn in the form of a gluconate consistently contained the lowest amounts of Cd. Because Cd is a non-essential potentially toxic element for humans, its concentration in nutritional supplements should be minimized and possibly regulated by government-established standards.

Informed consent and communication of risk from radiological and nuclear medicine examinations: how to escape from a communication inferno

Short abstract Radiological and nuclear medicine examinations confer a definite (albeit low) long term risk of cancer, but patients undergoing such examinations often receive no or inaccurate information about these risks. Picano argues that this disregard of patient autonomy is no longer acceptable and suggests a practicable way of communicating risk

Growth Hormone Receptor Deficiency is Associated With a Major Reduction in Pro-aging Signaling, Cancer and Diabetes in Humans

Life span extending mutations in growth signaling pathways protect against age-dependent DNA damage in yeast and decrease insulin resistance and cancer in mice. To test their effect in humans, we monitored for 22 years Ecuadorian subjects with mutations in the growth hormone receptor gene leading to severe growth hormone receptor (GHR) and IGF-I deficiencies and combined this information with surveys to identify the cause and age of death for subjects who died before this period. The individuals with GHR deficiency (GHRD) exhibited only one non-lethal malignancy and no cases of diabetes, in contrast to 17% cancer and 5% diabetes prevalence in the controls. A possible explanation for the very low incidence of cancer may be revealed by in vitro studies: serum from GHRD subjects reduced DNA breaks but increased apoptosis in human mammary epithelial cells (HMECs) treated with hydrogen peroxide. We also observed reduced insulin concentrations (1.4 μU/ml vs. 4.4μU/ml in unaffected relatives) and a very low homoeostasis model assessment of insulin resistance (HOMA-IR) index (0.34 vs. 0.96 in unaffected relatives) in GHRD individuals, indicating increased insulin sensitivity, which could explain the absence of diabetes in these subjects. Incubation of HMECs with GHRD serum also resulted in reduced expression of RAS, PKA and TOR, and up-regulation of SOD2, changes that promote cellular protection and life span extension in model organisms. These results provide evidence for a role of evolutionarily conserved pathways in promoting aging and diseases in humans and identify a candidate drug target for healthy life span extension.

Aluminium in over-the-counter drugs: risks outweigh benefits?

In the early 1970s, aluminium toxicity was first implicated in the pathogenesis of clinical disorders in patients with chronic renal failure involving bone (renal osteomalacia) or brain tissue (dialysis encephalopathy). Before that time the toxic effects of aluminium ingestion were not considered to be a major concern because absorption seemed unlikely to occur. Meanwhile, aluminium toxicity has been investigated in countless epidemiological and clinical studies as well as in animal experiments and many papers have been published on the subject. It is now commonly acknowledged that aluminium toxicity can be induced by infusion of aluminium-contaminated dialysis fluids, by parenteral nutrition solutions, and by oral exposure as a result of aluminium-containing pharmaceutical products such as aluminium-based phosphate binders or antacid intake. Over-the-counter antacids are the most important source for human aluminium exposure from a quantitative point of view. However, aluminium can act as a powerful neurological toxicant and provoke embryonic and fetal toxic effects in animals and humans after gestational exposure. Despite these facts, the patient information leaflets from European antacids that are available OTC show substantial differences regarding warnings from aluminium toxicity. It seems advisable that all patients should receive the same information on aluminium toxicity from patient information leaflets, in particular with regard to the increased absorption through concomitant administration with citrate-containing beverages and the use of such antacids during pregnancy.

Nonylphenol and octylphenol in human breast milk.

Human milk is the most important form of nourishment for newborn children. Its consumption is strongly recommended by health authorities also for other important advantages. Unfortunately, in the last three decades a great number of investigations have shown the occurrence of several environmental contaminants in human milk, especially those with lipophilic properties. This study investigates the presence of nonylphenol, octylphenol (OP), nonylphenol monoethoxylate (NP1EO) and two octylphenol ethoxylates (OPEOs) (namely OP1EO and OP2EO), in human breast milk of Italian women. NP was the contaminant found at the highest levels with mean concentrations of 32 ng/mL, about two orders of magnitude higher than OP (0.08 ng/mL), OP1EO (0.07 ng/mL) and OP2EO (0.16 ng/mL). In the group of study a positive correlation among fish consumption and levels of NP in the milk was observed, in accordance with the evidence that seafood represents one of the most important sources of exposure to this group of contaminants in Italy. On the basis of the concentrations found in the breast milk samples, a maximum NP daily intake of 3.94 microg/kg/day can be calculated, which is close to the Tolerable Daily Intake (TDI) of 5 microg/kg body weight (bw) proposed by the Danish Institute of Safety and Toxicology. In the cases of OP no TDI is available, but its intake is at least six orders of magnitude lower than the NOAEL of 10 mg/kg/day derived from a two generation study on rats.

The protective effect of the flavonoids on food-mutagen-induced DNA damage in peripheral blood lymphocytes from colon cancer patients.

The food mutagens IQ (2-amino-3-methylimidazo[4,5-f]quinoline) and PhIP (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine) are heterocyclic amines (HCA), generated when heating proteinaceous food. This study investigates the protective potential of the flavonoids quercetin (Q) and rutin (R) against oxidative stress induced in vitro by IQ and PhIP in lymphocytes from healthy individuals and untreated, newly diagnosed colon cancer patients using the Comet assay. In the presence of up to 500μM Q and R, the DNA damage resulting from a high dose of PhIP (75μM) or IQ (150μM) was significantly reduced (P<0.001) to levels comparable to six times lower IQ or 7.5 times lower PhIP doses. Lymphocytes from colon cancer patients had greater baseline DNA damage than those from healthy individuals (P<0.01) and this higher level of damage was also observed throughout in vitro treatment. Except for the >50years of age group and male gender, confounding factors such as smoking, drinking and/or dietary habits were not found to be significant. In conclusion, flavonoids reduced oxidative stress caused by food mutagens in vitro in lymphocytes of healthy individuals and colon cancer patients. Thus, dietary supplementation with flavonoid-rich vegetables and fruits may prove very effective in protecting against oxidative stress. Copyright © 2011 Elsevier Ltd. All rights reserved.

N-Nitroso compounds in the diet.

N-Nitroso compounds were known almost 40 years ago to be present in food treated with sodium nitrite, which made fish meal hepatotoxic to animals through formation of nitrosodimethylamine (NDMA). Since that time, N-nitroso compounds have been shown in animal experiments to be the most broadly acting and the most potent group of carcinogens. The key role of nitrite and nitrogen oxides in forming N-nitroso compounds by interaction with secondary and tertiary amino compounds has led to the examination worldwide of foods for the presence of N-nitroso compounds, which have been found almost exclusively in those foods containing nitrite or which have become exposed to nitrogen oxides. Among these are cured meats, especially bacon-and especially when cooked; concentrations of 100 micrograms kg(-1) have been found or, more usually, near 10 micrograms kg(-1). This would correspond to consumption of 1 microgram of NDMA in a 100-g portion. Much higher concentrations of NDMA (but lower ones of other nitrosamines) have been found in Japanese smoked and cured fish (more than 100 micrograms kg(-1)). Beer is one source of NDMA, in which as much as 70 micrograms l(-1) has been reported in some types of German beer, although usual levels are much lower (10 or 5 micrograms l(-1)); this could mean a considerable intake for a heavy beer drinker of several liters per day. Levels of nitrosamines have been declining during the past three decades, concurrent with a lowering of the nitrite used in food and greater control of exposure of malt to nitrogen oxides in beer making. There have been declines of N-nitroso compound concentrations in many foods during the past two decades. The small amounts of nitrosamines in food are nonetheless significant because of the possibility-even likelihood-that humans are more sensitive to these carcinogens than are laboratory rodents. Although it is probable that alkylnitrosamides (which induce brain tumors in rodents) are present in cured meats and other potentially nitrosated products in spite of much searching, there has been only limited indirect evidence of their presence. Copyright 1999 Elsevier Science B.V.

Exploration of biomarkers for total fish intake in pregnant Norwegian women.

OBJECTIVE: Few biomarkers for dietary intake of various food groups have been established. The aim of the present study was to explore whether selenium (Se), iodine, mercury (Hg) or arsenic may serve as a biomarker for total fish and seafood intake in addition to the traditionally used n-3 fatty acids EPA and DHA. DESIGN: Intake of fish and seafood estimated by an FFQ was compared with intake assessed by a 4 d weighed food diary and with biomarkers in blood and urine. SETTING: Validation study in the Norwegian Mother and Child Cohort Study (MoBa). SUBJECTS: One hundred and nineteen women. RESULTS: Total fish/seafood intake (median 39 g/d) calculated with the MoBa FFQ was comparable to intake calculated by the food diary (median 30 g/d, rS = 0.37, P < 0.001). Erythrocyte DHA and blood Hg, Se and arsenic concentrations were positively correlated with intake of fish and seafood, but the association for DHA was weakened by the widespread use of supplements. The main finding was the consistent positive association between the intake of fish/seafood and blood arsenic concentration. In multivariate analyses, blood arsenic was associated with blood Hg and fish and seafood intake. In these models, arsenic turned out to be the best indicator of intake of fish and seafood, both totally and in subgroups of fish/seafood intake. CONCLUSIONS: While DHA reflected the intake of fatty fish and n-3 PUFA supplements, blood arsenic concentration also reflected the intake of lean fish and seafood. Blood arsenic appears to be a useful biomarker for total fish and seafood intake.

Low Vitamin D Status: Definition, Prevalence, Consequences and Correction

Vitamin D is obtained from cutaneous production when 7-dehydrocholesterol is converted to vitamin D3 (cholecalciferol) by ultraviolet B radiation or by oral intake of vitamin D2 (ergocalciferol) and D3. An individual's vitamin D status is best evaluated by measuring the circulating 25-hydroxyvitamin D [25(OH)D] concentration. Though controversy surrounds the definition of low vitamin D status, there is increasing agreement that the optimal circulating 25(OH)D level should be ~30-32 ng/ml or above. Using this definition, it has been is estimated that approximately three quarters of all adults in the United States are low. Classically, low vitamin D status has skeletal consequences such as osteomalacia/rickets. More recently, associations between low vitamin D status and increased risk for various non-skeletal morbidities have been recognized; whether all of these associations are causally related to low vitamin D status remains to be determined. To achieve optimal vitamin D status, daily intakes of at least 1000 IU or more of vitamin D are required. The risk of toxicity with “high” amounts of vitamin D intake is low. Substantial between-individual variability exists in response to the same administered vitamin D dose. When to monitor 25(OH)D levels has received little attention. Supplementation with vitamin D3 may be preferable to vitamin D2.

Short- and long-term morbidity and mortality in the population exposed to dioxin after the "Seveso accident".

The early effects of 2,3,7,8-tetrachlorodibenzo-para-dioxin (TCDD) exposure in the population involved in the Seveso, Italy, incident in 1976, have been examined in numerous studies. Chloracne was the only effect linked with sufficient certainty to dioxin exposure. The possible long-term consequences were investigated with mortality and cancer incidence studies. Mortality and morbidity findings during the 20-year period following the accident showed increased risk from lymphoemopoietic neoplasm, digestive system cancer (rectum in males, and biliary tract among females, in particular) and respiratory system cancer (lung, among males). In the incidence analyses, also thyroid gland and pleura cancer appeared suggestively increased. Soft tissue sarcomas showed an increase in the largest, yet least exposed, exposure sub-cohort. Several hypotheses associating non-cancer effects with dioxin exposure were corroborated by findings in the Seveso population: this was the case with cardiovascular effects (possibly linked to both chemical exposure and stressful disaster experience), endocrine effects (diabetes among females) and reproductive effects: exposure of men to TCDD was linked to a lowered male/female sex ratio in their offspring. The results of many Seveso studies point to possible gender effects, in accordance with animal models. Notwithstanding the acknowledged study limitations (lack of individual exposure markers, short latency, and small population size for certain cancer types), results of previous experimental and epidemiological studies, along with mechanistic knowledge on dioxin toxicity, support the hypotheses that the observed excesses might be associated with dioxin exposure. The mortality and cancer incidence follow-up of the Seveso cohort are continuing.

Five years after To Err Is Human: what have we learned?

Five years ago, the Institute of Medicine (IOM) called for a national effort to make health care safe. Although progress since then has been slow, the IOM report truly "changed the conversation" to a focus on changing systems, stimulated a broad array of stakeholders to engage in patient safety, and motivated hospitals to adopt new safe practices. The pace of change is likely to accelerate, particularly in implementation of electronic health records, diffusion of safe practices, team training, and full disclosure to patients following injury. If directed toward hospitals that actually achieve high levels of safety, pay for performance could provide additional incentives. But improvement of the magnitude envisioned by the IOM requires a national commitment to strict, ambitious, quantitative, and well-tracked national goals. The Agency for Healthcare Research and Quality should bring together all stakeholders, including payers, to agree on a set of explicit and ambitious goals for patient safety to be reached by 2010.

A systematic review and meta-analysis of the effects of pasteurization on milk vitamins, and evidence for raw milk consumption and other health-rel...

Pasteurization of milk ensures safety for human consumption by reducing the number of viable pathogenic bacteria. Although the public health benefits of pasteurization are well established, pro-raw milk advocate organizations continue to promote raw milk as "nature's perfect food." Advocacy groups' claims include statements that pasteurization destroys important vitamins and that raw milk consumption can prevent and treat allergies, cancer, and lactose intolerance. A systematic review and meta-analysis was completed to summarize available evidence for these selected claims. Forty studies assessing the effects of pasteurization on vitamin levels were found. Qualitatively, vitamins B12 and E decreased following pasteurization, and vitamin A increased. Random effects meta-analysis revealed no significant effect of pasteurization on vitamin B6 concentrations (standardized mean difference [SMD], -2.66; 95% confidence interval [CI], -5.40, 0.8; P = 0.06) but a decrease in concentrations of vitamins B1 (SMD, -1.77; 95% CI, -2.57, -0.96; P < 0.001), B2 (SMD, -0.41; 95% CI, -0.81, -0.01; P < 0.05), C (SMD, -2.13; 95% CI, -3.52, -0.74; P < 0.01), and folate (SMD, -11.99; 95% CI, -20.95, -3.03; P < 0.01). The effect of pasteurization on milk's nutritive value was minimal because many of these vitamins are naturally found in relatively low levels. However, milk is an important dietary source of vitamin B2, and the impact of heat treatment should be further considered. Raw milk consumption may have a protective association with allergy development (six studies), although this relationship may be potentially confounded by other farming-related factors. Raw milk consumption was not associated with cancer (two studies) or lactose intolerance (one study). Overall, these findings should be interpreted with caution given the poor quality of reported methodology in many of the included studies.

Awareness and knowledge of methylmercury in fish in the United States.

In the 1970s several states in the Great Lakes region became concerned about mercury contamination in lakes and rivers and were the first to issue local fish consumption advisories. In 2001, the Food and Drug Administration (FDA) advised pregnant women, nursing mothers, young children, and women who may become pregnant not to consume shark, swordfish, king mackerel, and tilefish and recommended that these women not exceed 12 ounces of other fish per week. In 2004, FDA reissued this advice jointly with the U.S. Environmental Protection Agency (EPA) and modified it slightly to provide information about consumption of canned tuna and more details about consumption of recreationally caught fish. Though several studies have examined consumers' awareness of the joint FDA and EPA advisory as well as different state advisories, few used representative data. We examined the changes in awareness and knowledge of mercury as a problem in fish using the pooled nationally representative 2001 and 2006 Food Safety Surveys (FSS) with sample sizes of 4482 in 2001 and 2275 in 2006. Our results indicated an increase in consumers' awareness of mercury as a problem in fish (69% in 2001 to 80% in 2006, p<.001). In our regression models, we found that in both years, parents having children less than 5 years of age were more aware of mercury in fish and knowledgeable about the information contained in the national advisories about mercury in fish (p<.01) than other adults. In both 2001 and 2006, women of childbearing age (aged 18-45) were less aware and knowledgeable about this information than other women. However, women of all age groups had larger gains in awareness and knowledge than their male counterparts during this time. Participants' race, education, income, region, fish preparation experiences, having a foodborne illness in the past year, and risk perceptions about the safety of food were significant predictors of their awareness and knowledge. Copyright © 2011 Elsevier Inc. All rights reserved.

Association between isolation of Staphylococcus aureus one week after calving and milk yield, somatic cell count, clinical mastitis, and culling th...

Cows with isolation of Staphylococcus aureus approximately 1 week after calving and milk yield, somatic cell count (SCC), clinical mastitis (CM), and culling risk through the remaining lactation were assessed in 178 Norwegian dairy herds. Mixed models with repeated measures were used to compare milk yield and SCC, and survival analyses were used to estimate the hazard ratio for CM and culling. On average, cows with an isolate of Staph. aureus had a significantly higher SCC than culture-negative cows. If no post-milking teat disinfection (PMTD) was used, the mean values of SCC were 42,000, 61,000, 68,000 and 77,000 cells/ml for cows with no Staph. aureus isolate, with Staph. aureus isolated in 1 quarter, in 2 quarters and more than 2 quarters respectively. If iodine PMTD was used, SCC means were 36,000; 63,000; 70,000 and 122,000, respectively. Primiparous cows testing positive for Staph. aureus had the same milk yield curve as culture-negative cows, except for those with Staph. aureus isolated in more than 2 quarters. They produced 229 kg less during a 305-d lactation. Multiparous cows with isolation of Staph. aureus in at least 1 quarter produced 94-161 kg less milk in 2nd and >3rd parity, respectively, and those with isolation in more than 2 quarters produced 303-390 kg less than multiparous culture-negative animals during a 305-d lactation. Compared with culture-negative cows, the hazard ratio for CM and culling in cows with isolation of Staph. aureus in at least 1 quarter was 2.0 (1.6-2.4) and 1.7 (1.5-1.9), respectively. There was a decrease in the SCC and in the CM risk in culture-negative cows where iodine PMTD had been used, indicating that iodine PMTD has a preventive effect on already healthy cows. For cows testing positive for Staph. aureus in more than 2 quarters at calving, iodine PMTD had a negative effect on the CM risk and on the SCC through the remaining lactation.

A wholly nutritional 'multifocal angiostatic therapy' for control of disseminated cancer.

A great deal of effort is now being devoted to the development of new drugs that hopefully will control the spread of inoperable cancer by safely inhibiting tumor-evoked angiogenesis. However, there is growing evidence that certain practical nutritional measures have the potential to slow tumor angiogenesis, and it is reasonable to anticipate that, by combining several measures that work in distinct but complementary ways to impede the angiogenic process, a clinically useful 'multifocal angiostatic therapy' (MAT) might be devised. Several measures which might reasonably be included in such a protocol are discussed below, and include: a low-fat, low-glycemic index vegan diet, which may down-regulate the systemic IGF-I activity that supports angiogenesis; supplemental omega-3-rich fish oil, which has been shown to inhibit endothelial expression of Flk-1, a functionally crucial receptor for VEGF, and also can suppress tumor production of pro-angiogenic eicosanoids; high-dose selenium, which has recently been shown to inhibit tumor production of VEGF; green tea polyphenols, which can suppress endothelial responsiveness to both VEGF and fibroblast growth factor; and high-dose glycine, whose recently reported angiostatic activity may reflect inhibition of endothelial cell mitosis, possibly mediated by activation of glycine-gated chloride channels. In light of evidence that tumor-evoked angiogenesis has a high requirement for copper, copper depletion may have exceptional potential as an angiostatic measure, and is most efficiently achieved with the copper-chelating drug tetrathiomolybdate. If logistical difficulties make it difficult to acquire this experimental drug, high-dose zinc supplementation can achieve a slower depletion of the body's copper pool, and in any case can be used as maintenance therapy to maintain an adequate level of copper depletion. A provisional protocol is offered for a nutritionally based MAT entailing a vegan diet and supplemental intakes of fish oil, selenium, green tea polyphenols, glycine, and zinc. Inasmuch as cox-2 is overexpressed in many cancers, and cAMP can boost tumor production of various angiogenic factors as well as autogenous growth factors, adjunctive use of cox-2-specific NSAIDS may be warranted in some cases.

Radioactive fallout in the United States due to the Fukushima nuclear plant accident.

The release of radioactivity into the atmosphere from the damaged Fukushima Daiichi nuclear power plant started on March 12th, 2011. Among the various radionuclides released, iodine -131 ((131)I) and cesium isotopes ((137)Cs and (134)Cs) were transported across the Pacific Ocean and reached the United States on 17-18 March 2011. Consequently, an elevated level of fission products (131)I, (132)I, (132)Te, (134)Cs and (137)Cs were detected in air, water, and milk samples collected across the United States between March 17 and April 4, 2011. The continuous monitoring of activities over a period of 25 days and spatial variations across more than 100 sampling locations in the United States made it possible to characterize the contaminated air masses. For the entire period, the highest detected activity values ranged from less than 1 m Bq m(-3) to 31 m Bq m(-3) for the particulate (131)I, and up to 96 m Bq m(-3) for the gaseous (131)I fraction.

Major Pesticides Are More Toxic to Human Cells Than Their Declared Active Principles

Pesticides are used throughout the world as mixtures called formulations. They contain adjuvants, which are often kept confidential and are called inerts by the manufacturing companies, plus a declared active principle, which is usually tested alone. We tested the toxicity of 9 pesticides, comparing active principles and their formulations, on three human cell lines (HepG2, HEK293, and JEG3). Glyphosate, isoproturon, fluroxypyr, pirimicarb, imidacloprid, acetamiprid, tebuconazole, epoxiconazole, and prochloraz constitute, respectively, the active principles of 3 major herbicides, 3 insecticides, and 3 fungicides. We measured mitochondrial activities, membrane degradations, and caspases 3/7 activities. Fungicides were the most toxic from concentrations 300–600 times lower than agricultural dilutions, followed by herbicides and then insecticides, with very similar profiles in all cell types. Despite its relatively benign reputation, Roundup was among the most toxic herbicides and insecticides tested. Most importantly, 8 formulations out of 9 were up to one thousand times more toxic than their active principles. Our results challenge the relevance of the acceptable daily intake for pesticides because this norm is calculated from the toxicity of the active principle alone. Chronic tests on pesticides may not reflect relevant environmental exposures if only one ingredient of these mixtures is tested alone.

Dietary sources of inorganic microparticles and their intake in healthy subjects and patients with Crohn's disease.

Dietary microparticles are non-biological, bacterial-sized particles. Endogenous sources are derived from intestinal Ca and phosphate secretion. Exogenous sources are mainly titanium dioxide (TiO2) and mixed silicates (Psil); they are resistant to degradation and accumulate in human Peyer's patch macrophages and there is some evidence that they exacerbate inflammation in Crohn's disease (CD). However, whether their intake differs between those with and without CD has not been studied. We aimed to identify dietary microparticle sources and intakes in subjects with and without CD. Patients with inactive CD and matched general practice-based controls (ninety-one per group) completed 7 d food diaries. Intake data for dietary fibre and sucrose were compared as positive controls. All foods, pharmaceuticals and toothpastes were examined for microparticle content, and intakes of Ca and exogenous microparticles were compared between the two groups. Dietary intakes were significantly different between cases and controls for dietary fibre (12 (SD 5) v. 14 (SD 5) g/d; P=0.001) and sucrose (52 (SD 27) v. 45 (SD 18) g/d; P=0.04) but not for Ca. Estimated median TiO2 and Psil intakes (2.5 and 35 mg/individual per d respectively, totalling 10(12)-10(13) microparticles/individual per d) were broadly similar to per capita estimates and while there was wide variation in intakes between individuals there was no significant difference between subjects with CD and controls. Hence, if exposure to microparticles is associated with the inflammation of CD, then the present study rules out excess intake as the problem. Nonetheless, microparticle-containing foods have now been identified which allows a low-microparticle diet to be further assessed in CD.

Biomonitoring of urinary metabolites of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) following human consumption of cooked chicken.

Human risk assessment of exposure to 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) through the diet may be improved by conducting biomonitoring studies comparing metabolism in humans and rodents. Eleven volunteers ingested a meal of cooked chicken containing 4 -OH-PhIP and PhIP in amounts of 0.6 and 0.8microg/kg, respectively and urine was collected for the next 16h. The large number of PhIP metabolites was by treatment of the urine samples with hydrazine hydrate and hydrolytic enzymes reduced to three substances, 4'-OH-PhIP, PhIP and 5-OH-PhIP of which the first is a biomarker for detoxification and the last a biomarker for activation. The eleven volunteers eliminated large amounts of 4'-OH-PhIP in the urine. The majority of which could be accounted for by the presence of 4'-OH-PhIP in the fried chicken, showing that PhIP only to a small extent (11%) was metabolised to 4'-OH-PhIP. A larger fraction of the PhIP exposure, 38%, was recovered as PhIP and the largest fraction (51%) was recovered as 5-OH-PhIP suggesting that PhIP in humans to a large extent is metabolised to reactive substances. In rats, less than 1% of the dose of PhIP was eliminated as 5-OH-PhIP, suggesting that human cancer risk from exposure to PhIP is considerable higher than risk estimations based on extrapolation from rodent bioassays.

Genistein genotoxicity: critical considerations of in vitro exposure dose.

The potential health benefits of soy-derived phytoestrogens include their reported utility as anticarcinogens, cardioprotectants and as hormone replacement alternatives in menopause. Although there is increasing popularity of dietary phytoestrogen supplementation and of vegetarian and vegan diets among adolescents and adults, concerns about potential detrimental or other genotoxic effects persist. While a variety of genotoxic effects of phytoestrogens have been reported in vitro, the concentrations at which such effects occurred were often much higher than the physiologically relevant doses achievable by dietary or pharmacologic intake of soy foods or supplements. This review focuses on in vitro studies of the most abundant soy phytoestrogen, genistein, critically examining dose as a crucial determinant of cellular effects. In consideration of levels of dietary genistein uptake and bioavailability we have defined in vitro concentrations of genistein >5 microM as non-physiological, and thus "high" doses, in contrast to much of the previous literature. In doing so, many of the often-cited genotoxic effects of genistein, including apoptosis, cell growth inhibition, topoisomerase inhibition and others become less obvious. Recent cellular, epigenetic and microarray studies are beginning to decipher genistein effects that occur at dietarily relevant low concentrations. In toxicology, the well accepted principle of "the dose defines the poison" applies to many toxicants and can be invoked, as herein, to distinguish genotoxic versus potentially beneficial in vitro effects of natural dietary products such as genistein.

Diallyl sulfide inhibits PhIP-induced DNA strand breaks in normal human breast epithelial cells.

Heterocyclic amines (HCAs) are formed when meat products such as beef, chicken, pork and fish are cooked at high temperatures. The most abundant HCA found in the human diet is 2-amino-1-methyl-6-phenylimidazo[4,5-b] pyridine (PhIP). PhIP causes mammary carcinomas in female rats and mice, and is associated with an increased risk of developing colon, breast, and prostate cancer in humans. PhIP is metabolized by cytochrome P-450s producing N-OH-PhIP. The N-OH-PhIP can be esterified by phase II enzymes forming an arylnitrenium ion that binds to DNA causing adducts. Furthermore, N-OH-PhIP may be reduced by cytochrome b5 reductase producing superoxide anions and hydroxyl radicals causing DNA strand breaks. Diallyl sulfide (DAS) has been shown to prevent cancer in several animal models, presumably by metabolic modulation. We hypothesize that PhIP produces reactive oxygen species causing DNA strand breaks and that DAS will inhibit the formation of PhIP induced DNA strand breaks. To test this hypothesis we treated normal breast epithelial (MCF-10A) cells with PhIP, DAS and a combination of PhIP and DAS. The detection of lipid peroxides was used as a surrogate for ROS. Lipid peroxides were detected using a PeroxiDetect kit (Sigma). PhIP increased the production of lipid peroxides and DAS decreased the PhIP-induced peroxidation by 47%. To determine if PhIP causes DNA strand breaks in MCF-10A cells, cells were treated for 3, 6, 9, and 24 h with PhIP (100 microM), DAS (100 microM) and a combination of PhIP (100 microM) and DAS (100 microM). DNA strand breaks were evaluated using the Comet assay. PhIP produced DNA strand breaks in a dose- and time-dependent fashion. We have shown that DAS inhibits PhIP-induced DNA strand breaks by inhibiting the production of reactive oxygen species. Therefore, we propose that DAS can prevent PhIP-induced breast cancer.

Genotoxicity of lavender oil, linalyl acetate, and linalool on human lymphocytes in vitro.

The potential genotoxicity of lavender essential oil and its major components, linalool, and linalyl acetate, was evaluated in vitro by the micronucleus test on peripheral human lymphocytes. In the range of non-toxic concentrations (0.5-100 μg/ml), linalyl acetate increased the frequency of micronuclei significantly and in concentration-dependent manner; lavender oil did so only at the highest concentration tested, whereas linalool was devoid of genotoxicity. None of the tested substances led to an increase in nucleoplasmic bridges or nuclear buds frequency. These findings suggest that the mutagenic activity of lavender oil can be related to the presence of linalyl acetate, which seems to have a profile of an aneugenic agent. Copyright © 2010 Wiley-Liss, Inc.

Antioxidant capacity and other bioactivities of the freeze-dried Amazonian palm berry, Euterpe oleraceae mart. (acai).

The fruit of Euterpe oleraceae, commonly known as acai, has been demonstrated to exhibit significantly high antioxidant capacity in vitro, especially for superoxide and peroxyl scavenging, and, therefore, may have possible health benefits. In this study, the antioxidant capacities of freeze-dried acai fruit pulp/skin powder (OptiAcai) were evaluated by different assays with various free radical sources. It was found to have exceptional activity against superoxide in the superoxide scavenging (SOD) assay, the highest of any food reported to date against the peroxyl radical as measured by the oxygen radical absorbance capacity assay with fluorescein as the fluorescent probe (ORACFL), and mild activity against both the peroxynitrite and hydroxyl radical by the peroxynitrite averting capacity (NORAC) and hydroxyl radical averting capacity (HORAC) assays, respectively. The SOD of acai was 1614 units/g, an extremely high scavenging capacity for O2*-, by far the highest of any fruit or vegetable tested to date. Total phenolics were also tested as comparison. In the total antioxidant (TAO) assay, antioxidants in acai were differentiated into "slow-acting" and "fast-acting" components. An assay measuring inhibition of reactive oxygen species (ROS) formation in freshly purified human neutrophils showed that antioxidants in acai are able to enter human cells in a fully functional form and to perform an oxygen quenching function at very low doses. Furthermore, other bioactivities related to anti-inflammation and immune functions were also investigated. Acai was found to be a potential cyclooxygenase (COX)-1 and COX-2 inhibitor. It also showed a weak effect on lipopolysaccharide (LPS)-induced nitric oxide but no effect on either lymphocyte proliferation and phagocytic capacity.

Too early to dismiss Yersinia enterocolitica infection in the aetiology of Graves' disease: evidence from a twin case-control study.

BACKGROUND: Yersinia enterocolitica (YE) infection has long been implicated in the pathogenesis of Graves' disease (GD). The association between YE and GD could, however, also be due to common genetic or environmental factors affecting the development of both YE infection and GD. This potential confounding can be minimized by investigation of twin pairs discordant for GD. AIM: To examine whether YE infection is associated with GD. DESIGN: We first conducted a classical case-control study of individuals with (61) and without (122) GD, and then a case-control study of twin pairs (36) discordant for GD. METHODS: Immunoglobulin (Ig)A and IgG antibodies to virulence-associated Yersinia outer membrane proteins (YOPs) were measured. MAIN OUTCOME MEASURES: The prevalence of YOP IgA and IgG antibodies. RESULTS: Subjects with GD had a higher prevalence of YOP IgA (49%vs. 34%, P = 0.054) and YPO IgG (51%vs. 35%, P = 0.043) than the external controls. The frequency of chronic YE infection, reflected by the presence of both IgA and IgG YOP antibodies, was also higher among cases than controls (49%vs. 33%, P = 0.042). Similar results were found in twin pairs discordant for GD. In the case-control analysis, individuals with GD had an increased odds ratio (OR) of YE infection: IgA 1.84 (95% CI 0.99-3.45) and IgG 1.90 (95% CI 1.02-3.55). In the co-twin analysis, the twin with GD also had an increased OR of YE infection: IgA 5.5 (95% CI 1.21-24.81) and IgG 5.0 (95% CI 1.10-22.81). CONCLUSION: The finding of an association between GD and YE in the case-control study and within twin pairs discordant for GD supports the notion that YE infection plays an aetiological role in the occurrence of GD, or vice versa. Future studies should examine the temporal relationship of this association in more depth.

Effects of sorbic acid and its salts on chromosome aberrations, sister chromatid exchanges and gene mutations in cultured Chinese hamster cells.

The ability of sorbic acid and its potassium and sodium salts to induce chromosome aberrations, sister chromatid exchanges (SCE) and gene mutations in cultured Chinese hamster V79 cells was examined. Sodium sorbate caused significant induction of chromosome aberrations and SCE, and also induced 6-thioguanine-resistant mutations in a dose-dependent manner. The clastogenic potency of sodium sorbate was found to be less than one hundredth of that of the potent clastogen N-methyl-N'-nitro-N-nitrosoguanidine. The induction of SCE by sodium sorbate was twice the control level, whereas that by methyl methanesulphonate, a potent inducer of SCE, was 14 times the control level. The mutagenic potency of sodium sorbate was less than one-tenth that of ethyl methanesulphonate, a potent inducer of mutation, when compared at an equitoxic level. Sorbic acid and its potassium salt induced chromosome aberrations, but only at the highest doses tested. These compounds also induced 1.2 times the control level of SCE, but neither compound induced 6-thioguanine-resistant mutations. The cytogenetic activity of sodium sorbate was concluded not to be due to the effect of osmotic pressure or an impurity. These results indicate that sodium sorbate is a genotoxic agent, although its potency seems to be weak, and that sorbic acid and potassium sorbate are less genotoxic than the sodium salt.

A modest proposal for a longitudinal study of dementia prevention (with apologies to Jonathan Swift, 1729).

Many studies have documented the role of risk and protective factors for late life dementing illnesses, particularly Alzheimer's disease. A "Systematic Review" from the US Agency for Healthcare Research and Quality and the National Institute on Aging concluded that because the overall quality of evidence was low, recommendations for public health could not be made. In order to gain evidence for the efficacy of lifestyle interventions, we propose a "Modest Proposal" to study 10,000 subjects over 40 years randomly assigned to groups of low or high saturated fat in the diet, head injury, and high or low levels of mental activity, physical activity, or inactivity as well as smoking or non-smoking. This proposed study cannot be accomplished. The "Modest Proposal" illustrates that the absence of definitive evidence should not restrict physicians from making reasonable recommendations based on the evidence that is available.

Cigarette smoke radioactivity and lung cancer risk.

INTRODUCTION: To determine the tobacco industry's policy and action with respect to radioactive polonium 210 ((210)Po) in cigarette smoke and to assess the long-term risk of lung cancer caused by alpha particle deposits in the lungs of regular smokers. METHODS: Analysis of major tobacco industries' internal secret documents on cigarette radioactivity made available online by the Master Settlement Agreement in 1998. RESULTS: The documents show that the industry was well aware of the presence of a radioactive substance in tobacco as early as 1959. Furthermore, the industry was not only cognizant of the potential "cancerous growth" in the lungs of regular smokers but also did quantitative radiobiological calculations to estimate the long-term (25 years) lung radiation absorption dose (rad) of ionizing alpha particles emitted from the cigarette smoke. Our own calculations of lung rad of alpha particles match closely the rad estimated by the industry. According to the Environmental Protection Agency, the industry's and our estimate of long-term lung rad of alpha particles causes 120-138 lung cancer deaths per year per 1,000 regular smokers. Acid wash was discovered in 1980 to be highly effectively in removing (210)Po from the tobacco leaves; however, the industry avoided its use for concerns that acid media would ionize nicotine converting it into a poorly absorbable form into the brain of smokers thus depriving them of the much sought after instant "nicotine kick" sensation. CONCLUSIONS: The evidence of lung cancer risk caused by cigarette smoke radioactivity is compelling enough to warrant its removal.

Milk Intake and Total Dairy Consumption: Associations with Early Menarche in NHANES 1999-2004

Background Several components of dairy products have been linked to earlier menarche. Methods/Findings This study assessed whether positive associations exist between childhood milk consumption and age at menarche or the likelihood of early menarche (<12 yrs) in a U.S sample. Data derive from the National Health and Nutrition Examination Survey (NHANES) 1999–2004. Two samples were utilized: 2657 women age 20–49 yrs and 1008 girls age 9–12 yrs. In regression analysis, a weak negative relationship was found between frequency of milk consumption at 5–12 yrs and age at menarche (daily milk intake β = −0.32, P<0.10; “sometimes/variable milk intake” β = −0.38, P<0.06, each compared to intake rarely/never). Cox regression yielded no greater risk of early menarche among those who drank milk “sometimes/varied” or daily vs. never/rarely (HR: 1.20, P<0.42, HR: 1.25, P<0.23, respectively). Among the 9–12 yr olds, Cox regression indicated that neither total dairy kcal, calcium and protein, nor daily milk intake in the past 30 days contributed to early menarche. Girls in the middle tertile of milk intake had a marginally lower risk of early menarche than those in the highest tertile (HR: 0.6, P<0.06). Those in the lowest tertiles of dairy fat intake had a greater risk of early menarche than those in the highest (HR: 1.5, P<0.05, HR: 1.6, P<0.07, lowest and middle tertile, respectively), while those with the lowest calcium intake had a lower risk of early menarche (HR: 0.6, P<0.05) than those in the highest tertile. These relationships remained after adjusting for overweight or overweight and height percentile; both increased the risk of earlier menarche. Blacks were more likely than Whites to reach menarche early (HR: 1.7, P<0.03), but not after controlling for overweight. Conclusions There is some evidence that greater milk intake is associated with an increased risk of early menarche, or a lower age at menarche.

gamma-Irradiation dose: effects on baby-leaf spinach ascorbic acid, carotenoids, folate, alpha-tocopherol, and phylloquinone concentrations.

Ionizing radiation of fruits and vegetables, in the form of gamma rays or electron beams, is effective in overcoming quarantine barriers in trade and prolonging shelf life, but a void of information persists on ionizing radiation effects of vitamin profiles in individual foods. Baby-leaf spinach from commercial cultivars, flat-leafed 'Lazio' and crinkled-leaf 'Samish', was grown, harvested, and surface sanitized according to industry practices. Baby-leaf spinach of each cultivar was packaged under air or N(2) atmosphere, representing industry practices, then exposed to cesium-137 gamma-radiation at 0.0, 0.5, 1.0, 1.5, or 2.0 kGy. Following irradiation, leaf tissues were assayed for vitamin (C, E, K, B(9)) and carotenoid (lutein/zeaxanthin, neoxanthin, violoxanthin, and beta-carotene) concentrations. Atmospheres by irradiation had little consistent effect, but N(2) versus air was associated with elevated dihydroascorbic acid levels. Four phytonutrients (vitamins B(9), E, and K and neoxanthin) exhibited little or no change in concentration with increasing doses of irradiation. However, total ascorbic acid (vitamin C), free ascorbic acid, lutein/zeaxanthin, violaxanthin, and beta-carotene all were significantly reduced at 2.0 kGy and, depending on cultivar, were affected at lesser doses of 0.5 and 1.5 kGy. Dihydroascorbic acid, the most affected compound and an indicator of stress, likely due to irradiation-generated oxidative radicals, increased with increasing irradiation doses >0.5 kGy.

The significance of azo-reduction in the mutagenesis and carcinogenesis of azo dyes.

Azo dyes are widely used in textile, printing, cosmetic, drug and food-processing industries. They are also used extensively in laboratories as either biological stains or pH indicators. The extent of such use is related to the degree of industrialization. Since intestinal cancer is more common in highly industrialized countries, a possible connection may exist between the increase in the number of cancer cases and the use of azo dyes. Azo dyes can be reduced to aromatic amines by the intestinal microflora. The mutagenicity of a number of azo dyes is reviewed in this paper. They include Trypan Blue, Ponceau 3R, Pinceau 2R, Methyl Red, Methyl Yellow, Methyl Orange, Lithol Red, Orange I, Orange II, 4-Phenylazo-Naphthylamine, Sudan I, Sudan IV, Acid Alizarin Violet N, Fast Garnet GBC, Allura Red, Ponceau SX, Sunset Yellow, Tartrazine, Citrus Red No. 2, Orange B, Yellow AB, Carmoisine, Mercury Orange, Ponceau S, Versatint Blue, Phenylazophenol, Evan's Blue and their degraded aromatic amines. The significance of azo reduction in the mutagenesis and carcinogenesis of azo dyes is discussed.

Gastro-intestinal availability of aluminium from tea.

The in vitro speciation of aluminium (Al) in black tea infusion (pH 4.8) was assessed using 3000, 10,000 and 30,000 Da cut-off ultrafilters, and the effect of adding human gastric juice (pH 2.3) and then raising the pH to 6.5 were also studied. 78% Al in the tea infusion passed through the 3000-Da ultrafilter; this percentage increased to more than 90% with the addition of gastric juice at pH 2.3, but then reduced to approximately 5% when the incubate was adjusted to pH 6.5. The breakdown of tea-derived polyphenols to low molecular weight phenols in vivo was measured using high-resolution 1H nuclear magnetic resonance spectroscopic analysis of ileostomy effluent, but there was no evidence of low molecular weight breakdown products from the polyphenols of ingested tea in this effluent. These results suggest that only a small proportion of Al in tea is potentially available for absorption throughout the small bowel. It may be misleading to estimate systemic Al absorption from tea drinking simply from total urinary aluminium excretion as has been done previously.

Children as guinea pigs: historical perspective.

Experimentation involving children is not a new phenomenon. Children have been used as research subjects in a diverse set of experiments, including the trials of new vaccines and sera, in efforts to understand normal pediatric anatomy and physiology and in the development of new drugs and procedures. Concern about child participants in research is also not a new development. For more than a century, critics of medical research have called attention to the fact that children and other vulnerable populations--pregnant women, prisoners, the mentally ill--have too often served as the unwitting and unwilling subjects of medical experiments. This paper looks at several early cases in which children participated, including the first trial of cowpox vaccine, the first human trial of rabies vaccine, and the first treatment of Listerian wound antisepsis. The history of concern for children, especially institutionalized children, in medical research is considered along with the development of regulations or guidelines, including the Declaration of Helsinki (1964).

Radioprotection by plant products: present status and future prospects.

The development of radioprotective agents has been the subject of intense research in view of their potential for use within a radiation environment, such as space exploration, radiotherapy and even nuclear war. However, no ideal, safe synthetic radioprotectors are available to date, so the search for alternative sources, including plants, has been on going for several decades. In Ayurveda, the traditional Indian system of medicine, several plants have been used to treat free radical-mediated ailments and, therefore, it is logical to expect that such plants may also render some protection against radiation damage. A systematic screening approach can provide leads to identifying potential new candidate drugs from plant sources, for mitigation of radiation injury. This article reviews some of the most promising plants, and their bioactive principles, that are widely used in traditional systems of medicine, and which have rendered significant radioprotection in both in vitro and in vivo model systems. Plants and their constituents with pharmacological activities that may be relevant to amelioration of radiation-mediated damage, including antiemetic, antiinflammatory, antioxidant, cell proliferative, wound healing and haemopoietic stimulatories are also discussed. Copyright (c) 2005 John Wiley & Sons, Ltd.

Neurotoxic effects of aluminium among foundry workers and Alzheimer's disease.

BACKGROUND: In a cross-sectional case-control study conducted in northern Italy, 64 former aluminium dust-exposed workers were compared with 32 unexposed controls from other companies matched for age, professional training, economic status, educational and clinical features. The findings lead the authors to suggest a possible role of the inhalation of aluminium dust in pre-clinical mild cognitive disorder which might prelude Alzheimer's disease (AD) or AD-like neurological deterioration. METHODS: The investigation involved a standardised occupational and medical history with particular attention to exposure and symptoms, assessments of neurotoxic metals in serum: aluminium (Al-s), copper (Cu-s) and zinc (Zn-s), and in blood: manganese (Mn-b), lead (Pb-b) and iron (Fe-b). Cognitive functions were assessed by the Mini Mental State Examination (MMSE), the Clock Drawing Test (CDT) and auditory evoked Event-Related Potential (ERP-P300). To detect early signs of mild cognitive impairment (MCI), the time required to solve the MMSE (MMSE-time) and CDT (CDT-time) was also measured. RESULTS: Significantly higher internal doses of Al-s and Fe-b were found in the ex-employees compared to the control group. The neuropsychological tests showed a significant difference in the latency of P300, MMSE score, MMSE-time, CDT score and CDT-time between the exposed and the control population. P300 latency was found to correlate positively with Al-s and MMSE-time. Al-s has significant effects on all tests: a negative relationship was observed between internal Al concentrations, MMSE score and CDT score; a positive relationship was found between internal Al concentrations, MMSE-time and CDT-time. All the potential confounders such as age, height, weight, blood pressure, schooling years, alcohol, coffee consumption and smoking habit were taken into account. CONCLUSIONS: These findings suggest a role of aluminium in early neurotoxic effects that can be detected at a pre-clinical stage by P300, MMSE, MMSE-time, CDT-time and CDT score, considering a 10 micrograms/l cut-off level of serum aluminium, in aluminium foundry workers with concomitant high blood levels of iron. The authors raise the question whether pre-clinical detection of aluminium neurotoxicity and consequent early treatment might help to prevent or retard the onset of AD or AD-like pathologies.

Human exposure to endocrine disrupters: carcinogenic risk assessment.

Human exposure to endocrine disrupters (EDs) is widespread and is considered to pose a growing threat to human health. Recent advances in molecular and genetic research and better understanding of mechanisms of blastic cell transformation have led to efforts to improve cancer risk assessment for populations exposed to this family of xenobiotics. In risk assessment, low dose extrapolation of cancer incidence data from both experimental animals and epidemiology studies has been largely based on models assuming linear correlation at low doses, despite existence of evidence showing otherwise. Another weakness of ED risk assessment is poor exposure data in ecological studies. Those are frequently rough estimates derived from contaminated items of local food basket surveys. Polyhalogenated hydrocarbons are treated as examples. There is growing sense of urgency to develop a biologically based dose response model of cancer risk, integrating emerging data from molecular biology and epidemiology to provide more realistic data for risk assessors, public, public health managers and environmental issues administrators.

Dietary factors and cancer mortality among atomic-bomb survivors.

Dietary factors such as fruit and vegetables are thought to reduce the risk of cancer incidence and mortality. We investigated the effect of a diet rich in fruit and vegetables against the long-term effects of radiation exposure on the risk of cancer. A cohort of 36,228 atomic-bomb survivors of Hiroshima and Nagasaki, for whom radiation dose estimates were currently available, had their diet assessed in 1980. They were followed for a period of 20 years for cancer mortality. The joint-effect of fruit and vegetables intake and radiation exposure on risk of cancer death was examined, in additive (sum of effects of diet alone and radiation alone) and multiplicative (product of effects of diet alone and radiation alone) models. In the additive model, a daily intake of fruit and vegetables significantly reduced the risk of cancer deaths by 13%, compared to an intake of once or less per week. Radiation exposure of 1 Sievert (Sv) increased significantly the risk of cancer death by 48-49%. The additive joint-effects showed a lower risk of cancer among those exposed to 1 Sv who had a diet rich in vegetables (49%-13%=36%) or fruit (48%-13%=35%). The multiplicative model gave similar results. The cancer risk reduction by vegetables in exposed persons went from 52% (effect of radiation alone) to 32% (product of effect of vegetables and radiation), and cancer risk reduction by fruit was 52% (radiation alone) to 34% (product of effect of fruit and radiation). There was no significant evidence to reject either the additive or the multiplicative model. A daily intake of fruit and vegetables was beneficial to the persons exposed to radiation in reducing their risks of cancer death.

The experience of Japan as a clue to the etiology of testicular and prostatic cancers.

In Japan dramatic lifestyle changes occurred after World War 2. To examine the experience of Japan as a clue to the etiology, trends in the mortality rates of testicular and prostatic cancers from 1947 to 1998 were related to changes in dietary practices. The male population born before 1945 had a peak in death from testicular cancer in their thirties or forties, whereas those born after 1946 had a peak in their twenties. The death rate of prostatic cancer increased 25-fold almost linearly after the war. The intake of milk, meat, and eggs increased 20-, 9-, and 7-fold, respectively, after the war. In connection with the development and growth of testicular and prostatic cancers in Japan, particular attention should be paid to milk, because the increase in its consumption in this country is a recent occurrence and because milk contains considerable amounts of estrogens plus saturated fats.

Effect of diet on serum albumin and hemoglobin adducts of 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) in humans.

2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) is the most abundant heterocyclic amine formed in meat and fish during cooking and can be used as a model compound for this class of chemicals possibly involved in human carcinogenesis. Knowing the exposure to heterocyclic amines is important for establishing their role in human diseases. Serum albumin (SA) and globin (Gb) adducts were first tested as biomarkers of exposure to PhIP in male Fischer 344 rats given oral doses of 0.1, 0.5, 1 and 10 mg/kg. Blood samples were collected 24 hr after treatment and PhIP released from SA and Gb after acidic hydrolysis was analyzed by gas chromatography-mass spectrometry or liquid chromatography-tandem mass spectrometry. PhIP-SA and Gb adducts increased linearly with the dose. Studies on 35 volunteers with different dietary habits exhibited that diet was a major determinant in the formation of both adducts. PhIP-SA adducts were significantly higher in meat consumers than in vegetarians (6.7 +/- 1.6 and 0.7 +/- 0.3 fmol/mg SA; respectively, mean +/- SE; p = 0.04, Mann-Whitney U test). The Gb adduct pattern was quantitatively lower but paralleled SA (3 +/- 0.8 in meat consumers and 0.3 +/- 0.1 in vegetarians). PhIP-SA adducts were no different in smokers and in non-smokers. The results show for the first time that PhIP-blood protein adducts are present in humans not given the synthetic compound. Both biomarkers appear to be suitable for assessing dietary exposure and internal PhIP dose and may be promising tools for studying the role of heterocyclic amines in the etiology of colon cancer and other diseases. Copyright 2000 Wiley-Liss, Inc.

Good riddance: Thymocyte clonal deletion prevents autoimmunity.

Clonal deletion is arguably the most important mechanism of eliminating self-reactive thymocytes from the T-cell repertoire. Recent work has identified new players in this process. On the thymocyte side, several molecules have been newly implicated in the pathway from initial T-cell receptor signaling through to the final result: gene transcription and thymocyte apoptosis. In addition, several proapoptotic molecules have been found to be necessary for the death of self-reactive thymocytes. On the antigen-presenting cell side, the expression of peripheral self-antigens, regulated at least in part by the autoimmune regulator (AIRE) protein, is crucial for complete elimination of autoreactive thymocytes. The importance of thymic peripheral antigen expression and clonal deletion to self-tolerance is demonstrated in the autoimmune diseases autoimmune-polyendocrinopathy-candidiasis-ectodermal dystrophy and type-1 diabetes mellitus.

Heavy metal content of ayurvedic herbal medicine products.

CONTEXT: Lead, mercury, and arsenic intoxication have been associated with the use of Ayurvedic herbal medicine product (HMPs). OBJECTIVES: To determine the prevalence and concentration of heavy metals in Ayurvedic HMPs manufactured in South Asia and sold in Boston-area stores and to compare estimated daily metal ingestion with regulatory standards. DESIGN AND SETTING: Systematic search strategy to identify all stores 20 miles or less from Boston City Hall that sold Ayurvedic HMPs from South Asia by searching online Yellow Pages using the categories markets, supermarkets, and convenience stores, and business names containing the word India, Indian cities, and Indian words. An online national directory of Indian grocery stores, a South Asian community business directory, and a newspaper were also searched. We visited each store and purchased all unique Ayurvedic HMPs between April 25 and October 24, 2003. MAIN OUTCOME MEASURES: Concentrations (microg/g) of lead, mercury, and arsenic in each HMP as measured by x-ray fluorescence spectroscopy. Estimates of daily metal ingestion for adults and children estimated using manufacturers' dosage recommendations with comparisons to US Pharmacopeia and US Environmental Protection Agency regulatory standards. RESULTS: A total of 14 (20%) of 70 HMPs (95% confidence interval, 11%-31%) contained heavy metals: lead (n = 13; median concentration, 40 microg/g; range, 5-37,000), mercury (n = 6; median concentration, 20,225 microg/g; range, 28-104,000), and/or arsenic (n = 6; median concentration, 430 microg/g; range, 37-8130). If taken as recommended by the manufacturers, each of these 14 could result in heavy metal intakes above published regulatory standards. CONCLUSIONS: One of 5 Ayurvedic HMPs produced in South Asia and available in Boston South Asian grocery stores contains potentially harmful levels of lead, mercury, and/or arsenic. Users of Ayurvedic medicine may be at risk for heavy metal toxicity, and testing of Ayurvedic HMPs for toxic heavy metals should be mandatory.

Hair mercury levels of women of reproductive age in Ontario, Canada: implications to fetal safety and fish consumption.

OBJECTIVE: To study hair mercury concentrations among women of reproductive age in relation to fish intake in Ontario, Canada. STUDY DESIGN: Three groups were studied: 22 women who had called the Motherisk Program for information on the reproductive safety of consuming fish during pregnancy, a group of Japanese residing in Toronto (n=23) consuming much larger amounts of fish, and a group of Canadian women of reproductive age (n=20) not seeking advice, were studied. Mercury concentrations in hair samples were measured using inductively coupled plasma mass spectrometry. Seafood consumption habits were recorded for each participant. Based on the types of fish consumed and consumption frequencies, the estimated monthly intake of mercury was calculated. Hair mercury concentrations were correlated to both the number of monthly seafood servings and the estimated ingested mercury dose. RESULTS: There were significant correlations between fish servings and hair mercury (Spearman r=0.73, P<.0001) and between amounts of consumed mercury and hair mercury concentrations (Spearman r=0.81, P<.0001). Nearly two thirds of the Motherisk callers, all of the Japanese women, and 15% of the Canadian women of reproductive age had hair mercury above 0.3 microg/g, which was shown recently to be the lowest observable adverse effect level in a large systematic review of all perinatal studies. CONCLUSIONS: Because of very wide variability, general recommendations for a safe number of fish servings may not be sufficient to protect the fetus. Analysis of hair mercury may be warranted before pregnancy in selected groups of women consuming more than 12 ounces of fish per week, as dietary modification can decrease body burden and ensure fetal safety. Copyright (c) 2010. Published by Mosby, Inc.

Marine Food Pollutants as a Risk Factor for Hypoinsulinemia and Type 2 Diabetes

Background Some persistent environmental chemicals are suspected of causing an increased risk of type 2 diabetes mellitus, a disease particularly common after age 70. This concern was examined in a cross-sectional study of elderly subjects in a population with elevated contaminant exposures from seafood species high in the food chain. Methods Clinical examinations of 713 Faroese residents aged 70-74 years (64% of eligible population) included fasting plasma concentrations of glucose and insulin, and glycosylated hemoglobin. Lifetime exposure to persistent environmental chemicals from pilot whale and other traditional food was estimated from a dietary questionnaire and by analysis of blood samples for polychlorinated biphenyls (PCBs) and related food contaminants. Results Septuagenarians with type 2 diabetes or impaired fasting glycemia tended to have higher PCB concentrations and higher past intake of traditional foods, especially during childhood and adolescence. In non-diabetic subjects, the fasting insulin concentration decreased by 7% (95% CI= −12% to −2%) for each doubling of the PCB concentration after adjustment for sex and body mass index at age 20. Conversely, the fasting glucose concentration increased by 6% (−1% to 13%) for each doubling in PCB. Similar associations were seen in subjects without impaired fasting glycemia, while further adjustment for current body mass index and lipid metabolism parameters attenuated some of the associations. Conclusions Impaired insulin secretion appears to constitute an important part of the type 2 diabetes pathogenesis associated with exposure to persistent lipophilic food contaminants.

Inorganic arsenic in rice bran and its products are an order of magnitude higher than in bulk grain.

Rice is more elevated in arsenic than all other grain crops tested to date, with whole grain (brown) rice having higher arsenic levels than polished (white). It is reported here that rice bran, both commercially purchased and specifically milled for this study, have levels of inorganic arsenic, a nonthreshold, class 1 carcinogen, reaching concentrations of approximately 1 mg/kg dry weight, around 10-20 fold higher than concentrations found in bulk grain. Although pure rice bran is used as a health food supplement, perhaps of more concern is rice bran solubles, which are marketed as a superfood and as a supplement to malnourished children in international aid programs. Five rice bran solubles products were tested, sourced from the United States and Japan, and were found to have 0.61-1.9 mg/kg inorganic arsenic. Manufactures recommend approximately 20 g servings of the rice bran solubles per day, which equates to a 0.012-0.038 mg intake of inorganic arsenic. There are no maximum concentration levels (MCLs) set for arsenic or its species in food stuffs. EU and U.S. water regulations, set at 0.01 mg/L total or inorganic arsenic, respectively, are based on the assumption that 1 L of water per day is consumed, i.e., 0.01 mg of arsenic/ day. At the manufacturers recommended rice bran solubles consumption rate, inorganic arsenic intake exceeds 0.01 mg/ day, remembering that rice bran solubles are targeted at malnourished children and that actual risk is based on mg kg(-1) day(-1) intake.

Monitoring of mercury, arsenic, and lead in traditional Asian herbal preparations on the Dutch market and estimation of associated risks.

Traditional herbal preparations used in Ayurveda, traditional Chinese medicine, traditional Tibetan medicine, and other Asian traditional medicine systems may contain significant amounts of mercury, arsenic or lead. Though deliberately incorporated in Asian traditional herbal preparations for therapeutic purposes, these constituents have caused intoxications worldwide. The aim of this study was therefore to determine mercury, arsenic, and lead levels in Asian traditional herbal preparations on the Dutch market. A total of 292 traditional herbal preparations used in Ayurveda, traditional Chinese medicine, and traditional Tibetan medicine were sampled between 2004 and 2007. Samples were mostly multi-ingredient traditional herbal preparations containing herbs and minerals. The labeling of less than 20% of the traditional herbal preparations suggested the presence of mercury, arsenic or lead. These elements were shown by inductively coupled mass spectrometry (ICP-MS) in 186 (64%) of 292 traditional herbal preparations. Estimated weekly mercury, arsenic, and lead intake levels were calculated for each traditional herbal preparation from the analytically determined concentrations and the recommended dose. A total of 59 traditional herbal preparations (20%) were likely to result in intakes of these elements significantly exceeding safety limits. Of these 59 traditional herbal preparations, intake estimates for 50 traditional herbal preparations significantly exceeded the safety limit for mercury (range = 1.4-1747 mg week(-1)); intake estimates for 26 traditional herbal preparations significantly exceeded the safety limit for arsenic (range = 0.53-427 mg week(-1)) and intake estimates for eight traditional herbal preparations were significantly above the safety limit for lead (range = 2.6-192 mg week(-1)). It is concluded that the mercury, arsenic, and lead contents of traditional herbal preparations used in Ayurveda, traditional Chinese medicine, and traditional Tibetan medicine remain a cause for concern and require strict control.

Hyperthyroidism caused by excessive consumption of sausages.

Hyperthyroidism results from excessive production of thyroid hormones. This is usually caused by Graves disease, but exogenous thyroid hormones can lead to similar symptoms. Recognition of the latter is difficult as excessive intake of thyroid hormone is not usually admitted nor recognised. To our knowledge, exogenous hyperthyroidism caused by thyroid-contaminated food has been described twice, but not in the Netherlands. A 77-year-old man presented at the Outpatient Department of Internal Medicine with lab values revealing hyperthyroidism. There were no abnormal findings at the physical examination. Antibodies against the thyroidstimulating hormone (TSH) receptor were not detectable. Thyroid scintigraphy with 123I showed an uptake of less than 1%. Silent thyroiditis was diagnosed and the natural course was awaited, but with no improvement in the thyroid values. The thyroglobulin was very low. Further anamnesis revealed an excessive daily consumption of sausages. Thyroid hormones were detectable in these sausages. After the patient stopped eating them, he became and remained euthyroid. The case stipulates the importance of a thorough anamnesis.

Inadvertent exposure to xenoestrogens.

Over the last 40 years there have been constant reports concerning environmental chemicals with hormone-like effects in wildlife. An endocrine disruptor is an exogenous substance that causes adverse health effects in an intact organism or its progeny, secondary to changes in endocrine function. Endocrine disruptors of widely diverse chemical structures that have oestrogenic properties are known as oestrogenic xenobiotics or xenoestrogens. Some of these substances, such as phytoestrogens and mycoestrogens, can come from diet or from the environment. Although the oestrogenic activity of these substances is weaker than that of oestradiol, new chemicals with endocrine disrupting potential continue to be discovered, inadvertent forms of exposure are constantly being identified, and there is increasing concern about cumulative effects. Studies in the 1960s and 1970s characterized the oestrogenicity of a number of industrial compounds and the pesticides o,p-DDT, kepone, methoxychlor, phenolic derivatives and polychlorinated biphenyls (PCBs). In the last 5 years, several environmental chemicals have been added to the list of xenoestrogens, including the pesticides toxaphene, dieldrin and endosulphan, and several different compounds used in the food industry, antioxidants such a t-butylhydroxyanisole; plasticizers such as benzylbutylphthalate and 4-OH-alkylphenols; and substances used in dental restorations, such as bisphenol-A. The relevance of these newly discovered endocrine disruptors to human health is now starting to emerge. The few studies that have investigated their effect in humans point in the same direction: if there is indeed an association between exposure to substances with hormone-disruptive activity and certain disorders of endocrine organs, the incidence of such disorders would be greater in areas where exposure to agents with this activity is high. A closer scrutiny is required to determine whether these newly discovered endocrine disrupting chemicals contribute, together with oestrogenic pesticides, to the exposure of humans to xenoestrogens.

Lowered methionine ingestion as responsible for the decrease in rodent mitochondrial oxidative stress in protein and dietary restriction possible i...

Available information indicates that long-lived mammals have low rates of reactive oxygen species (ROS) generation and oxidative damage at their mitochondria. On the other hand, many studies have consistently shown that dietary restriction (DR) in rodents also decreases mitochondrial ROS (mtROS) production and oxidative damage to mitochondrial DNA and proteins. It has been observed that protein restriction also decreases mtROS generation and oxidative stress in rat liver, whereas neither carbohydrate nor lipid restriction change these parameters. This is interesting because protein restriction also increases maximum longevity in rodents (although to a lower extent than DR) and is a much more practicable intervention for humans than DR, whereas neither carbohydrate nor lipid restriction seem to change rodent longevity. Moreover, it has been found that isocaloric methionine restriction also decreases mtROS generation and oxidative stress in rodent tissues, and this manipulation also increases maximum longevity in rats and mice. In addition, excessive dietary methionine also increases mtROS generation in rat liver. These studies suggest that the reduced intake of dietary methionine can be responsible for the decrease in mitochondrial ROS generation and the ensuing oxidative damage that occurs during DR, as well as for part of the increase in maximum longevity induced by this dietary manipulation. In addition, the mean intake of proteins (and thus methionine) of Western human populations is much higher than needed. Therefore, decreasing such levels to the recommended ones has a great potential to lower tissue oxidative stress and to increase healthy life span in humans while avoiding the possible undesirable effects of DR diets.

Concentration of mercury in hair of diseased people in Japan.

The purpose of this investigation was to estimate the total hair mercury of diseased people (not including patients of mercury poisoning such as Minamata disease). Hair samples were collected from 133 diseased volunteers in Tokyo and the surrounding areas from Oct. 1992 to June 1993. The total mercury concentrations in the hair of ordinary diseased people (atopic dermatitis, asthma, dementia, cerebral infarct, osteoporosis, hypertension and diabetes) were from 2.08 ppm to 36.5 ppm. Those values were considerably higher than that of healthy people of the same age groups. However, the uptake routes and the metabolic mechanism of high hair mercury concentrations in diseased people are not clear.

Wet deposition of fission-product isotopes to North America from the Fukushima Dai-ichi incident, March 2011.

Using the infrastructure of the National Atmospheric Deposition Program (NADP), numerous measurements of radionuclide wet deposition over North America were made for 167 NADP sites before and after the Fukushima Dai-ichi Nuclear Power Station incident of March 12, 2011. For the period from March 8 through April 5, 2011, wet-only precipitation samples were collected by NADP and analyzed for fission-product isotopes within whole-water and filterable solid samples by the United States Geological Survey using gamma spectrometry. Variable amounts of (131)I, (134)Cs, or (137)Cs were measured at approximately 21% of sampled NADP sites distributed widely across the contiguous United States and Alaska. Calculated 1- to 2-week individual radionuclide deposition fluxes ranged from 0.47 to 5100 Becquerels per square meter during the sampling period. Wet deposition activity was small compared to measured activity already present in U.S. soil. NADP networks responded to this complex disaster, and provided scientifically valid measurements that are comparable and complementary to other networks in North America and Europe.

Upregulation of lymphocyte apoptosis as a strategy for preventing and treating autoimmune disorders: a role for whole-food vegan diets, fish oil an...

Induced apoptosis of autoreactive T-lymphocyte precursors in the thymus is crucial for the prevention of autoimmune disorders. IGF-I and prolactin, which are lymphocyte growth factors, may have the potential to suppress apoptosis in thymocytes and thus encourage autoimmunity; conversely, dietary fish oil rich in omega-3 fats appears to upregulate apoptosis in lymphocytes. Since whole-food vegan diets may downregulate systemic IGF-I activity, it is proposed that such a diet, in conjunction with fish oil supplementation and treatment with dopamine agonists capable of suppressing prolactin secretion, may have utility for treating and preventing autoimmune disorders. This prediction is consistent with the extreme rarity of autoimmune disorders among sub-Saharan black Africans as long as they followed their traditional quasi-vegan lifestyles, and with recent ecologic studies correlating risks for IDDM and for multiple sclerosis mortality with animal product and/or saturated fat consumption. Moreover, there is evidence that vegan or quasi-vegan diets are useful in the management of rheumatoid arthritis, multiple sclerosis, and possibly SLE. The dopamine agonist bromocryptine exerts anti-inflammatory effects in rodent models of autoimmunity, and there is preliminary evidence that this drug may be clinically useful in several human autoimmune diseases; better tolerated D2-specific agonists such as cabergoline may prove to be more practical for use in therapy. The moderate clinical utility of supplemental fish oil in rheumatoid arthritis and certain other autoimmune disorders is documented. It is not unlikely that extra-thymic anti-inflammatory effects contribute importantly to the clinical utility of vegan diets, bromocryptine, and fish oil in autoimmunity. The favorable impact of low latitude or high altitude on autoimmune risk may be mediated by superior vitamin D status, which is associated with decreased secretion of parathyroid hormone; there are theoretical grounds for suspecting that parathyroid hormone may inhibit apoptosis in thymocytes. Androgens appear to up-regulate thymocyte apoptosis, may be largely responsible for the relative protection from autoimmunity enjoyed by men, and merit further evaluation for the management of autoimmunity in women. It will probably prove more practical to prevent autoimmune disorders than to reverse them once established; a whole-food vegan diet, coupled with fish oil and vitamin D supplementation, may represent a practical strategy for achieving this prevention, while concurrently lowering risk for many other life-threatening 'Western' diseases. Copyright 2001 Harcourt Publishers Ltd.

The flip side of immune surveillance: immune dependency.

The growths of many and perhaps all tumors may be stimulated rather than inhibited by a quantitatively low level of immunity. The reason tumors have antigens may be that tumors do not develop in vivo in the absence of at least a minimal immune reaction; in this sense, cancer may be considered an autoimmune disease. This review, based largely on the work of our own laboratory, outlines the data showing that the titration of anti-tumor immunity exhibits the phenomenon of hormesis, i.e. the dose-response curve is non-linear such that low levels of immunity are generally stimulatory but larger quantities of the same immune reactants may inhibit tumor growth. Evidence is also reviewed that suggests that the immune response may vary qualitatively and quantitatively during progression, such that there seems to be, during oncogenesis, a very low level of immune reaction that aids initial tumor growth, followed by a larger reaction that may cause remission of early neoplasms, followed, if the neoplasm survives, by a relative immunologic tolerance to the tumor that may be dependent, at least in part, on suppressor cells. This knowledge may help to explain some clinical observations concerning the relationships among tumor types and the organ distribution of metastases.

Childhood soy intake and breast cancer risk in Asian American women.

INTRODUCTION: Historically, breast cancer incidence has been substantially higher in the United States than in Asia. When Asian women migrate to the United States, their breast cancer risk increases over several generations and approaches that for U.S. Whites. Thus, modifiable factors, such as diet, may be responsible. METHODS: In this population-based case-control study of breast cancer among women of Chinese, Japanese, and Filipino descent, ages 20 to 55 years, and living in San Francisco-Oakland (California), Los Angeles (California) and Oahu (Hawaii), we interviewed 597 cases (70% of those eligible) and 966 controls (75%) about adolescent and adult diet and cultural practices. For subjects with mothers living in the United States (39% of participants), we interviewed mothers of 99 cases (43% of eligible) and 156 controls (40%) about the daughter's childhood exposures. Seventy-three percent of study participants were premenopausal at diagnosis. RESULTS: Comparing highest with lowest tertiles, the multivariate relative risks (95% confidence interval) for childhood, adolescent, and adult soy intake were 0.40 (0.18-0.83; P(trend) = 0.03), 0.80 (0.59-1.08; P(trend) = 0.12), and 0.76 (0.56-1.02; P(trend) = 0.04), respectively. Inverse associations with childhood intake were noted in all three races, all three study sites, and women born in Asia and the United States. Adjustment for measures of westernization attenuated the associations with adolescent and adult soy intake but did not affect the inverse relationship with childhood soy intake. DISCUSSION: Soy intake during childhood, adolescence, and adult life was associated with decreased breast cancer risk, with the strongest, most consistent effect for childhood intake. Soy may be a hormonally related, early-life exposure that influences breast cancer incidence.

Dietary and clastogenic factors in children who immigrated to Israel from regions contaminated by the Chernobyl accident.

The authors evaluated the possible association between dietary history and plasma clastogenic factors in children who immigrated to Israel between 1989 and 1993 from regions contaminated by the Chernobyl accident. The authors compared questionnaire data about demographic variables, dietary histories before and after immigration occurred, and health status with clastogenic factor scores for 162 immigrants. Logistic regression analysis revealed a negative association between clastogenic factor scores and frequency of consumption of fresh vegetables and fruit among children < or = 7 yr of age during the postimmigration period. Intake of eggs and fish by boys who were < or = 7 yr of age prior to immigration was associated positively with clastogenic factor scores. Consumption of fresh vegetables and fruits afforded protection to the immune systems of children who were < or = 7 yr of age.

Vitamin D supplement doses and serum 25-hydroxyvitamin D in the range associated with cancer prevention.

BACKGROUND: Studies indicate that intake of vitamin D in the range from 1,100 to 4,000 IU/d and a serum 25-hydroxyvitamin D concentration [25(OH)D] from 60-80 ng/ml may be needed to reduce cancer risk. Few community-based studies allow estimation of the dose-response relationship between oral intake of vitamin D and corresponding serum 25(OH)D in the range above 1,000 IU/d. MATERIALS AND METHODS: A descriptive study of serum 25(OH)D concentration and self-reported vitamin D intake in a community-based cohort (n = 3,667, mean age 51.3 ± 13.4 y). RESULTS: Serum 25(OH)D rose as a function of self-reported vitamin D supplement ingestion in a curvilinear fashion, with no intakes of 10,000 IU/d or lower producing 25(OH)D values above the lower-bound of the zone of potential toxicity (200 ng/ml). Unsupplemented all-source input was estimated at 3,300 IU/d. The supplemental dose ensuring that 97.5% of this population achieved a serum 25(OH)D of at least 40 ng/ml was 9,600 IU/d. CONCLUSION: Universal intake of up to 40,000 IU vitamin D per day is unlikely to result in vitamin D toxicity.

The effect of caffeine on intraocular pressure: a systematic review and meta-analysis.

BACKGROUND: Caffeine is widely consumed, and its effect on intraocular pressure (IOP) has been reported in conflicting data. The aim of this meta-analysis was to quantitatively summarize the effect of caffeine on IOP in normal individuals and in patients with glaucoma or ocular hypertension (OHT). METHODS: A comprehensive literature search was performed using the Cochrane Collaboration methodology to identify pertinent randomized controlled trials (RCTs) from the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed and EMBASE. A systematic review and meta-analysis was performed. IOP at 0.5 hour (h), 1 h and 1.5 h after caffeine ingestion was the main outcome measurement. RESULTS: Six RCTs (two parallel-designed and four crossover-designed) evaluating 144 participants fulfilled inclusion criteria. The risk of bias for these studies was uncertain. Among the participants, 103 were normal individuals and 41 were patients with glaucoma or OHT. In normal individuals, the IOPs measured at 0.5 h, 1 h and 1.5 h post-intervention were not affected by ingestion of caffeine. The weighted mean difference (WMD) with 95% confidence intervals (95%CI) for each measurement point were -0.740 (-2.454, 0.974), 0.522 (-0.568, 1.613) and 0.580 (-1.524, 2.684). However, in patients with glaucoma or OHT, IOP increased at each measurement point, with the WMD and 95%CI being 0.347 (0.078, 0.616), 2.395 (1.741,3.049) and 1.998 (1.522,2.474) respectively. No publication bias was detected by either Begg's or Egger's test. CONCLUSION: Available evidences showed that caffeine had different effects on IOP in different groups of individuals. For normal individuals, IOP was not changed by ingestion of caffeine, while for patients with glaucoma or OHT, IOP increased significantly. More high-quality RCTs are warranted to confirm this. The mechanisms underlying this phenomenon and the clinical significance are to be explored.

The use of dental radiographs: update and recommendations.

BACKGROUND AND OVERVIEW: The National Council on Radiation Protection & Measurements updated its recommendations on radiation protection in dentistry in 2003, the Centers for Disease Control and Prevention published its Guidelines for Infection Control in Dental Health-Care Settings in 2003, and the U.S. Food and Drug Administration updated its selection criteria for dental radiographs in 2004. This report summarizes the recommendations presented in these documents and addresses additional topics such as patient selection criteria, film selection for conventional radiographs, collimation, beam filtration, patient protective equipment, film holders, operator protection, film exposure and processing, infection control, quality assurance, image viewing, direct digital radiography and continuing education of dental health care workers who expose radiographs. CONCLUSIONS: This report discusses implementation of proper radiographic practices. In addition to these guidelines, dentists should be aware of, and comply with, applicable federal and state regulations. CLINICAL IMPLICATIONS: Dentists should weigh the benefits of dental radiographs against the consequences of increasing a patient's exposure to radiation and implement appropriate radiation control procedures.

Dietary seaweed modifies estrogen and phytoestrogen metabolism in healthy postmenopausal women.

Seaweed and soy foods are consumed daily in Japan, where breast cancer rates for postmenopausal women are significantly lower than in the West. Likely mechanisms include differences in diet, especially soy consumption, and estrogen metabolism. Fifteen healthy postmenopausal women participated in this double-blind trial of seaweed supplementation with soy challenge. Participants were randomized to 7 wk of either 5 g/d seaweed (Alaria) or placebo (maltodextrin). During wk 7, participants also consumed a daily soy protein isolate (2 mg isoflavones/kg body weight). After a 3-wk washout period, participants were crossed over to the alternate supplement schedule. There was an inverse correlation between seaweed dose (mg/kg body weight) and serum estradiol (E2) (seaweed-placebo = y = -2.29 x dose + 172.3; r = -0.70; P = 0.003), [corrected] which was linear across the range of weights. Soy supplementation increased urinary daidzein, glycitein, genistein, and O-desmethylangolensin (P = 0.0001) and decreased matairesinol and enterolactone (P < 0.05). Soy and seaweed plus soy (SeaSoy) increased urinary excretion of 2-hydroxyestrogen (2-OHE) (P = 0.0001) and the ratio of 2-OHE:16alpha-hydroxyestrone (16alphaOHE(1)) (P = 0.01). For the 5 equol excretors, soy increased urinary equol excretion (P = 0.0001); the combination of SeaSoy further increased equol excretion by 58% (P = 0.0001). Equol producers also had a 315% increase in 2:16 ratio (P = 0.001) with SeaSoy. Seaweed favorably alters estrogen and phytoestrogen metabolism and these changes likely include modulation of colonic bacteria.

Evaluation of the genotoxicity of stevioside and steviol using six in vitro and one in vivo mutagenicity assays.

Stevioside, a constituent of Stevia rebaudiana, is commonly used as a non-caloric sugar substitute in Japan. The genetic toxicities of stevioside and its aglycone, steviol, were examined with seven mutagenicity tests using bacteria (reverse mutation assay, forward mutation assay, umu test and rec assay), cultured mammalian cells (chromosomal aberration test and gene mutation assay) and mice (micronucleus test). Stevioside was not mutagenic in any of the assays examined. The aglycone, steviol, however, produced dose-related positive responses in some mutagenicity tests, i.e. the forward mutation assay using Salmonella typhimurium TM677, the chromosomal aberration test using Chinese hamster lung fibroblast cell line (CHL) and the gene mutation assay using CHL. Metabolic activation systems containing 9000 g supernatant fraction (S9) of liver homogenates prepared from polychlorinated biphenyl or phenobarbital plus 5,6-benzoflavone-pretreated rats were required for mutagenesis and clastogenesis. Steviol was weakly positive in the umu test using S.typhimurium TA1535/pSK1002 either with or without the metabolic activation system. Steviol, even in the presence of the S9 activation system, was negative in other assays, i.e. the reverse mutation assays using S.typhimurium TA97, TA98, TA100, TA102, TA104, TA1535, TA1537 and Escherichia coli WP2 uvrA/pKM101 and the rec-assay using Bacillus subtilis. Steviol was negative in the mouse micronucleus test. The genotoxic risk of steviol to humans is discussed.

Tolerable upper intake levels for trans fat, saturated fat, and cholesterol.

Tolerable upper intake levels (ULs) set by the Institute of Medicine (IOM) are important, in part because they are used for estimating the percentage of the population at potential risk of adverse effects from excessive nutrient intake. The IOM did not set ULs for trans fat, saturated fat, and cholesterol because any intake level above 0% of energy increased LDL cholesterol concentration and these three food components are unavoidable in ordinary diets. The purpose of the analysis presented in this review was to evaluate clinical trial and prospective observational data that were not previously considered for setting a UL with the aim of determining whether the current UL model could be used for saturated fat, trans fat, and cholesterol. The results of this analysis confirm the limitations of the risk assessment model for setting ULs because of its inability to identify a UL for food components, such as cholesterol, that lack an intake threshold associated with increased chronic disease risk. © 2011 International Life Sciences Institute.

Justification of diagnostic medical exposures: some practical issues. Report of an International Atomic Energy Agency Consultation

Objectives The Radiation Protection of Patients Unit of the International Atomic Energy Agency (IAEA) is concerned about the effectiveness of justification of diagnostic medical exposures. Recent published work and the report of an initial IAEA consultation in the area gave grounds for such concerns. There is a significant level of inappropriate usage, and, in some cases, a poor level of awareness of dose and risk among some key groups involved. This article aims to address this. Methods The IAEA convened a second group of experts in November 2008 to review practical and achievable actions that might lead to more effective justification. Results This report summarises the matters that this group considered and the outcome of their deliberations. There is a need for improved communication, both within professions and between professionals on one hand, and between professionals and the patients/public on the other. Coupled with this, the issue of consent to imaging procedures was revisited. The need for good evidence-based referral guidelines or criteria of acceptability was emphasised, as was the need for their global adaptation and dissemination. Conclusion Clinical audit was regarded as a key tool in ensuring that justification becomes an effective, transparent and accountable part of normal radiological practice. In summary, justification would be facilitated by the “3 As”: awareness, appropriateness and audit.

Direct and indirect cellular effects of aspartame on the brain.

The use of the artificial sweetener, aspartame, has long been contemplated and studied by various researchers, and people are concerned about its negative effects. Aspartame is composed of phenylalanine (50%), aspartic acid (40%) and methanol (10%). Phenylalanine plays an important role in neurotransmitter regulation, whereas aspartic acid is also thought to play a role as an excitatory neurotransmitter in the central nervous system. Glutamate, asparagines and glutamine are formed from their precursor, aspartic acid. Methanol, which forms 10% of the broken down product, is converted in the body to formate, which can either be excreted or can give rise to formaldehyde, diketopiperazine (a carcinogen) and a number of other highly toxic derivatives. Previously, it has been reported that consumption of aspartame could cause neurological and behavioural disturbances in sensitive individuals. Headaches, insomnia and seizures are also some of the neurological effects that have been encountered, and these may be accredited to changes in regional brain concentrations of catecholamines, which include norepinephrine, epinephrine and dopamine. The aim of this study was to discuss the direct and indirect cellular effects of aspartame on the brain, and we propose that excessive aspartame ingestion might be involved in the pathogenesis of certain mental disorders (DSM-IV-TR 2000) and also in compromised learning and emotional functioning.

Urinary cadmium in the 1999-2008 U.S. National Health and Nutrition Examination Survey (NHANES).

Chronic low-level cadmium (Cd) exposure is linked to kidney and cardiovascular disease, fractures, and cancer. Diet and smoking are primary sources of exposure in the general population. We analyzed urinary Cd in NHANES 1999-2008 to determine whether levels declined significantly over the decade for U.S. children, teens, and adults (nonsmokers and smokers) and, if so, factors influencing the decline(s). For each subpopulation, we modeled log urinary Cd using variable-threshold censored multiple regression. Models included individual-level covariates (age, gender, BMI, income, race/ethnicity/country of origin, education, survey period), smoking, housing (home age, water source, filter use), and diet (supplement use; 24-h calorie, fat, protein, micronutrient, and Cd-containing food intakes), creatinine, and survey year variables. Geometric mean urinary Cd (ng/mL) declined 20-25% in these subpopulations, and the regressions showed statistically significant declines in later years for teens and adults. While certain covariates were significantly associated with Cd by subpopulation (creatinine; age; BMI; race/ethnicity/origin; education; smokers in the home; serum cotinine; 24-h fat, Mg, Fe intakes; use of dietary supplements), they did not help explain the declines. Instead, unidentified time-related factors appeared responsible. Despite the declines, millions of Americans remain potentially at risk of adverse outcomes associated with low-level Cd exposure.

Circulating insulin-like growth factor (IGF) peptides and prostate cancer risk: a systematic review and meta-analysis

Insulin-like growth factors (IGF-I, IGF-II) and their binding proteins (IGFBP-1-6) play a key role in cell proliferation, differentiation and apoptosis, suggesting possible involvement in carcinogenesis. Several epidemiological studies show associations of IGFs with prostate cancer. We searched the published literature for all studies relating levels of IGFs or IGFBPs with prostate cancer. We performed random effects meta-analysis to calculate summary odds ratios. The number of studies (prostate cancer cases) included in each meta-analysis were 42 (7,481) IGF-I; 10 (923) IGF-II; 3 (485) IGFBP-1; 5 (577) IGFBP-2; 29 (6,541) IGFBP-3; and 11 (3,545) IGF-1:IGFBP-3 ratio. The pooled odds ratios (95% confidence intervals) per standard deviation increase in peptide, were: IGF-I, OR = 1.21 (1.07, 1.36); IGF-II, OR = 1.17 (0.93, 1.47); IGFBP-1, OR = 1.21 (0.62, 2.33); IGFBP-2, OR = 1.18 (0.90, 1.54); IGFBP-3, OR = 0.88 (0.79, 0.98); IGFI:IGFBP-3 ratio, OR = 1.10 (0.97, 1.24). For all exposures, there was substantial heterogeneity (all I2 > 75%), partly explained by study design: the magnitude of associations was smaller in prospective versus retrospective studies, and for IGFBP-3 the inverse association with prostate cancer risk was seen in retrospective but not prospective studies. There was weak evidence that associations of IGF-I and IGFBP-3 with prostate cancer were stronger for advanced disease. Our meta-analysis confirms that raised circulating lGF-I is positively associated with prostate cancer risk. Associations between IGFBP-3 and prostate cancer were inconsistent, and there was little evidence for a role of IGF-II, IGFBP-1 or IGFBP-2 in prostate cancer risk.

Methylmercury Exposure and Incident Diabetes in U.S. Men and Women in Two Prospective Cohorts

OBJECTIVE Emerging in vitro and animal evidence suggests that methylmercury could increase type 2 diabetes, but little evidence exists in humans. We aimed to prospectively determine associations of mercury exposure, as assessed by biomarker measurement, with incident diabetes. RESEARCH DESIGN AND METHODS We used neutron activation analysis to measure toenail mercury, an objective biomarker of methylmercury exposure, in 9,267 adults free of diabetes at baseline in two separate U.S. prospective cohorts. Incident diabetes was identified from biennial questionnaires and confirmed by validated supplementary questionnaire using symptoms, diagnostic tests, and medical therapy. Associations of mercury exposure with incident diabetes were assessed using Cox proportional hazards. RESULTS During mean ± SD follow-up of 19.7 ± 7.0 years, 1,010 new cases of diabetes were diagnosed. The 95th percentile of toenail mercury was 1.32 μg/g in men and 0.76 μg/g in women, corresponding to exposures ∼3.5-fold and 2-fold higher than the U.S. Environmental Protection Agency reference dose. In multivariable analyses, toenail mercury concentrations were not associated with higher incidence of diabetes in women, men, or both cohorts combined. Comparing the highest to lowest quintile of exposure, the hazard ratio (95% CI) for incident diabetes was 0.86 (0.66–1.11) in women, 0.69 (0.42–1.15) in men, and 0.77 (0.61–0.98) in the combined cohorts. Findings were similar when more extreme categories (deciles) of mercury were compared, and in analyses stratified by fish or omega-3 consumption, BMI, and age. CONCLUSIONS These findings from two separate large prospective cohorts do not support adverse effects of methylmercury on development of diabetes in men or women at usual levels of exposure seen in these populations.

Dietary intake of n−3 and n−6 fatty acids and the risk of clinical depression in women: a 10-y prospective follow-up study

Background: The associations between different sources of dietary n−3 (omega-3) and n−6 (omega-6) fatty acids and the risk of depression have not been prospectively studied. Objective: The objective was to examine the relation between different n−3 and n−6 types with clinical depression incidence. Design: We prospectively studied 54,632 US women from the Nurses' Health Study who were 50–77 y of age and free from depressive symptoms at baseline. Information on diet was obtained from validated food-frequency questionnaires. Clinical depression was defined as reporting both physician-diagnosed depression and regular antidepressant medication use. Results: During 10 y of follow-up (1996–2006), 2823 incident cases of depression were documented. Intake of long-chain n−3 fatty acids from fish was not associated with depression risk [relative risk (RR) for 0.3-g/d increment: 0.99; 95% CI: 0.88, 1.10], whereas α-linolenic acid (ALA) intake was inversely associated with depression risk (multivariate RR for 0.5-g/d increment: 0.82; 95% CI: 0.71, 0.94). The inverse association between ALA and depression was stronger in women with low linoleic acid (LA) intake (P for interaction = 0.02): a 0.5-g/d increment in ALA was inversely associated with depression in the first, second, and third LA quintiles [RR (95% CI): 0.57 (0.37, 0.87), 0.62 (0.41, 0.93), and 0.68 (0.47, 0.96), respectively] but not in the fourth and fifth quintiles. Conclusions: The results of this large longitudinal study do not support a protective effect of long-chain n−3 from fish on depression risk. Although these data support the hypothesis that higher ALA and lower LA intakes reduce depression risk, this relation warrants further investigation.

Prospective studies of dietary alpha-linolenic acid intake and prostate cancer risk: a meta-analysis.

Individual-based studies that investigated the relation between dietary alpha-linolenic acid (ALA) intake and prostate cancer risk have shown inconsistent results. We carried out a meta-analysis of prospective studies to examine this association. We systematically searched studies published up to December 2008. Log relative risks (RRs) were weighted by the inverse of their variances to obtain a pooled estimate with its 95% confidence interval (CI). We identified five prospective studies that met our inclusion criteria and reported risk estimates by categories of ALA intake. Comparing the highest to the lowest ALA intake category, the pooled RR was 0.97 (95% CI:0.86-1.10) but the association was heterogeneous. Using the reported numbers of cases and non-cases in each category of ALA intake, we found that subjects who consumed more than 1.5 g/day of ALA compared with subjects who consumed less than 1.5 g/day had a significant decreased risk of prostate cancer: RR = 0.95 (95% CI:0.91-0.99). Divergences in results could partly be explained by differences in sample sizes and adjustment but they also highlight limits in dietary ALA assessment in such prospective studies. Our findings support a weak protective association between dietary ALA intake and prostate cancer risk but further research is needed to conclude on this question.

Quantification of the neurotoxic beta-carboline harmane in barbecued/grilled meat samples and correlation with level of doneness.

Harmane, one of the heterocyclic amines (HCAs), is a potent neurotoxin linked to human diseases. Dietary exposure, especially in cooked meats, is the major source of exogenous exposure for humans. However, knowledge of harmane concentrations in cooked meat samples is limited. Our goals were to (1) quantify the concentration of harmane in different types of cooked meat samples, (2) compare its concentration to that of other more well-understood HCAs, and (3) examine the relationship between harmane concentration and level of doneness. Thirty barbecued/grilled meat samples (8 beef steak, 12 hamburger, 10 chicken) were analyzed for harmane and four other HCAs (2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine [PhIP], amino-3,8-dimethylimidazo[4,5-f]quinoxaline [MeIQx], 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline [DiMeIQx], and 2-amino-1,6-dimethylfuro[3,2-e]imidazo[4,5-b]pyridine [IFP]). Mean (+/- SD) harmane concentration was 5.63 (+/- 6.63) ng/g; harmane concentration was highest in chicken (8.48 +/- 9.86 ng/g) and lowest in beef steak (3.80 +/- 3.6 ng/g). Harmane concentration was higher than that of the other HCAs and significantly correlated with PhIP concentration. Harmane concentration was associated with meat doneness in samples of cooked beef steak and hamburger, although the correlation between meat doneness and concentration was greater for PhIP than for harmane. Evidence indicates that harmane was detectable in nanograms per gram quantities in cooked meat (especially chicken) and, moreover, was more abundant than other HCAs. There was some correlation between meat doneness and harmane concentration, although this correlation was less robust than that observed for PhIP. Data such as these may be used to improve estimation of human dietary exposure to this neurotoxin.

Influence of tea drinking on manganese intake, manganese status and leucocyte expression of MnSOD and cytosolic aminopeptidase P.

OBJECTIVE: Since black tea contains high levels of manganese (Mn), we investigated the relationship between dietary Mn intake, circulating Mn levels and leucocyte expression of two Mn-dependent enzymes in tea drinkers and non-tea drinkers. DESIGN: We assessed Mn intakes (food frequency questionnaire), fasting whole blood and plasma Mn levels, and quantitative expression of peripheral blood mononuclear cell Mn-dependent superoxide dismutase (MnSOD) and cytosolic aminopeptidase-P (cAP-P). SETTING AND SUBJECTS: In total, 24 tea drinkers (> or = 1 l black tea/day) and 28 non-tea drinkers were recruited from the staff and students of King's College London by circular email. RESULTS: Dietary Mn intakes (mean (range)) were significantly lower (P < 0.0001) in non tea drinkers (3.2 mg/day (0.5-6.5)) than tea drinkers (5.5 mg/day (2-12) or 10 mg/day (5-20) depending upon the value used for Mn levels of black tea). Whole blood, plasma Mn levels and expression of MnSOD and cAP-P did not differ between the groups. In a continuous analysis, whole blood Mn levels and expression of MnSOD correlated inversely but no other parameters associated with each other. CONCLUSIONS: Tea drinking is a major source of dietary Mn and intakes commonly exceed proposed adequate intake values of 1.8-2.3 mg Mn/day and, on occasion, exceed upper limits of 10-11 mg/day. Dietary Mn intake has little influence on markers of Mn status or expression of Mn-dependent enzymes. Fasting whole blood Mn levels and leucocyte expression of MnSOD could, together, be further investigated as markers of Mn status.

A critical review of the genetic toxicity of steviol and steviol glycosides.

Extracts of the leaves of the stevia plant (Stevia rebaudiana Bertoni) are used to sweeten food and beverages in South America, Japan and China. The components responsible for the sweet properties of the plant are glycosides of steviol, primary stevioside (ent-13-hydroxykaur-16-en-18-oic acid), which is 250-300 times sweeter than sucrose and rebaudiosides A and C. Stevioside and steviol have been subjected to extensive genetic testing. The majority of the findings show no evidence of genotoxic activity. Neither stevioside nor its aglycone steviol have been shown to react directly with DNA or demonstrate genotoxic damage in assays relevant to human risk. The mutagenic activity of steviol and some of its derivatives, exhibited in strain TM677, was not reproduced in the same bacteria having normal DNA repair processes. The single positive in vivo study measuring single-strand DNA breaks in Wistar rat tissues by stevioside, was not confirmed in experiments in mice and appears to be measuring processes other than direct DNA damage. Neither stevioside nor steviol-induced clastogenic effects at extremely high dose levels in vivo. Application of a Weight-of-Evidence approach to assess the genetic toxicology database concludes that these substances do not pose a risk of genetic damage following human consumption.

Towards prevention of vitamin D deficiency and beyond: knowledge gaps and research needs in vitamin D nutrition and public health.

The North American Institute of Medicine (IOM) recently published their report on dietary reference intakes (DRI) for Ca and vitamin D. The DRI committee's deliberations underpinning this most comprehensive report on vitamin D nutrition to date benefited hugely from a much expanded knowledge base in vitamin D over the last decade or more. However, since their release, the vitamin D DRI have been the subject of intense controversy, which is largely due to the persistence of fundamental knowledge gaps in vitamin D. These can be identified at the levels of exposure, metabolism, storage, status, dose-response, function and beneficial or adverse health effects, as well as safe and effective application of intake recommendations at the population level through sustainable food-based approaches. The present review provides a brief overview of the approach used by the IOM committee to revise the DRI for vitamin D and to collate from a number of authoritative sources key knowledge gaps in vitamin D nutrition from the public health perspective. A number of research topics are outlined and data requirements within these are identified and mapped to the risk assessment framework used by the DRI committee. While not intended as an exhaustive list, it provides a basis for organising and prioritising research efforts in the area of vitamin D, which may offer a perspective on the major areas in need of attention. It is intended to be of use to researchers, national policy makers, the public health community, industry groups and other relevant stakeholders including funding institutions.