CNS, Centralnervoussystem;CO, carbonmonoxide;DDT, dichlorodiphenyltrichloroethane;GI,gastrointestinal.DatafromLeighJP,MarkowitzSB,FahsM,etal:OccupationalinjuryandillnessintheUnitedStates:estimatesofcosts,morbidity,andmortality,Arch Intern Med 157:1557,1997;MitchellFL:Hazardouswaste.InRomWN,editor:Environmental and occupational medicine, ed2,Boston,1992,Little,Brown,pp1275;andLeviPE:Classesoftoxicchemicals.InHodgsonE,LeviPE,editors:A textbook of modern toxicology, Stamford,CT,1997,Appleton&Lange,pp229.
as pesticides are DDT (dichlorodiphenyltrichloroethane) and its metabolites, and agents such as lindane, aldrin, and dieldrin. Nonpesticide organochlorines include polychlorinated biphenyls (PCBs) and dioxin (TCDD [2,3,7,8-tetrachlorodibenzo-p-dioxin]). DDT was banned in the United States in 1973, but more than half of the population have detectable serum levels of p,p′DDE, a long-lasting DDT metabolite, including those born after the ban on DDT went into effect. PCB and TCDD also are present in the blood of most of the U.S. population. Acute DDT poisoning in humans causes neurologic toxicity. Most organochlorines are endocrine disruptors and have anti-estrogenic or anti-androgenic activity in laboratory animals, but long-term health effects in humans have not been firmly established.
Nonpesticide organochlorines include polychlorinated biphenyls (PCBs) and dioxin (TCDD [2,3,7,8-tetrachlorodibenzo-p-dioxin]). Dioxins and PCBs can cause skin disorders such as folliculitis and acneiform dermatosis known as chloracne, which consists of acne, cyst formation, hyperpigmentation, and hyperkeratosis, generally around the face and behind the ears. It can be accompanied by abnormalities in the liver and CNS. Because PCBs induce the P-450 enzyme system, workers exposed to these substances may show altered drug metabolism. Environmental disasters in Japan and China in the late 1960s caused by the consumption of rice oil contaminated by PCBs poisoned about 2000 people in each episode. The primary manifestations of the disease (yusho in Japan, yu-cheng in China) were chloracne and hyperpigmentation of the skin and nails.
Bisphenol A (BPA) is used in the synthesis of polycarbonate food and water containers and of epoxy resins that line almost all food bottles and cans; as a result, exposure to BPA is virtually ubiquitous in humans. BPA has long been known as a potential endocrine disruptor. Several large retrospective studies have linked elevated urinary BPA levels to heart disease in adult populations. In addition, infants who drink from BPA-containing containers may be particularly susceptible to BPA’s endocrine effects. In 2010, Canada was the first country to list BPA as a toxic substance, and the largest makers of baby bottles and “sippy” cups have stopped using BPA in the manufacturing process. The extent of the human health risks associated with BPA remains uncertain, however, and requires further study.
Vinyl chloride, used in the synthesis of polyvinyl resins, can cause angiosarcoma of the liver, a rare type of liver tumor.