X-rays may also reveal lead-containing foreign materials such as paint chips in the gastrointestinal tract.Fecal lead content that is measured over the course of a few days may also be an accurate way to estimate the overall amount of childhood lead intake. This form of measurement may serve as a useful way to see the extent of oral lead exposure from all the diet and environmental sources of lead.Lead poisoning shares symptoms with other conditions and may be easily missed. Conditions that present similarly and must be ruled out in diagnosing lead poisoning include carpal tunnel syndrome, Guillain–Barré syndrome, renal colic, appendicitis, encephalitis in adults, and viral gastroenteritis in children. Other differential diagnoses in children include constipation, abdominal colic, iron deficiency, subdural hematoma, neoplasms of the central nervous system, emotional and behavior disorders, and intellectual disability. Reference levels
The current reference range for acceptable blood lead concentrations in healthy persons without excessive exposure to environmental sources of lead is less than 3.5 µg/dL for children. It was less than 25 µg/dL for adults. Previous to 2012 the value for children was 10 (µg/dl). Lead-exposed workers in the U.S. are required to be removed from work when their level is greater than 50 µg/dL if they do construction and otherwise greater than 60 µg/dL.In 2015, US HHS/CDC/NIOSH designated 5 µg/dL (five micrograms per deciliter) of whole blood, in a venous blood sample, as the reference blood lead level for adults. An elevated BLL is defined as a BLL ≥5 µg/dL.
Also in the 18th century, "Devonshire colic" was the name given to the symptoms experienced by people of Devon who drank cider made in presses that were lined with lead. Lead was added to cheap wine illegally in the 18th and early 19th centuries as a sweetener. The composer Beethoven, a heavy wine drinker, had elevated lead levels (as later detected in his hair) possibly due to this; the cause of his death is controversial, but lead poisoning is a contender as a factor.With the Industrial Revolution in the 19th century, lead poisoning became common in the work setting. The introduction of lead paint for residential use in the 19th century increased childhood exposure to lead; for millennia before this, most lead exposure had been occupational. William James Furnival (1853-1928), research ceramist of City & Guilds London Institute, appeared before Parliament in 1901 and presented a decades evidence to convince the nations leaders to remove lead completely from the British ceramic industry. His 852-page treatise, Leadless Decorative Tiles, Faience, and Mosaic of 1904 published that campaign and provided recipes to promote lead-free ceramics. At the request of the Illinois state government, Alice Hamilton (1869-1970) documented lead toxicity in Illinois industry and in 1911 presented results to the 23rd Annual Meeting of the American Economic Association. Dr. Hamilton was a founder of the field of occupational safety and health and published the first edition of her manual, Industrial Toxicology in 1934, yet in print in revised forms.