Comment: Lead poisoning and exposure was also pervasive in the 1970s

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Lead poisoning and exposure was also pervasive in the 1970s

"Lead has been recognized as a poison for thousands of years, but the profound impact that chronic exposure to even low levels of lead can have on developing children only became widely recognized in the United States in the 1970s. At that time, it was not uncommon for pediatricians to see lead poisoning cases in which the children had blood lead levels greater than or equal to 45 micrograms per deciliter (µg/dL), at which point children often exhibit both neurological problems and anemia. At higher blood lead levels (70-100 µg/dL), children can suffer from comas and seizures, or even die. "

http://www.environment.ucla.edu/reportcard/article.asp?paren...

"It is clear that blood lead levels have fallen significantly over the last 40 years. During the 1970s, childhood blood lead concentrations of 40 μg/dL were not unusual. The available evidence suggests that mean blood lead levels are now in the range 2–4 μg/dL in the United States and much of Europe."

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1247191/

http://kidshealth.org/parent/medical/brain/lead_poisoning.html