Tuesday, August 11, 2009



Lead, a proven neurotoxin linked to learning and behavioral disorders, is one of the most studied heavy metals. Exposure to lead can cause learning, language and behavioral problems such as lowered IQ, impulsiveness, reduced school performance, increased aggression, seizures and brain damage, anemia, and, after long exposure, damage to the kidneys. Lead has also been linked to miscarriage, reduced fertility in both men and women, hormonal changes, menstrual irregularities and delays in the onset of puberty in girls. Pregnant women and young children exposed to lead are particularly vulnerable. Lead easily crosses the placenta and enters the fetal brain, where it interferes with normal where it interferes with normal development. Increased blood levels of lead early in life can result in decreased attention span, reading disabilities and failure to graduate from high school.

The troubling story of lead is almost 3,000 years old. Greek physicians and Roman architects were describing the symptoms of lead poisoning – blindness, convulsions, brain damage, kidney disease and cancer – in 100 B.C. One hundred years ago, lead poisoning in children was linked to the use of lead‐based paints. By 1909, this new science had resulted in laws in France, Austria and Belgium banning paint made with white lead. As the science got stronger, the League of Nations and more countries – including Greece, Great Britain, Tunisia, Spain, Sweden and Cuba – also banned lead. The United States did not. A U.S. trade group, the Lead Industry Association (LIA), responded to the science by mounting the White Lead Promotion Campaign ʺto offset the stigma attached to lead because of attacks made upon it by consumer organizations.ʺ In 1943, the first studies came out showing that lead could create health problems for children at much lower levels of exposure than tose linked to poisoning symptoms. The science began to mount that some behavioral disorders, attention deficit and learning disabilities were coming from household exposure to lead paint and from air pollution caused bylead in gasoline. But lead manufacturers disputed these studies. Having admitted that lead was a poison in 1920, the industry argued that the levels of exposure from lead chips in a home or the fumes from the lead additives in gasoline wer too small to be dangerous. The industry‐motivated obfuscation of the science delayed U.S. government action on lead until the 1970s. In the three decades since the laws phasing out lead in paint and gasoline were passed, blood lead levels in the United States have declined dramatically, according to biomonitoring studies. But that good news is tempered by the bad news that the last 30 years of research have also demonstrated that lead can cause oher health problems and can have effects at much lower levels of exposure than previously considered harmful. The most recent studies conclude that there is no safe level of lead. No amount of exposure is without harm. Miscarriage, reduced fertility in both men and women, hormonal changes, menstrual irregularities and delays in when puberty begins for girls have all been linked to lead exposure. At puberty, boys’ developing testes appear to be especially vulnerable to lead’s impact. Given that lead does not break down in the body but accumulates over time, small amounts of lead can add up to harm. For inner‐city communities where children and adults have higher levels of lead from old paint in buildings and old water pipes, the lead in lipstick is unnecessarily adding to levels of harm that are already too high.

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