More on Lead Poisoning: Even Small Amounts of Lead Linked To Reduced IQ
A newly-released study, done over the course of six years by researchers at Cornell University, finds that even small amounts of lead in children's blood (below CDC guidelines for acceptable levels) make reduced IQ much more likely. This correlation holds true even when other factors that affect IQ--such as other environmental factors or genetics--are accounted for.
The Centers for Disease Control and Prevention (CDC) say that the maximum allowable blood-lead level is 10 micrograms per deciliter. But the new Cornell study focused on kids with between 0 and 10 micrograms per deciliter, and found that those in the 0-5 range had average IQs of about five points higher than those in the 5-10 range. The unavoidable conclusion is that even when lead poisoning is less than what the CDC deems harmful, it can still have significant negative effects on children's developing brains.
Those who are poor are at greater risk for lead poisoning, as lead is often found in the paint of old or poorly-maintained buildings. Lead poisoning has been in the news lately, because of the Mattel recall and other toy safety issues. This very morning, New York State recalled children's jewelry from stores including Michael's and Big Lots because they contained hazardous levels of lead. It is important to remember that houses are the most common source of lead-related brain damage.
The researchers involved in this study had previously published another, similar study in 2003. They found then, as they did again now, that blood-lead levels are related "inversely and significantly" to IQ. Clearly, this is a serious problem that needs to be recognized and addressed.
