A quick look at Blood Lead Concentrations Less than 10 Micrograms per Deciliter and Child Intelligence at 6 Years of Age by Todd A. Jusko, Charles R. Henderson, Jr., Bruce P. Lanphear et al., published online in Environmental Health Perspectives.
The current CDC definition of elevated blood lead in a child is 10 micrograms of lead per deciliter of blood (written as 10 μg/dL). However, there is increasingly compelling evidence that lower blood lead levels are associated with decreased performance on intelligence testing. At the same time, it has just been reported that the EPA has just rejected the advice of scientific staff and an advisory committee to strengthen its environmental lead exposure standard, because of the deleterious effects of low level lead exposure. The study is still more evidence that lead remains a threat to children, even at levels previously thought to be safe, and that a stronger standard is needed.
(Read more from David Mich aels on the pumphandle)