Do low levels of lead produce IQ loss in children? A careful examination of the literature

Three meta-analyses on the relationship of low levels of lead to loss of IQ points in children, which included a total of 26 well-controlled studies, provided the raw materials for the analysis presented here. Despite some ke y limitations, results of lead-IQ studies have been instrumental in setting public policy. In this paper, five shortcomings in these studies are addre ssed, which, when taken together, suggest greater caution in the interpreta tion of the lead-IQ data. In addition, some other issues are addressed conc erning the IQ loss attributed to low levels of lead. (C) 2001 National Acad emy of Neuropsychology. Published by Elsevier Science Ltd.