Mohammed Athari, commenting in Megan's blog, provided a good Pb and behavior reference.

From an EPA reference ... Final volume, p. 6-45, "Cord blood Pb levels were not associated with the prevalence or nature of behavior problems reported by teachers." Though apparently a regression analysis did show a correlation between tooth Pb and the ACBP Total Problem Behavior Scores which assess both both "under- and overcontrol of behaviors. Only weak associations were seen between tooth Pb concentrations and the tendency to score in the clinically significant range on these scales." Earlier in the very extensive discussion, the reports suggests it is 'problematic' to make an association with behavior and what Pb levels we have had. OTOH, Pb seems to have affected visual-motor cortex preferentially in low doses and mildly impairs intelligence, may have been a mildly significant toxin during the early years of feminist, in pregnancy, smoking rebellion.