The relationship between blood-lead concentrations, intelligence, attainment and behaviour in a school population: the second London study.

This study replicates an earlier one carried out in London in which an association was found between lead and intelligence, reading and spelling. In the present study 194 children living near an urban motorway were given the same battery of tests as well as an extensive family interview to determine background variables. Before social factors were taken into account there were no significant associations between lead and outcome variable. Possible reasons for the negative results from this study are discussed.