The United States has made extraordinary progress during the past 50 years in reducing children’s exposure to lead. In the early 1970s, lead was ubiquitous in the US environment.1 It was marketed aggressively by the lead industry2 (Figure 1) and was used in paint, water pipes, and plumbing fixtures. More than 100 000 tons of tetraethyl lead were added each year to gasoline to improve automotive engine performance, and lead contamination of air, soil, and dust in urban centers and along highways was extensive.3 Scientists employed by the lead industry claimed that lead was an essential trace element, necessary for children’s nutrition.4