A century of hair clippings show lead exposure rates have plummeted

Scientific American sought the expertise of Katarzyna Kordas for an article about recent research that analyzed hair samples from the 1960s onward to assess lead exposure levels. “We have this notion that we need large studies to be able to show trends, and this study is indicating that we can still in a small group of people see things that are remarkably clear,” said Kordas, who was not involved in the research. She noted that much of the best research on lead levels has used blood samples to gauge exposure, and the studies date only to the later decades of the 20th century. “As a toxin goes, lead is serious, and we should certainly be concerned and striving to lower population exposure,” she said. “I don’t think that we can let our guards down and say, ‘This is a solved issue.’”