A Century of Hair Samples Proves Leaded Gas Ban Worked

Scientists at the University of Utah have analyzed nearly a century's worth of human hair samples and found that lead concentrations dropped 100-fold after the EPA began cracking down on leaded gasoline and other lead-based products in the 1970s. The findings, published in the Proceedings of the National Academy of Sciences, drew on hair collected from Utah residents - some preserved in family scrapbooks going back generations. Lead levels peaked between 1916 and 1969 at around 100 parts per...