Lead Pollution Evidence in Ice Cores

The world’s

history of lead pollution is neatly recorded in a 450-foot (135-meter) ice core drilled in Greenland, representing almost 250 years of accumulation. According to a study to be published in an upcoming issue of

Geophysical Research Letters, lead emissions skyrocketed in 1870 and climbed 300% by 1890. After a drop during the 1930s’ Depression, lead levels climbed again following World War II and the addition of lead to gasoline. The phaseout of leaded gasoline brought lead levels down 75% from the all-time peak that occurred during the mid-1970s.