After U.S. Sen. Marco Rubio sidestepped a question on the age of the earth, geochemistry has enjoyed a spurt of recent media coverage. But did you know the chemist who established Earth’s age — and prevented millions of lead poisoning cases in the process — was a Grinnellian?
In 1955, Clair C. Patterson ’43 studied lead ratios in meteorites to pinpoint Earth’s age at 4.5 billion years, a figure that has held for nearly six decades and disproved the previous 3-billion-year estimate.
Patterson, who died in 1995, quickly recognized that if ancient meteorites contained traces of lead, then the Industrial Age was drowning in it. By studying pre-Iron Age mummies, he determined that lead levels in modern humans were hundreds of times higher than in their millennia-old ancestors. His findings led to congressional hearings that paved the way to remove lead from products including paint, pesticides, and gasoline.
After growing up with chemistry kits and a home lab in his parents’ Mitchellville, Iowa basement, Patterson arrived at Grinnell primed for the College laboratories’ exploratory freedom. “I could be a renegade,” he said in a 1995 interview. “I loved the fact that you could go in the laboratory and work your heart out … You could play all sorts of games.” Patterson went on to earn a Ph.D. from the University of Chicago and taught for decades in the Caltech geochemistry department. Other Grinnellians in the family include his widow, Lorna McCleary Patterson ’43; their four children; and a grandson.
