Lead Contamination: An Old Foe Rises from the Ashes of the Eaton Fire - Francois Tissot

In 1965, Caltech geochemist Clair Patterson published what was, at the time, a highly controversial finding: that leaded gasoline and other products like canned food solder, paints, and insecticide were exposing Americans to dangerously high levels of lead. His work helped galvanize the environmental movement, ultimately leading to the Clean Air Act of 1970. Fifty years later, Caltech researchers, led by Francois Tissot, professor of geochemistry and Heritage Medical Research Institute Investigator, were once again at the center of investigations on environmental lead contamination when the Eaton fire devastated communities surrounding Caltech. A year on from the LA fires of 2025, Tissot will discuss Patterson's legacy and its connections to his own research group's efforts to study the presence of lead and other toxic metals in the aftermath of the fires. He will also share the impact of his findings to date—and how they can help communities prepare as fires at the wildland-urban interface grow increasingly common.

For more information about Professor Tissot's research: https://isotoparium.org

About the Series:

Since 1922, The Earnest C. Watson Lecture Series has brought Caltech's most innovative scientific research to the public. The series is named for Earnest C. Watson, a professor of physics at Caltech from 1919 until 1959. Spotlighting a small selection of the pioneering research Caltech's faculty is currently conducting, the Watson Lectures are geared toward a general audience, as part of the Institute's ongoing commitment to benefiting the local community through education and outreach.

For more information on the Watson Lecture Series: https://caltech.edu/watson

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