An asteroid chemist who studies LA lead levels

When raised lead levels were noticed in Los Angeles last year, Professor Francois Tissot, who usually examines the chemistry of asteroids, quickly saw that the fires that ravaged the region in January 2025 were to blame. He reveals the current extent of the concern and suggests Australia inspects its own burned regions too. Guest Francois Tissot Professor of geochemistry Caltech PresenterRobyn Williams