Study Finds Carcinogenic Chromium-6 Near Eaton and Palisades Fire Cleanup Zones

Multiple outlets reported on a new UC study finding airborne hexavalent chromium, or chromium-6, near the Eaton and Palisades Fire cleanup zones after the fires. Chromium-6 is a carcinogen linked to serious respiratory and cancer risks. Researchers found it in ultrafine nanoparticles capable of traveling deep into the lungs and potentially into the bloodstream. Initial air samples testing positive were from March 2025 during debris cleanup, with average levels below OSHA workplace limits but above EPA long-term screening levels for indoor home environments; in the months that followed, chromium-6 was no longer detected. The study estimated particles may have traveled six to nine miles downwind, potentially exposing more than 3 million people across Los Angeles County. However, other researchers cautioned that because no indoor testing was conducted, the study does not prove what harm, if any, occurred to human health. Dr. Nicole Maccalla, a data scientist who co-leads EFRU, said the findings underscore the need to prioritize health and safety over speed in fire recovery.

Action: Residents living near cleanup zones should continue using practical exposure-reduction steps when dust is active on windy days or when nearby lots have active construction in case contamination was never fully remediated. This should include indoor air filtration with activated carbon filters and avoid unnecessary outdoor activity near active debris or soil disturbance.
Read coverage from CBS News, ABC7, Pasadena Now, and LAist.