After the Palisades/Eaton January 7 Fires, a consortium of researchers from 10 universities, including UCLA, Stanford, Yale, Harvard, USC and UC Davis tested the air quality in March and April in those two areas.
Researchers discovered the presence of Chromium 6 (Cr6) in nano-particles well above the typical background concentrations for Los Angeles.
CTN spoke to Dr. Mike Kleeman one of the study authors (click here.) Kleeman, a professor of civil and environmental engineering at U.C. Davis, said scientists would perform follow-up measurements and collections in early September.
Today, those results showed that chromium-6 (Cr6 or hexavalent chromium) levels have decreased in the Palisades and Altadena and are currently back to the typical low levels detected in Los Angeles.
South Coast AQMD (click here.) found similar results with their stationary samples, also collected in September.
Measurements show that chromium-6 weathered back to its more stable and less toxic chromium-3 form over time.
In August, Kleeman said, “The theory is the ash contained the Chromium 6 that was observed during debris removal. We hope the problem is over now that debris removal is complete, but we need to check it.”
The heaviest debris removal in Pacific Palisades, according to the Army Corps of Engineers was in April, which may support Kleeman’s theory.
Scientists said that “Further investigation is still needed to determine the source of the Cr6 in earlier measurements, to help understand how to prevent more exposures in future wildfires, and to ensure that future debris removal or construction activities in the area do not cause additional exposures.”
(Editor’s note: The Los Angeles Fire Human Exposure and Long-Term Health (HEALTH) Study is a 10-year study of the LA wildfires to evaluate which pollutants are present, at what levels, and where, and to assess the respiratory, neurological, cardiovascular, reproductive, and immune system impacts of the wildfires. Learn more. (click here.)