Arsenic and Lead Levels Higher Than Usual in Some Soil Post-Fire

By Laurel Busby

News & Information Editor

Arsenic was found at higher than usual levels in certain “hotspots” in and downwind of the Jan. 7 Palisades fire, according to testing by Roux, an environmental firm hired by L.A. County Department of Public Health.

To a lesser extent, lead, cadmium, cobalt, and thallium also exceeded the levels normally found in Southern California soil on certain parcels, while some other heavy metals or polyaromatic hydrocarbons (PAHs), including mercury, dioxin, and antimony, were at normal levels, according to Roux’s report.  

Roux tested 413 parcels in and around the Palisades, including 131 properties outside the fire boundary, 153 undamaged structures within the fire zone, and 129 properties that suffered minor damage within the fire zone, according to the company’s report.

“Widespread contamination from potentially fire-related chemicals are not evident,” the report stated. In addition, “sampling identified soil samples from isolated areas with heavy metal and PAH concentrations above screening levels.”

The screening levels are based on the typical level of a metal or PAH in local soil.

Arsenic, in particular, had the highest presence, exceeding Roux’s estimated natural occurrence in 25.6 percent of properties outside the fire boundary and around 10 percent within the fire zone. In addition, lead exceeded natural levels in 8.9 percent of the properties outside the fire zone and around 5.5 percent of tested properties within the fire zone. Cobalt also exceeded natural levels outside the fire boundary in 3.9 percent of samples showing excess amounts.

(The Canyon News approach to coverage of environmental issues can be found here.)