Santa Rosa fires likely created new and dangerous chemical compounds
As fires worked their way through suburban subdivisions in Santa Rosa, California last year, they may have done more than destroy lives and property. By incinerating a plethora of material — insulation, electronics, furniture, cleaning products, pesticides — at very high temperatures, they likely created unknown or previously unrecognized health hazards in the air, land and waterways.
The makeup of the ash and other particulates left by the fires depends on the age
of the burned homes and office buildings. Those built before 1980, for example, will usually have lead in the paint. And more modern pressure-treated wood used in landscaping and back-yard gardens are full of a chemical called chromate copper arsenate, which releases arsenic and hexavalent chromium into the environment. This can be very bad for fish and other living things. Copper and Zinc are also found in building materials and mercury vapors escape from every broken fluorescent bulb. Common household electronics often contain compounds that can be hazardous when inhaled, absorbed through the skin or ingested.
According to Tom Young, professor in the Department of Civil and Environmental Engineering at UC Davis, the health hazards that the left over compounds pose are not yet known.
“Conventional assessments rely on things that we already know are pollutants, such as industrial chemicals,” Young said. “But we don’t know what new chemicals might have been created from combustion” of all these materials.
In addition, researcher Keith Bein and colleagues from the UC Davis Air Quality Research Center plan to regularly collect air samples from these sites as the area recovers from the fires. While they were still burning, Bein’s team collected samples of smoky air in the Bay Area and Davis. But for years to come, they expect, dust in the burned sections will contain particles of fire ash. The researchers will look specifically at airborne particles less than 2.5 microns in size that can penetrate deep into the lungs.
“This was a very unique type of fire, an urban wildfire,” Bein said. “We know what wildfire smoke is composed of, but we have no idea what will be in this — we expect it to be very different.”
They plan to begin monthly sampling in the Sonoma and Napa areas this spring. In future, Bein hopes that the mobile unit can be deployed quickly into an affected area.