Research on the health impacts of wildfire smoke in areas where fire-suppression chemicals and pesticides are used is lacking, according to a recently published review by UC Davis graduate students.
The review published in the international scientific journal “Current Topics in Toxicology” found most studies on wildfire smoke focus on a limited number of chemicals and particles rather than focusing on the interaction between several components in the smoke.
“When forests and farmlands catch fire, the chemicals applied to them burn, too, and potentially travel much longer distances than where they were first used,” review author and UC Davis graduate student Sarah Carratt said in a statement. “As areas at-risk for wildfires and where pesticides are applied overlap with areas where people live and breathe, it becomes increasingly important to characterize the content of wildfire smoke.”
The study includes a map of the state overlaying areas of increased wildfire risk and areas where pesticides have been used. Humboldt County has several areas of overlap, according to the map.
UC Davis pulmonary, critical care and sleep medicine professor Jarold Last was one of the instructors of the graduate students’ summer class that would eventually result to the review’s creation.
“We know wildfire smoke is made up of small particles, gases and vapor and that it is more toxic than other smoke, but we don’t know what makes it so toxic,” Last, who is the review’s senior author, said in statement. “It’s possible that what distinguishes it are the chemicals humans add to the environment, but researchers haven’t paid enough attention to this yet.”
The review found that wildfires have been increasing nationwide, with 82 percent of the U.S. wildfires occurring in California in 2016. The greatest increase in wildfires throughout the planet has occurred in Northern California, according to the review.
The study found that the amount of flame retardant used in California increases from about 3 million gallons to 7 million gallons between 2012 and 2015. In the same time frame, the amount of pesticides used in California increased from 186 millions pounds to 194 million pounds, the study states.
While the review states it recognizes the necessary uses of fire suppression chemicals and pesticides, it states that these chemicals may need more restrictions or oversight.
“Ultimately, the benefits of applying these chemicals must be weighed against their drawbacks in order to protect the public from the immediate threat of fire while minimizing exposure to compounds with unknown human health effects,” the review states.
Will Houston can be reached at 707-441-0504.