Researchers detected high levels of heavy metals in fire suppressants, suggesting an explanation for why concentrations of the toxic elements in the environment spike after wildfires.
The dust clouds of long-term fire retardants released by planes to control wildfires contain concentrations of heavy metals up to 2,880 times greater than EPA’s drinking water regulatory limits, according to a study published Wednesday in the peer-reviewed journal Environment Science & Technology Letters.
The study’s authors, engineers at the University of Southern California, found each of the 14 fire suppression products contained at least eight of the 10 heavy metals tested — vanadium, chromium, manganese, copper, arsenic, cadmium, antimony, barium, thallium and lead.
Long-term fire retardants, mixtures of salts or fertilizers primarily used by the Forest Service to fight wildfires, contained concentrations far greater than their gel or foam counterparts, more often used in homes.
