The US federal government and chemical makers have long concealed the contents of pink wildfire suppressants widely spread by firefighting aircraft to contain blazes, but new test results provide alarming answers – the substances are rife with cadmium, arsenic, chromium and other toxic heavy metals.
The suppressants are a “major” source of toxic pollution that causes heavy-metal levels to spike in the environment, and the products themselves contain metal levels up to 3,000 times above drinking water limits, the peer-reviewed research found.
The metal levels in the suppressants meet federal guidelines and the authors were initially most worried about environmental contamination, but the heavy use in residential areas this year raises a new set of concerns, Daniel McCurry, one of the study’s co-authors, told the Guardian.
The USC researchers started with two pieces of “circumstantial evidence” that pointed to the possibility – an internal federal report that detailed metal use, and a state of Washington environmental violation notice that revealed the potential for toxic metal pollution.
“As rates of aerial fire retardant application have grown, likely so too have loadings of toxic metals released into the environment from their use, a trend which may intensify if wildfire frequency and intensity continues to increase,” the University of Southern California authors wrote.
