US Wildfire Suppressants Rife With Toxic Heavy Metals, Study Finds

A new study reveals that widely used pink wildfire suppressants contain high levels of toxic heavy metals like cadmium, arsenic, and chromium, with concentrations up to 3,000 times above drinking water limits. While the government and chemical makers have long concealed up to 20% of the suppressants' ingredients as 'trade secrets,' researchers have confirmed their role in environmental pollution, raising concerns over their extensive use in residential areas. The Guardian reports: The suppressants are a mix of water, fertilizer, and undisclosed ingredients, while the pink color comes from added dye to show firefighters where it has been sprayed. Metals are likely used as anti-corrosion agents to prevent the plane's tankers from disintegrating, they authors wrote. The mix works by coating vegetation and lowering the amount of oxygen that could fuel the fire. The substance was dropped by as many as 25 aircraft daily to contain the devastating Los Angeles wildfires, and photos from it vividly convey the trade off, showing homes and property covered in hot pink suppression.

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. 'Are the hazardous waste thresholds the appropriate bar for these to clear, or, if they're being used in a massive scale in populated neighborhoods, do we need to get stricter on permissible concentrations of toxic compounds?' McCurry asked. The producer of one of the suppressants has said a new generation of the product is 'greener,' McCurry said, but he added 'until we are able to come across some of this material and test it, we really don't know.'

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