Scientists and environmental regulators have been studying PFAS for years now, but new details are still coming out that make these so-called "forever chemicals" seem even more hazardous than previously thought.

Earlier this month, the EPA said it's unsafe to be exposed to essentially any amount of PFOA and PFOS, the two most well-known PFAS chemicals. The agency set a new non-binding health advisory for these two chemicals at less than one tenth of one part per trillion. The EPA's prior standards set in 2016 were thousands of times higher this and, furthermore, current PFAS sampling technology can only detect concentrations of four parts per trillion and above.

Bloomberg Law chemicals reporter Pat Rizzuto joined our environmental podcast to talk about why the agency took this extraordinary step, where the science on PFAS chemicals is heading, and what this will mean for regulators grappling with this ongoing environmental problem.

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