EPA Report: Pesticide Products Test Negative for PFAS

EPA has released a summary of its findings from a test of 10 pesticide products that reportedly contained PFAS.  While a previous study in the Journal of Hazardous Materials detected PFAS in over half of these pesticide products, EPA’s laboratory concluded that PFAS substances were not present.

EPA’s study employed two different testing methods.  The first method was the same method used in the previous study, and the second was a newly developed testing method specifically designed to detect the presence of PFAS in pesticide products formulated with surfactants.  According to the Agency, one of the most important differences between the testing methods is that the new testing method eliminates interference from oils and surfactants which can sometimes result in false positive detections.

The previous study discovered PFOS in six of the 10 tested pesticides, which are all insecticides commonly used to treat cotton.  Non-targeted techniques suggested that additional PFAS species were present in seven of the 10.  However, despite testing the same samples tested in the previous study, EPA’s study did not find evidence of PFOS or 28 other types of PFAS above the testing instrument’s background levels.

EPA writes that concern over PFAS contamination in pesticides arose in 2020, when the Agency learned of potential contamination in “a small number of mosquitocide products.”  In 2021, EPA preliminarily determined that the PFAS in those products were most likely formed during their containers’ fluorination process.  In 2022, EPA notified the fluorinated container industry of this concern and later released a study evidencing that PFAS can leach into pesticide products through these plastics.  More information on that study can be found in a previous Verdant Law blog post.