About half of California waterways contaminated with Pfas, pesticide analysis finds

Crop field being irrigated near Kern county’s Bakersfield, California, on 22 October 2021. Photograph: Citizens of the Planet/UCG/Universal Images Group/Getty Images View image in fullscreen Crop field being irrigated near Kern county’s Bakersfield, California, on 22 October 2021. Photograph: Citizens of the Planet/UCG/Universal Images Group/Getty Images About half of California waterways contaminated with Pfas, pesticide analysis finds Review detects ‘forever chemicals’ in many of the state’s tested streams and rivers, including drinking water sources Around half of California waterways tested by regulators are contaminated with pesticides considered Pfas , “forever chemicals”, a new analysis of state and federal records shows, highlighting a risk in the substances’ wide use that is only beginning to come into focus. The pesticides are linked to a range of health problems, including cancer, and the review is the first to systematically check for the dangerous substances in streams and rivers, which include drinking water sources. More than half of sediment samples also showed some levels of the pesticides, which are increasingly applied to California and the nation’s food crops. The review of California department of pesticide regulation and United States geological survey data was released this week, just days before a proposal to eventually ban Pfas pesticides failed to make it through the state assembly. However, pieces of the legislation, including a moratorium on approvals of the new pesticides, passed. The findings are “alarming but not surprising”, said Varun Subramaniam, one of the report’s co-authors with the Environmental Working Group (EWG) non-profit. “It’s concerning that we’re finding these levels of Pfas pesticide … but they were applied at really high rates on produce, so it makes sense that they’re in the streams and sediment,” he said. Pfas are a class of at least 16,000 compounds most frequently used to make products water-, stain- and grease-resistant. They have been linked to cancer, birth defects, decreased immunity, high cholesterol, kidney disease and a range of other serious health problems. They are dubbed “forever chemicals” because they can persist for thousands of years in the environment, and are designed to be indestructible. The chemicals are added as an active ingredient to food crop pesticides to kill weeds or insects, or used as an inert ingredient. At least 60% of active ingredients in pesticides fit the most widely accepted definition of Pfas, a 2023 analysis of EPA data found. California farms applied an average of 2.5m lb of Pfas per year on cropland from 2018 to 2023, a review of state records last year revealed. Recent regulatory testing found the pesticide residues on 37% of all produce. But about 90% of peaches, plums and nectarines contained Pfas, while 80% of strawberries and grapes showed them. Public health advocates have said the pesticides almost certainly pollute nearby water sources, and the new