State, CDFA labs validate three new drinking‑water tests for cyanotoxins, benzotriazoles and TFA

California regulators on Nov. 4 announced three laboratory methods for contaminants of emerging concern in drinking water and described multilaboratory validation that officials said makes the tests suitable for routine monitoring. The Division of Drinking Water outlined methods developed in collaboration with the California Department of Food and Agriculture Center for Analytical Chemistry (CAC) for saxitoxins, 1H‑benzotriazole and trifluoroacetic acid (TFA), and CAC staff described single‑lab and interlab validation results.

The methods use a range of common laboratory techniques: saxitoxin testing uses an ELISA kit for rapid, low‑cost screening; benzotriazoles are measured by liquid chromatography‑tandem mass spectrometry (LC‑MS/MS) with direct injection; and TFA — a highly mobile breakdown product that can arise from PFAS and other precursors — was analyzed by LC‑MS/MS with PFAS‑aware instrument practices. CAC senior…