[Occurrence and Health Risk Assessment of Multiple Pesticides in Drinking Water Sources of Southeast China]

To elucidate the pollution characteristics and ecological risks of pesticide micro-pollutants in typical drinking water sources in Southeast China, the detection frequency, detection concentration, and risk quotient of each pesticide for three different trophic levels of organisms (green algae, daphnia, and fish) were analyzed for a total of 55 commonly used pesticides in 19 categories, including benzimidazoles, amides, triazoles, and organophosphates, in seven reservoirs in Southeast China. Among the 55 pesticides analyzed, two pesticides (carbendazim and acetochlor) had a detection frequency of 100%, and 12 pesticides had a detection frequency of 80% or more. The highest detection concentration was found for carbendazim (77.7 ng·L^-1), followed by that of acetochlor (51.6 ng·L^-1). The results of the risk assessment showed that most of the pesticides were at low risk in the target areas. For the three organisms, acetochlor was the risk-dominant pesticide for green algae, whereas carbendazim was the risk-dominant pesticide for fish and daphnia.