Screening of French groundwater for regulated and emerging contaminants

•Nationwide occurrence and distribution of emerging contaminants in groundwater•Groundwater are impacted by the use of antibiotics in livestock•At least one dioxin-like compound was detected in 87% of the sampling sites•Groundwater is impacted by former anthropogenic activities•How can groundwater quality be assessed when unregulated compounds are present?

Nationwide screening of 411 emerging contaminants and other regulated compounds, including parent molecules and transformation products (TPs) having various uses and origins, was done at 494 groundwater sites throughout France during two sampling campaigns in the Spring and the Fall of 2011. One hundred and eighty substances (44% of the targeted compounds) were quantified in at least one sampling point. These included pharmaceuticals, industrial products, pesticides, their transformation products and other emerging compounds. Fifty-five compounds were quantified in more than 1% of the samples. Both regulated and emerging compounds were found. Among the unregulated compounds, acetaminophen, carbamazepine, perfluorinated compounds, dioxins/furans, tolyltriazole, bisphenol A, triazine transformation products, and caffeine were quantified in more than 10% of the samples analyzed. Concentrations exceeding the threshold of toxicological concern of 0.1 μg/L were found for tolyltriazole, bisphenol A and some of the triazine transformation products (DEDIA). These new results should help the water resource managers and environmental regulators develop sound policies regarding the occurrence and distribution of regulated and emerging contaminants in groundwater.