Transformation products of emerging organic compounds as future groundwater and drinking water contaminants

Nanogram per litre concentrations of a wide range of emerging contaminants are currently being detected in groundwater as well as their metabolites and transformation products. In some cases transformation products are found at concentrations equalling or exceeding those of the parent compounds. These come from both point and diffuse sources and may enter the subsurface directly or through groundwater/surface water interaction. Geochemical conditions in the subsurface favourable to persistence and long water residence times mean that these compounds may pose a threat to the environment or to drinking water abstractions for decades to come.