Prioritisation of veterinary pharmaceuticals prior to a monitoring campaign into water resources and drinking water: Case of Brittany, an intensive husbandry area

Pharmaceuticals residues are nowadays of growing concern, especially in aquatic environments. Numerous and detailed researches have been conducted on human pharmaceutical residues at national and european scale, while ocurrence of veterinary pharmaceutical residues remains still largely unknown. Brittany is a region subjected to high animal husbandry pressures. Veterinary pharmaceuticals residues can enter the environment directly or indirectly during pastures or spreading of animal manure on soils. Thus, aquatic environments in Brittany are sensitive spots, potentially contaminated by a lot of veterinary residues, such as antibiotics or antiparasitic drugs. The project aims at realizing an overview of the contamination (types molecules and levels of concentrations) of raw water resources subjected to a strong agricultural pressure, and into drinking water obtained from those resources. In order to realize a monitoring study during one year, the first step was to perform a prioritization of veterinary pharmaceuticals, to select the veterinary pharmaceuticals which are the most susceptible to reach and to be detected in the aquatic environment.