Study of water contamination by pesticides, comparison of grab sampling and passive sampling – Application to natural water and an industrial-zone sewage near Bordeaux
One hundred and nineteen pesticides were investigated in the Aquitaine river “la Jalle d’Eysines”, and in industrial-zone sewage waters from Bordeaux in France, for two sampling campaigns. Compounds were quantified with average grab sampling and Polar Organic Chemical Integrative Samplers (POCIS) were used at these sampling points for screening purposes. Waters of the same origin had similar contamination profiles. However these profiles were different in structure and concentration between waters of different origins. The qualitative approach with passive samplers demonstrates that some compounds are not quantified in grab samples for both natural and sewage waters. POCIS seem to be interesting for pesticide analysis for the different kinds of water, provided that the targeted compounds have a log KOW value between one and four. The development of Performance Reference Compounds appears to be necessary to implement a quantitative approach based on passive sampling.