Polar organic chemical integrative samplers for pesticides monitoring: impacts of field exposure conditions.
This study focuses on how Polar Organic Chemical Integrative Samplers (POCIS) work in real environmental conditions. A selection of 23 polar pesticides and 8 metabolites were investigated by exposure of triplicates of integrative samplers in two rivers in France for successive 14-day periods. The pesticides and metabolites were trapped not only in Oasis HLB sorbent but also in the polyethersulfone (PES) membrane of the POCIS. The distribution of pesticides depended on the molecular structure. The use of the Performance Reference Compound (PRC) is also discussed here. The impact of some environmental parameters and exposure setup on the transfer of pesticides in POCIS sorbent was studied: river flow rate, biofouling on membranes, sampler holding design and position in the stream. Results show a significant impact of river flow velocity on PRC desorption, especially for values higher than 4 cm·s(-1). Some fouling was observed on the PES membrane which could potentially have an impact on molecule accumulation in the POCIS. Finally, the positioning of the sampler in the river did not have significant effects on pesticide accumulation, when perpendicular exposures were used (sampler positioning in front of the water flow). The POCIS with PRC correction seems to be a suitable tool for estimating time-weighted average (TWA) concentrations, for all the molecules except for one of the nine pesticides analyzed in these two French rivers.
Research Group on Water, Soil and Environment (EA 4330), University of Limoges, 123 Avenue Albert Thomas, F-87060 Limoges, France; IRSTEA, REBX Unit, 50 Avenue de Verdun, F-33612 Cestas, France. Electronic address: sophie.lissalde@unilim.fr.
Sophie
S
Lissalde
IRSTEA, REBX Unit, 50 Avenue de Verdun, F-33612 Cestas, France.
Nicolas
N
Mazzella
University of Bordeaux, CNRS, UMR 5805, EPOC-LPTC, F-33405 Talence, France.
Patrick
P
Mazellier
D004784:Environmental Monitoring / Q000295:instrumentation* / Q000379:methods; D005602:France; D009930:Organic Chemicals / Q000032:analysis; D010575:Pesticides / Q000032:analysis*; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D009930:Organic Chemicals; D010575:Pesticides; D014874:Water Pollutants, Chemical
Field exposure; POCIS; PRC; Pesticides; Sorbent-membrane partitioning