TY - JOUR T1 - Risk assessment of herbicides and booster biocides along estuarine continuums in the Bay of Vilaine area (Brittany, France) A1 - Caquet,Th. A1 - Roucaute,M. A1 - Mazzella,N. A1 - Delmas,F. A1 - Madigou,C. A1 - Farcy,E. A1 - Burgeot,Thierry A1 - Allenou,Jean-Pierre A1 - Gabellec,Raoul AD - INRA, Ecol & Sante Ecosyst UMR985, Equipe Ecotoxicol & Qualite Milieux Aquat, F-35042 Rennes, France. AD - IRSTEA, UR REBX, F-33612 Cestas, France. AD - IFREMER, Unite Biogeochim & Ecotoxicol, F-44311 Nantes, France. AD - IFREMER, Lab Cotier Morbihan Pays Loire, F-56470 La Trinite Sur Mer, France. UR - https://doi.org/10.1007/s11356-012-1171-y DO - 10.1007/s11356-012-1171-y KW - Estuary KW - Herbicides KW - Booster biocides KW - Species sensitivity distribution KW - Risk quotient KW - AtlanticCoast N2 - A 2-year study was implemented to characterize the contamination of estuarine continuums in the Bay of Vilaine area (NW Atlantic Coast, Southern Brittany, France) by 30 pesticide and biocide active substances and metabolites. Among these, 11 triazines (ametryn, atrazine, desethylatrazine, desethylterbuthylazine, desisopropyl atrazine, Irgarol 1051, prometryn, propazine, simazine, terbuthylazine, and terbutryn), 10 phenylureas (chlortoluron, diuron, 1-(3,4-dichlorophenyl)-3-methylurea, fenuron, isoproturon, 1-(4-isopropylphenyl)-3-methylurea, 1-(4-isopropylphenyl)-urea, linuron, metoxuron, and monuron), and 4 chloroacetanilides (acetochlor, alachlor, metolachlor, and metazachlor) were detected at least once. The objectives were to assess the corresponding risk for aquatic primary producers and to provide exposure information for connected studies on the responses of biological parameters in invertebrate sentinel species. The risk associated with contaminants was assessed using risk quotients based on the comparison of measured concentrations with original species sensitivity distribution-derived hazardous concentration values. For EU Water Framework Directive priority substances, results of monitoring were also compared with regulatory Environmental Quality Standards. The highest residue concentrations and risks for primary producers were recorded for diuron and Irgarol 1051 in Arzal reservoir, close to a marina. Diuron was present during almost the all survey periods, whereas Irgarol 1051 exhibited a clear seasonal pattern, with highest concentrations recorded in June and July. These results suggest that the use of antifouling biocides is responsible for a major part of the contamination of the lower part of the Vilaine River course for Irgarol 1051. For diuron, agricultural sources may also be involved. The presence of isoproturon and chloroacetanilide herbicides on some dates indicated a significant contribution of the use of plant protection products in agriculture to the contamination of Vilaine River. Concentration levels and associated risk were always lower in estuarine sites than in the reservoir, suggesting that Arzal dam reduces downstream transfer of contaminants and favors their degradation in the freshwater part of the estuary. Results of the additional monitoring of two tidal streams located downstream of Arzal dam suggested that, although some compounds may be transferred to the estuary, their impact was probably very low. Dilution by marine water associated with tidal current was also a major factor of concentration reduction. It is concluded that the highest risks associated to herbicides and booster biocides concerned the freshwater part of the estuary and that its brackish/saltwater part was exposed to a moderate risk, although some substances may sometimes exhibit high concentration but mainly at low tide and on an irregular basis. Y1 - 2013/02 PB - Springer Heidelberg JF - Environmental Science And Pollution Research SN - 0944-1344 VL - 20 IS - 2 SP - 651 EP - 666 ID - 23571 ER -