Rice fields regulate organochlorine pesticides and PCBs in lagoons of the Nature Reserve of Camargue.
In order to assess pollutant transfer in Camargue ponds from bordering agrosystems, a biomonitoring assay was conducted in irrigation and drainage channels of rice fields in the Rhone Delta (France). A filter-feeding bivalve, the Asian clam, Corbicula fluminea, was used as bioindicator and caged in upstream and downstream channels of an area of conventional rice fields. After 6 weeks incubation, many lipophilic biocides were identified in Corbicula tissues, including pesticides used in rice plantations (pretilachlor, oxadiazon), pesticides presumed in use in the Rhone basin [diuron and its metabolite 3,4 dichloroaniline (3,4-DCA)] and organochlorine pesticides (OCPs) banned for several decades. In addition, PCBs were highly bioaccumulated in Corbicula. Downstream bivalves had significantly lower concentrations of OCPs, PCB and 3,4-DCA. However, the exposure biomarkers (glutathione S-transferase, catalase and propionylcholinesterase) were not correlated with the decreased concentrations. The results of this experiment raise several questions concerning the potential role of immersed plants in a retention process.
Roche
H
H
Ecologie Systématique et Evolution, UMR8079 CNRS, Univ. Paris-Sud, AgroParisTech, F91405 Orsay Cedex, France. helene.roche@u-psud.fr
Vollaire
Y
Y
Martin
E
E
Rouer
C
C
Coulet
E
E
Grillas
P
P
Banas
D
D
D000383:Agriculture; D000814:Aniline Compounds / Q000032:analysis; D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D002802:Cholinesterases / Q000378:metabolism; D049874:Corbicula / Q000378:metabolism*; D004784:Environmental Monitoring / Q000379:methods; D005982:Glutathione Transferase / Q000378:metabolism; D006843:Hydrocarbons, Chlorinated / Q000032:analysis*; D012275:Oryza; D010573:Pesticide Residues / Q000032:analysis*; D010575:Pesticides / Q000032:analysis*; D011078:Polychlorinated Biphenyls / Q000032:analysis*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D000814:Aniline Compounds; D015415:Biomarkers; D006843:Hydrocarbons, Chlorinated; D010573:Pesticide Residues; D010575:Pesticides; D014874:Water Pollutants, Chemical; C014464:3,4-dichloroaniline; D011078:Polychlorinated Biphenyls; D002374:Catalase; D005982:Glutathione Transferase; C025181:propionylcholinesterase; D002802:Cholinesterases