title: Development of a multichemical food web model: application to PBDEs in Lake Ellasjoen, Bear Island, Norway.
abstract: A multichemical food web model has been developed to estimate the biomagnification of interconverting chemicals in aquatic food webs. We extended a fugacity-based food web model for single chemicals to account for reversible and irreversible biotransformation among a parent chemical and transformation products, by simultaneously solving mass balance equations of the chemicals using a matrix solution. The model can be applied to any number of chemicals and organisms or taxonomic groups in a food web. The model was illustratively applied to four PBDE congeners, BDE-47, -99, -100, and -153, in the food web of Lake Ellasjøen, Bear Island, Norway. In Ellasjøen arctic char (Salvelinus alpinus), the multichemical model estimated PBDE biotransformation from higher to lower brominated congeners and improved the correspondence between estimated and measured concentrations in comparison to estimates from the single-chemical food web model. The underestimation of BDE-47, even after considering bioformation due to biotransformation of the otherthree congeners, suggests its formation from additional biotransformation pathways not considered in this application. The model estimates approximate values for congener-specific biotransformation half-lives of 5.7,0.8,1.14, and 0.45 years for BDE-47, -99, -100, and -153, respectively, in large arctic char (S. alpinus) of Lake Ellasjøen.
authors.affiliation: Division of Environmental Engineering, Department of Chemical Engineering and Applied Chemistry, University of Toronto, Toronto, ON, Canada, M5S 3E5.
authors.forename: Nilima
authors.initials: N
authors.lastname: Gandhi
authors.forename: Satyendra P
authors.initials: SP
authors.lastname: Bhavsar
authors.forename: Sarah B
authors.initials: SB
authors.lastname: Gewurtz
authors.forename: Miriam L
authors.initials: ML
authors.lastname: Diamond
authors.forename: Anita
authors.initials: A
authors.lastname: Evenset
authors.forename: Guttorm N
authors.initials: GN
authors.lastname: Christensen
authors.forename: Dennis
authors.initials: D
authors.lastname: Gregor
mesh_terms: D000818:Animals; D001711:Biotransformation / Q000502:physiology*; D020387:Food Chain; D005618:Fresh Water / Q000737:chemistry; D005843:Geography; D055768:Halogenated Diphenyl Ethers; D008954:Models, Biological; D008956:Models, Chemical; D009664:Norway; D010647:Phenyl Ethers / Q000737:chemistry* / Q000378:metabolism; D011075:Polybrominated Biphenyls / Q000737:chemistry* / Q000378:metabolism; D011078:Polychlorinated Biphenyls / Q000737:chemistry; D012680:Sensitivity and Specificity; D014337:Trout / Q000378:metabolism; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000737:chemistry
chemical_list: D055768:Halogenated Diphenyl Ethers; D010647:Phenyl Ethers; D011075:Polybrominated Biphenyls; D014874:Water Pollutants, Chemical; C086401:pentabromodiphenyl ether; D011078:Polychlorinated Biphenyls