title: Consistency in trophic magnification factors of cyclic methyl siloxanes in pelagic freshwater food webs leading to brown trout.
abstract: Cyclic volatile methyl siloxanes (cVMS) concentrations were analyzed in the pelagic food web of two Norwegian lakes (Mjøsa, Randsfjorden), and in brown trout (Salmo trutta) and Arctic char (Salvelinus alpinus) collected in a reference lake (Femunden), in 2012. Lakes receiving discharge from wastewater treatment plants (Mjøsa and Randsfjorden) had cVMS concentrations in trout that were up to 2 orders of magnitude higher than those in Femunden, where most samples were close to the limit of quantification (LOQ). Food web biomagnification of cVMS in Mjøsa and Randsfjorden was quantified by estimation of trophic magnification factors (TMFs). TMF for legacy persistent organic pollutants (POPs) were analyzed for comparison. Both decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) biomagnified with TMFs of 2.9 (2.1-4.0) and 2.3 (1.8-3.0), respectively. Octamethylcyclotetrasiloxane (D4) was below the LOQ in the majority of samples and had substantially lower biomagnification than for D5 and D6. The cVMS TMFs did not differ between the lakes, whereas the legacy POP TMFs were higher in Mjøsa than inRandsfjorden. Whitefish had lower cVMS bioaccumulation compared to legacy POPs, and affected the TMF significance for cVMS, but not for POPs. TMFs of D5 and legacy contaminants in Lake Mjøsa were consistent with those previously measured in Mjøsa.
authors.affiliation: Norwegian Institute for Water Research (NIVA), Gaustadallèen 21, N-0349 Oslo, Norway.
authors.forename: Katrine
authors.initials: K
authors.lastname: Borgå
authors.forename: Eirik
authors.initials: E
authors.lastname: Fjeld
authors.forename: Amelie
authors.initials: A
authors.lastname: Kierkegaard
authors.forename: Michael S
authors.initials: MS
authors.lastname: McLachlan
mesh_terms: D000818:Animals; D002247:Carbon Isotopes; D004032:Diet; D004784:Environmental Monitoring; D020387:Food Chain; D005618:Fresh Water / Q000737:chemistry*; D060106:Lakes / Q000737:chemistry; D057230:Limit of Detection; D008055:Lipids / Q000032:analysis; D009587:Nitrogen Isotopes; D009664:Norway; D015203:Reproducibility of Results; D012833:Siloxanes / Q000032:analysis*; D014337:Trout / Q000502:physiology*; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D002247:Carbon Isotopes; D008055:Lipids; D009587:Nitrogen Isotopes; D012833:Siloxanes; D014874:Water Pollutants, Chemical; C114768:decamethylcyclopentasiloxane; C024064:octamethylcyclotetrasiloxane; C542115:dodecamethylcyclohexasiloxane