title: Mercury and methylmercury bioaccumulation by polychaete worms is governed by both feeding ecology and mercury bioavailability in coastal mudflats.
abstract: Polychaete worms are abundant in many mudflats but their importance to coastal food web Hg biomagnification is not known. We sampled sediments and polychaete worms from mudflats in the Bay of Fundy to investigate the bioaccumulation of mercury (Hg) and methylmercury (MeHg) in the coastal invertebrate food web. Hg concentrations in the sediments were low (<20 μg kg(-1)). Labile Hg (methanol/KOH sediment extraction) in surface sediments (0-1 cm) was positively correlated with Hg bioaccumulation by surface sediment-ingesting polychaetes but, surprisingly, there was a negative correlation between δ(15)N (i.e. trophic level) and THg bioaccumulation factors in polychaete worms. Worms feeding on deeper sediments contained the greatest MeHg concentrations (69.6 μg kg(-1)). Polychaetes are an important vector for Hg biomagnification to the coastal avian food web. This research demonstrates that feeding depth and method of feeding are more important than trophic position or sediment Hg concentrations for predicting Hg bioaccumulation.
authors: Department of Earth & Environmental Science, KC Irving Environmental Science Center, Acadia University, Wolfville, NS B4P 2R6, Canada.
authors: Tom
authors: T
authors: Sizmur
authors: João
authors: J
authors: Canário
authors: Travis G
authors: TG
authors: Gerwing
authors: Mark L
authors: ML
authors: Mallory
authors: Nelson J
authors: NJ
authors: O'Driscoll
mesh_terms: D000818:Animals; D004463:Ecology; D017753:Ecosystem; D004784:Environmental Monitoring; D020387:Food Chain; D019015:Geologic Sediments / Q000737:chemistry; D008628:Mercury / Q000032:analysis / Q000378:metabolism*; D008767:Methylmercury Compounds / Q000032:analysis / Q000378:metabolism*; D011077:Polychaeta / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*
chemical_list: D008767:Methylmercury Compounds; D014874:Water Pollutants, Chemical; D008628:Mercury