Presentation Abstract
We examine the influence of sediment factors on uptake of PBDEs into marine deposit and filter feeders, and transfer to higher trophic levels. Sediment PBDEs increase with %toc, AVS, organic flux, and fines. As a result, coarser, less organic sediments in JdF have lower [PBDEs] than the southern SoG. Sediment feeder [PBDE] variance was best explained by AVS>[PBDEs]>%TOC>OC flux. Therefore, increasing organic input and burn-down, and sediment PBDEs enhance tissue PBDEs. Dry weight PBDE accumulation (tissue/sediment) in sediment feeders decreased with increasing sediment PBDEs, resulting in tissue dilution at sediment concentrations >10,000pg/g in urban harbours. PBDE accumulation decreased with increasing fines. As a result, accumulation was higher in JdF than SoG. These patterns imply low bioavailability at high sediment PBDEs. Dry weight PBDEs increased ~107x from background benthos to predators, crabs and seal blubber, whereas lipid weight differences were 1. Thus bio-accumulation trends require understanding of food resources in higher trophic fauna. The greatest change in congenor composition occurs at sediment uptake. Dominant nona/deca- BDEs in sediments decline concurrent with increasing tetra-hexa BDEs. Sediment feeders near outfalls and in background locations had similar proportions of congenors. Harbour feeders had a composition similar to sediments. Along with the noted bio-dilution, this suggests that uptake of PBDEs is so rapid at high sediment levels that most passes un-modifed through guts. BDE-209 varies throughout the food chain, reflecting shifting dependence on sediment versus pelagic food resources. In higher trophic level fauna, debromination of penta/hexa to tetra BDEs is much slower than initial debromination of deca/nona-BDEs. Tetra-BDEs appear to be a metabolic "dead-end".
Session Title
Contaminants in Marine Mammals of the Salish Sea and Their Food Web
Keywords
PBDEs, Trophic uptake, Benthos
Conference Track
SSE3: Fate, Transport, and Toxicity of Chemicals
Conference Name
Salish Sea Ecosystem Conference (2018 : Seattle, Wash.)
Document Type
Event
SSEC Identifier
SSE3-595
Start Date
4-4-2018 1:30 PM
End Date
4-4-2018 1:45 PM
Type of Presentation
Oral
Genre/Form
presentations (communicative events)
Contributing Repository
Digital content made available by University Archives, Heritage Resources, Western Libraries, Western Washington University.
Subjects – Topical (LCSH)
Polybrominated diphenyl ethers--Salish Sea (B.C. and Wash.); Groundfishes--Nutrition--Salish Sea (B.C. and Wash.)
Geographic Coverage
Salish Sea (B.C. and Wash.)
Rights
This resource is displayed for educational purposes only and may be subject to U.S. and international copyright laws. For more information about rights or obtaining copies of this resource, please contact University Archives, Heritage Resources, Western Libraries, Western Washington University, Bellingham, WA 98225-9103, USA (360-650-7534; heritage.resources@wwu.edu) and refer to the collection name and identifier. Any materials cited must be attributed to the Salish Sea Ecosystem Conference Records, University Archives, Heritage Resources, Western Libraries, Western Washington University.
Type
Text
Language
English
Format
application/pdf
Included in
Fresh Water Studies Commons, Marine Biology Commons, Natural Resources and Conservation Commons, Terrestrial and Aquatic Ecology Commons
Uptake and trophic changes of PBDEs in the benthic marine food chain
We examine the influence of sediment factors on uptake of PBDEs into marine deposit and filter feeders, and transfer to higher trophic levels. Sediment PBDEs increase with %toc, AVS, organic flux, and fines. As a result, coarser, less organic sediments in JdF have lower [PBDEs] than the southern SoG. Sediment feeder [PBDE] variance was best explained by AVS>[PBDEs]>%TOC>OC flux. Therefore, increasing organic input and burn-down, and sediment PBDEs enhance tissue PBDEs. Dry weight PBDE accumulation (tissue/sediment) in sediment feeders decreased with increasing sediment PBDEs, resulting in tissue dilution at sediment concentrations >10,000pg/g in urban harbours. PBDE accumulation decreased with increasing fines. As a result, accumulation was higher in JdF than SoG. These patterns imply low bioavailability at high sediment PBDEs. Dry weight PBDEs increased ~107x from background benthos to predators, crabs and seal blubber, whereas lipid weight differences were 1. Thus bio-accumulation trends require understanding of food resources in higher trophic fauna. The greatest change in congenor composition occurs at sediment uptake. Dominant nona/deca- BDEs in sediments decline concurrent with increasing tetra-hexa BDEs. Sediment feeders near outfalls and in background locations had similar proportions of congenors. Harbour feeders had a composition similar to sediments. Along with the noted bio-dilution, this suggests that uptake of PBDEs is so rapid at high sediment levels that most passes un-modifed through guts. BDE-209 varies throughout the food chain, reflecting shifting dependence on sediment versus pelagic food resources. In higher trophic level fauna, debromination of penta/hexa to tetra BDEs is much slower than initial debromination of deca/nona-BDEs. Tetra-BDEs appear to be a metabolic "dead-end".
