title: Bottom trawling resuspends sediment and releases bioavailable contaminants in a polluted fjord.
abstract: Sediments are sinks for contaminants in the world's oceans. At the same time, commercial bottom trawling is estimated to affect around 15 million km(2) of the world's seafloor every year. However, few studies have investigated whether this disturbance remobilises sediment-associated contaminants and, if so, whether these are bioavailable to aquatic organisms. This field study in a trawled contaminated Norwegian fjord showed that a single 1.8 km long trawl pass created a 3-5 million m(3) sediment plume containing around 9 t contaminated sediment; ie. 200 g dw m(-2) trawled, equivalent to c. 10% of the annual gross sedimentation rate. Substantial amounts of PCDD/Fs and non-ortho PCBs were released from the sediments, likely causing a semi-permanent contaminated sediment suspension in the bottom waters. PCDD/Fs from the sediments were also taken up by mussels which, during one month, accumulated them to levels above the EU maximum advised concentration for human consumption.
authors: Department of Systems Ecology, Stockholm University, S-10691 Stockholm, Sweden. clare@ecology.su.se
authors: C
authors: C
authors: Bradshaw
authors: I
authors: I
authors: Tjensvoll
authors: M
authors: M
authors: Sköld
authors: I J
authors: IJ
authors: Allan
authors: J
authors: J
authors: Molvaer
authors: J
authors: J
authors: Magnusson
authors: K
authors: K
authors: Naes
authors: H C
authors: HC
authors: Nilsson
mesh_terms: D000818:Animals; D001572:Benzofurans / Q000032:analysis / Q000378:metabolism; D049872:Bivalvia / Q000378:metabolism; D000072338:Dibenzofurans, Polychlorinated; D004784:Environmental Monitoring; D005398:Fisheries / Q000295:instrumentation / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry*; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000378:metabolism; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives / Q000032:analysis / Q000378:metabolism; D013548:Sweden; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
chemical_list: D001572:Benzofurans; D000072338:Dibenzofurans, Polychlorinated; D000072317:Polychlorinated Dibenzodioxins; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls