Ecological risk assessment of persistent toxic substances for the clam Tapes philipinarum in the Lagoon of Venice, Italy.
Because of contamination of sediments of the Lagoon of Venice, Italy, by inorganic pollutants (e.g., arsenic, cadmium, chromium, copper, lead, mercury, nickel, and zinc) and organic pollutants (e.g., polychlorobiphenyls), as well as the ecological and economical relevance of the edible clam Tapes philipinarum, an ecological risk assessment was undertaken to ascertain the extent of bioaccumulation that would pose a significant risk. Risk was estimated by means of toxic units and hazard quotient approaches, by comparing the exposure concentration with the effect concentration. Clam exposure was estimated by applying previous results based on bioaccumulation spatial regression models. In addition, a comparison was made between sum of dioxin-like polychlorinated biphenyl (PCB) congeners and total PCB bioaccumulation provided by spatial regression models and by a partitioning model. The effect concentrations were calculated as tissue screening concentrations, as the product of pollutant sediment quality criteria and the bioaccumulation factor. Finally, the cumulative risk posed by selected inorganic pollutants and total PCBs was estimated and a map of risk was drawn. The resulting chemicals of potential ecological concern were mercury, cadmium, arsenic, and nickel, as well as, to a lesser extent, total PCBs.
Micheletti
Christian
C
Department of Environmental Sciences, University of Venice, Calle Larga S. Marta 2137, I-30123 Venice, Italy.
Critto
Andrea
A
Carlon
Claudio
C
Marcomini
Antonio
A
D000818:Animals; D049872:Bivalvia; D004781:Environmental Exposure; D019015:Geologic Sediments / Q000737:chemistry*; D007558:Italy; D019216:Metals, Heavy / Q000032:analysis / Q000493:pharmacokinetics*; D008962:Models, Theoretical; D009930:Organic Chemicals; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000493:pharmacokinetics*; D018570:Risk Assessment; D014018:Tissue Distribution; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000493:pharmacokinetics*
D019216:Metals, Heavy; D009930:Organic Chemicals; D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls