Assessing metal bioaccumulation in aquatic environments: The inverse relationship between bioaccumulation factors, trophic transfer factors and exposure concentration
DeForest, D.K.; Brix, K.V.; Adams, W.J. (2007). Assessing metal bioaccumulation in aquatic environments: The inverse relationship between bioaccumulation factors, trophic transfer factors and exposure concentration. Aquat. Toxicol. 84(2): 236-246. https://dx.doi.org/10.1016/j.aquatox.2007.02.022 In: Aquatic Toxicology. Elsevier Science: Tokyo; New York; London; Amsterdam. ISSN 0166-445X; e-ISSN 1879-1514, more Also appears in:Wood, C.M.; Gorsuch, J.W. (Ed.) (2007). Proceedings of a Symposium: SETAC 27th Annual Meeting. A Tribute to Rick Playle: The interface of toxicology, physiology, and modeling in improving water quality regulations for metals, Montreal, Quebec, Canada, November 5-9, 2006. Aquatic Toxicology, 84(Spec. Issue 2). Elsevier: Amsterdam. 119-298, I-X pp., more | |
Keywords | Biological phenomena > Accumulation > Bioaccumulation Chemical elements > Metals Hazard assessment Risk assessment Techniques > Estimation > Assessment > Risk assessment Vulnerability assessment > Risk assessment Marine/Coastal; Brackish water; Fresh water | Author keywords | metals; bioaccumulation; trophic transfer; hazard assessment; riskassessment |
Authors | | Top | - DeForest, D.K.
- Brix, K.V.
- Adams, W.J.
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Abstract | Bioaccumulation potential in aquatic biota is typically expressed using ratios of chemical concentrations in organism tissue (typically whole body) relative to chemical exposure concentrations, such as bioconcentration factors (BCFs). Past reviews of metal BCFs for aquatic biota, which account for water-only exposures, have shown that BCFs are often highly variable between organisms and generally inversely related to exposure concentration. This paper further evaluates trends in metal bioaccumulation data by evaluating data for bioaccumulation factors (BAFs) and trophic transfer factors (TTFs). Bioaccumulation factor data were compiled from field studies that account for combined waterborne and dietary metal exposures. Trophic transfer factor data for metals were compiled from laboratory studies in which aquatic food chains were simulated. Natural aquatic food webs are rarely sufficiently understood to properly evaluate exact predator–prey relationships (i.e., TTFs). Results indicate that field BAFs, like laboratory BCFs, tend to be significantly (p ≤ 0.05) inversely related to exposure concentration. Bioaccumulation factors are frequently 100–1000 times larger than BCFs for the same metal and species. This difference is attributed to both lower exposure levels in the field and inclusion of the dietary exposure route. Trophic transfer factors for the metals reviewed, including selenium and methyl mercury were also observed to be inversely related to exposure concentration, particularly at lower exposure concentrations. These inverse relationships have important implications for environmental regulations (e.g., hazard classification and tissue residue-based water quality criteria) and for the use of metal bioaccumulation data in site-specific environmental evaluations, such as ecological and human health risk assessments. Data presented indicate that for metals and metalloids, unlike organic substances, no one BAF or TTF can be used to express bioaccumulation and/or trophic transfer without consideration of the exposure concentration. |
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