Bioaccumulation assessment

Dimitrov, S.D., Escher, B.I., Han, X. and Kramer, M.I. (2009) Bioaccumulation assessment using predictive approaches. Integr Environ Assess Manage, 5, 577-597. 

James, M., Moore, M., Plotzke, K., Segner, H., Schultz, I., Thomas, K., Vasiluk, L. and Weisbrod, A. (2007) Use of in vitro Absorption, Distribution, Metabolism, and Excretion (ADME) data in bioaccumulation assessments for fish. Human Ecol Risk Assess, 13, 1164-1191. 

Fig. 15-8 The mercury cycle, demonstrating the bioaccumulation of mercury in fish and shellfish. Reprinted with permission from An Assessment of Mercury in the Environment" (1978) by the National Academy of Sciences, National Academy Press, Washington, DC.

The sheer complexity of environmental mixtnres of EDCs, possible interactive effects, and capacity of some EDCs to bioaccumulate (e.g., in fish, steroidal estrogens and alkylphenolic chemicals have been shown to be concentrated up to 40,000-fold in the bile [Larsson et al. 1999 Gibson et al. 2005]) raises questions about the adequacy of the risk assessment process and safety margins established for EDCs. There is little question that considerable further work is needed to generate a realistic pictnre of the mixture effects and exposure threats of EDCs to wildlife populations than has been derived from studies on individual EDCs. Further discussion of the toxicity of mixtures will be found in Chapter 2, Section 2.6. 

To assess bioaccumulation in the environment, the levels of trichloroethylene in the tissues of a wide range of organisms were determined (Pearson and McConnell 1975). Species were chosen to represent several trophic levels in the marine environment. The maximum overall increase in concentration between sea water and the tissues of animals at the top of food chains, such as fish liver, sea bird eggs, and sea seal blubber, was less... 

In terms of environmental metrics to assess processes, it is hopefully clear that a considerable testing burden exists to assess potential environmental hazards that lead to a credible risk assessment. At a first pass, one would typically screen compounds from an environmental hazard perspective to assess their tendency for persistence, bioaccumulation and toxicity. Depending on the final application of the compoimd, one might avoid commercial production of a particular compound, or one might devise processes that would use the... 

Fourteen formulations of chemical alternatives were submitted to EPA under confidentiality and they were assessed based on numerous human health and ecotoxicity endpoints in addition to bioaccumulation potential and environmental persistence. They were also screened for potential exposure to workers, users and the aquatic environment. Where data gaps existed, EPA experts used models and chemical analogs to estimate the hazard for a particular endpoint. The literature and test data reviews were published in the final report, Environmentally Preferable Options for Furniture Fire Safety Low Density Furniture Foam . In addition, each hazard endpoint was ranked with a concern level (High, Moderate or Low) based on the criteria used by the EPA s New Chemicals Program to rate the concern level of new chemicals submitted under the Toxic Substance Control Act (TSCA). As seen in Figure 8.2, where the hazard endpoint rankings are bold, the value is based on experimental data. Where the hazard endpoints are presented in italic font, the value is estimated based on models or chemical analogs. In this way, detailed hazard information was summarized and presented in a clear and concise format. 

The European Commission (EC) has sponsored four reports that evaluate a set of 553 substances selected by experts and stakeholders for assessment for endocrine disruption. Each report addresses a subset of the total set based on priorities such as whether the chemicals are persistent, bioaccumulating or High Production Volume chemicals and/or whether or not there is already regulatory control of the chemical. 

Policy makers would benefit from a combination of strong field evidence of trends and well-established models to draw upon when assessing the benefits of past or future policy decisions. Models of mercury cycling and bioaccumulation are not yet adequately predictive across a range of conditions and landscapes. Results from a national mercury monitoring program, if carefully designed, offer the potential to... 

Historical data on the indicator. Existing information on the statistical variation, bias, and other interpretational attributes of potential biological indicators should be examined and considered in the design of a sampling program for assessing trends in mercury bioaccumulation. 

The criteria listed in Section 4.3.1 were applied to the selection of biological indicators to ensure their relevance and utility for assessing trends in the bioaccumulation of MeHg associated with altered loadings of mercmy to aquatic systems. This evaluation, based largely on the discussion in Section 4.3.2, is summarized in Table 4.1. 

Peech Cherewyk K. 2002. Methyhnercury bioaccumulation in zooplankton an assessment of exposure routes and accumulation in newly flooded reservoirs. MS thesis. University of Manitoba, Winnipeg, Canada, 90 p. 

Baron LA, Ashwood TL, Sample BE, Welsh C. 1997. Monitoring bioaccumulation of contaminants in the belted kingfisher (Ceryle alcyon). Environ Monit Assess 47 153-165. 

Food Chain Bioaccumulation. Bioconcentration of diisopropyl methylphosphonate occurs primarily in the leaves of plants (O Donovan and Woodward 1977a, 1977b). However, DIMP also bioconcentrates in the edible root portions of radishes and carrots, and in the fruit of tomato plants at lower levels. Exposure may occur through the ingestion of fruits and vegetables that have been irrigated with DIMP contaminated water. Additional studies are needed to assess the potential for bioconcentration in plants. While it is possible that diisopropyl methylphosphonate may enter the food chain via animal feed, DIMP is rapidly changed to IMPA by animals that eat it. Therefore, it is unlikely that DIMP will be bioaccumulated in animals and be present further up the food chain. 

FUN Tool. The 2FUN Tool provides outputs such as bioaccumulation of the substances in the target organs or concentrations in the human blood. In the present study the Pb concentration in the arterial blood of children/workers has been assessed. 

Sediments can also serve as potential exposure routes for aquatic food chains through the bioaccumulation of contaminants by benthic organisms. The potential of sediment contaminants to expose organisms in sediments and the water column is determined by their bioavailability. The bioavailability or bioaccessibility of nonpolar organic contaminants is determined by how strongly they are bound to organic matter in soil and sediment [31, 32]. This fact should be taken into account in a realistic assessment of the environmental risks of these contaminants (Fig. 13). 

Burger, J., K. Cooper, J. Saliva, D. Gochfeld, D. Lipsky, and M. Gochfeld. 1992. Mercury bioaccumulation in organisms from three Puerto Rican estuaries. Environ. Monitor. Assess. 22 181-197. 

Ward, G.S., G.C. Cramm, P.R. Parrish, H. Trachman, and A. Slesinger. 1981. Bioaccumulation and chronic toxicity of bis(tributyltin)oxide (TBTO) tests with a salt water fish. Pages 183-200 in D.R. Branson and K.L. Dickson (eds.). Aquatic Toxicology and Hazard Assessment fourth conference. ASTM Spec. Tech. Publ. 737, American Society for Testing and Materials, Philadelphia, PA. 

Ma, W.-C., A. Van Kleunen, J. Immerzeel, and P.G.-J. De Maagd. 1998. Bioaccumulation of polycyclic aromatic hydrocarbons by earthworms assessment of equilibrium partitioning theory in situ studies and water experiments. Environ. Toxicol. Chem. 17 1730-1737. 

Nendza, M. (1991). QSARs of bioconcentration validity assessment of logPow/ logBCF correlations. In Bioaccumulation in Aquatic Systems, eds. Nagel, R. and Loskill, R., Series, VCH, Weinheim, Germany, pp. 43-66. 

Spade, A., McCarty, L. S. and Rand, G. M. (1995). Bioaccumulation and bioavailability in multiphase systems. In Fundamentals of Aquatic Toxicology. Effects, Environmental Fate and Risk Assessment, ed. Rand, G. M., Taylor and Francis, Washington DC, pp. 493-522. 

Fish bioaccumulation study (or an expert assessment of bioaccumulation potential)... 

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