Bioaccumulation potential

Naqvi SM, Vaishnavi C. 1993. Mini Review. Bioaccumulative potential and toxicity of endosulfan insecticide to non-target animals. Comp Biochem Physiol C 105(3) 347-61. 

Food Chain Bioaccumulation. Information is available regarding bioaccumulation potential in aquatic food chains. Studies show that trichloroethylene has a low-to-moderate bioconcentration potential in aquatic organisms (Pearson and McConnell 1975) and some plants (Schroll et al. 1994). Information is needed, however, regarding bioaccumulation potential in terrestrial food chains. 

Harvey J, JJ Dulka, JJ Anderson (1985) Properties of sulfometuroin methyl affecting its environmental fate aqueous hydrolysis and photolysis, mobility and adsorption on soils, and bioaccumulation potential. J Agric Food Chem 33 590-596. 

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 bioconcentration factor, although usually related to fish is actually an estimate of the bioaccumulation potential for biota in general. Different organisms may bioconcentrate a given chemical to a lesser or greater degree, however with different chemicals, the relative ranking with respect to bioconcentration will be essentially the same for all species. 

Southworth, G.R., Beauchamp, J.J., Schmieders, P.K. (1978) Bioaccumulation potential of polycyclic aromatic hydrocarbons in Daphnia Pulex. Water Res. 12, 973-977. 

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

The rapid degradation of molinate and conversion to more polar metabolites which are excreted into water serves to explain the extremely low bioaccumulation potential of this herbicide in fish. 

The discovery that microbial dechlorination of PCBs was occurring in many aquatic sediments brought the hope that this process would provide a natural means of remediation [371,451]. Dechlorination decreases the bioaccumulation potential of PCBs by making them more degradable and is expected to decrease the potential toxicity of PCBs [2,34,105,371,451-453]. Extensive microbial dechlorination of PCBs has occurred in some aquatic sediments including those of the Hudson River (NY) and Silver Lake (Pittsfield, MA) [371]. 

Research at Colorado State University (FEDRIP 1994) will investigate toxicity and bioaccumulation potential of chloroform and other organic and inorganic chemicals. The laboratory studies will use a simple food chain containing larval invertebrates and fish. The results would be applicable to many natural systems with fish foraging on insect larvae in contaminated sediments. 

In many cases, hazard based substitution eliminates the need for notoriously difficult exposure assessment. Persistence and bioaccumulation potential are surrogate measures of both hazard and exposure that can be applied quickly to all chemicals In order to identify those of greatest concern. 

The RoHS Directive was a major catalyst for research and adoption of lead-free solutions in electronic equipment. Alternatives to lead in soldering range from tin (Sn), silver (Ag) and copper (Cu) to bismuth (Bi) and zinc (Zn). These heavy metals do not have the same toxicity and bioaccumulation potential of lead (Pb). ... 

Renberg, L.O., Sundstrom, S.G., and Rosen-Olofsson, A.-C. The determination of partition coefficients of organic compounds in technical products and waste waters for the estimation of their bioaccumulation potential using reversed phase thin layer chromatography, Toxicol. Environ. Chem., 10 333-349, 1985. 

Most compounds with such high BCF and Log Ko values are highly bioaccumulative. The cychc siloxanes, however, also have a high rate of clearance from the body through exhaled breath and a fast metabolism, so they might not be as bioaccumulative as the BCF and Log ATqw values indicate [285, 294, 295]. Kierkegaard et al. [284] compared the bioaccumulation potential of D4, D5, and D6 with the one of PCB 180, a compound known to be very bioaccumulative. D5 was found to be more bioaccumulative than PCB 180 and D4 even more so. D6, however, was found to have a lower bioaccumulation potential than PCB 180. 

The partition coefficient Kq of an organic compound in the 1-octanol/water system is used to assess the bioaccumulation potential and the distribution pattern of drugs and pollutants. The partition coefficient of imidazole and ILs strongly depends on the hydrogen bond formed by these molecules and is less than one due to the high solubility in water. The low value of the 1-octanol/water partition coefficient is required for new substances, solvents, insecticides to avoid bioaccumulation. Kqw is an extremely important quantity because it is the basis of correlations to calculate bioaccumulation, toxicity, and sorption to soils and sediments. Computing the activity of a chemical in human, fish, or animal lipid, which is where pollutants that are hydrophobic will appear, is a difficult task. Thus, it is simpler to measure the 1-octanol/water partition coefficient. This parameter is used as the primary parameter characterizing hydrophobisity. 

The problem of toxic pollutants is difficult to handle because of the great variety of chemicals involved. They represent a hazard not only to aquatic life, but also to human health, either through direct exposure or indirectly through consumption of contaminated fish or waterfowl. The degree of hazard depends on the pollutanf s toxicity, rate of discharge, persistence and distribution in the aquatic system, and bioaccumulation potential. Some highly volatile compounds, when discharged into water, evaporate and become air pollutants. 

Food Chain Bioaccumulation. Because of the rapid hydrolysis of HDI in water and the ease with which this substance is metabolized in higher trophic animals (see Section 2.3), it is not expected that this substance will bioconcentrate in aquatic organisms, or bioaccumulate in the food chain. Neither TDI and MDl, nor their diamine hydrolysis products, TDA and MDA, have been found to bioaccumulate in fish (Cyprinus carpio) in river model studies (International Isocyanate Institute 1990). No information on BCFs and food chain bioaccmnulation could be foimd for HDI in the available literature however, a BCF of approximately 100 was calculated using the method of Veith et al. (1979), which indicates a very low bioaccumulation potential for HDI. Further studies on the bioaccumulation of HDI do not appear to be warranted. 

Octanol/Water Partition Coefficient (Kow) — the equilibrium ratio of the concentrations of material partitioned between octanol and water. This coefficient is considered to be an index of the potential of a chemical to be bioaccumulated. Higher values of K, are associated with greater bioaccumulative potential. 

No significant bioaccumulation potential or Potential to bioaccumulate in aquatic organisms. 

In the literature, the estimated chemical s equilibrium concentration, C b , in the organism (i.e., the numerator of Eq. 10-3) is called the theoretical bioaccumulation potential, TBPh and is given by ... 

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