Bioconcentration factor

The BCF measures the potential of a chemical to accumulate in biota that lives in an aquatic environment. BCF does not consider uptake from diet, which is taken into 

BCF is measured under controlled laboratory conditions and it is the ratio between biota and water concentrations of a given chemical. BCF is important in order to establish if long-term exposures to external low concentrations of a substance can lead to a high internal concentration due to the accumulation of the substance within the organism. 

BCF can also be estimated and Kow is the starting indicator. A linear correlation between BCF and Kow has been established for nonionic, slowly metabolised substances with log Kow between 1 and 6. Substances with log Kow 6 have a lower BCF than would be predicted by a linear relationship because the low aqueous solubility reduces bioavailability hence for substances with log Kow 6, BCF decreases and a parabolic/bilinear model can be applied [29]. 

According to REACH, a bioaccumulation study need not be conducted if  

It should be noted that the final compartment directly relevant to biodegradable plastics is soil, both for agricultural items and for those items which end up in composting plants. Hence BCF evaluation is only needed if the Koc of a substance indicates that the substance will preferably move to the water compartment. 

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Bioconcentration, Bio accumulation and Biomagnification. These aspects are determined by the physicochemical properties of a chemical, an organism s ability to excrete the chemical, the organism s lipid content and its trophic level. Bioconcentration relates to the difference between the environmental concentration and that of the body tissues. A high bioconcentration factor (BCF) predisposes to bioaccnmulation. The upper limit of bioaccnmulation is determined by lipid levels in the organism s tissues. Whether the resultant body burden causes biomagnification in the food chain depends upon the metabolic capabilities of the exposed organism. 

Estimates of bioconcentration factors, BCE, in aquatic organisms, based on calculations from water solubility and gave a log BCE of 1.80-2.89 (Kenaga 1980). Studies in outdoor ponds yielded log... 

Kenaga EE. 1980. Predicted bioconcentration factors and soil sorption coefficients of pesticides and other chemicals. Ecotoxicol Environ Safety 4 26-38. 

Bioconcentration Factor (BCE)—The quotient of the concentration of a chemical in aquatic organisms at a specific time or during a discrete time period of exposure divided by the concentration in the surrounding water at the same time or during the same period. 

Endosulfan does not bioaccumulate to high concentrations in terrestrial or aquatic ecosystems. In aquatic ecosystems, residue levels in fish generally peak within 7 days to 2 weeks of continuous exposure to endosulfan. Maximum bioconcentration factors (BCFs) are usually less than 3,000, and residues are eliminated within 2 weeks of transfer to clean water (NRCC 1975). A maximum BCE of 600 was reported for a-endosulfan in mussel tissue (Ernst 1977). In a similar study, endosulfan, isomers not specified, had a measured BCE of 22.5 in mussel tissue (Roberts 1972). Tissue concentrations of a-endosulfan fell rapidly upon transfer of the organisms to fresh seawater for example, a depuration half-life of 34 hours (Ernst 1977). Higher BCFs were reported for whole-body and edible tissues of striped mullet (maximum BCF=2,755) after 28 days of exposure to endosulfan in seawater (Schimmel et al. 1977). However, tissue concentrations decreased to undetectable levels 48 hours after the organisms were transferred to uncontaminated seawater. Similarly, a BCE of 2,650 was obtained for zebra fish exposed to 0.3 pg/L of endosulfan for 21 days in a flow-through aquarium (Toledo and Jonsson 1992). It was noted that endosulfan depuration by fish was rapid, with approximately 81% total endosulfan eliminated within 120 hours when the fish were placed in a tank of water containing no endosulfan. 

BCF = bioconcentration factor, 270 L/kg for alpha-, beta-endosulfan, and endosulfan sulfate WCR = water consumption rate, set at 2 L/day... 

Biomagnification along aquatic food chains may be the consequence of bioconcentration as well as bioaccumulation. Aquatic vertebrates and invertebrates can absorb pollutants from ambient water bottom feeders can take up pollutants from sediments. The bioconcentration factor (BCF) of a chemical absorbed directly from water is defined as... 

There have been a nnmber of estimates of bioconcentration factors for total PCBs in aqnatic species following long-term exposure to PCB mixtures (EHC 140). Values for both invertebrates and hsh have been extremely variable, ranging from values below 1 to many thonsands. Bioaccnmnlation factors for birds and mammals for different Aroclors have indicated only limited degrees of bioaccumulation from food, for example, 6.6 and 14.8 for the whole carcasses of big brown bats Eptesicus fuscus) and white pelican (Pelecanus erythrorhynchos), respectively (see Environmental Health Criteria 140). 

Bioconcentration factor (BCF) Concentration of a chemical in an organism or concentration of same chemical in the ambient medium. 

Experimentally measured bioconcentration factors (BCFs), which provide an indication of the tendency of a chemical to partition to the fatty tissue of organisms, have been found to range between 10 and 100 for trichloroethylene in fish (Kawasaki 1980 Kenaga 1980 Neely et al. 1974 Veith et al. 1980). Barrows et al. (1980) estimated a value of 17 for bluegill sunfish. Somewhat lower BCFs were determined by Saisho et al. (1994) for blue mussel (4.52) and killifish (2.71). These numbers are suggestive of a low tendency to bioaccumulate. 

Veith GD, Macek KJ, Petrocelli SR, et al. 1980. An evaluation of using partition coefficients and water solubility to estimate bioconcentration factors for organic chemicals in fish. In Eaton JG, Parrish PR,... 

Niimi AJ, HB Lee, GP Kissoon (1989) Octanol/water partition coefficients and bioconcentration factors of chloronitrobenzenes in rainbow trout Salmo gairdneri) Environ Toxicol Client 8 817-823. 

DOE. 1996. Radiological bioconcentration factors for aquatic, terrestrial, and wetland ecosystems at the Savannah River Site (U). Savannah River Site. U.S. Department of Energy. WSRC-TR-96-0231. DE-AC09-89SR18035. 

Fisher NS, Fowler SW, Boisson F, et al. 1999. Radionuclide bioconcentration factors and sediment partition coefficients in Arctic seas subject to contamination from dumped nuclear wastes. Environ Sci Technol33 1979-1982. 

Bioconcentration Factors for Components of Organophosphate Ester Hydraulic Fluids... 

Veith GD, Delore DL, Bergstedt BV. 1979. Measuring and estimating the bioconcentration factor of chemicals in fish. Journal of the Fish Research Board of Canada 36 1040-1048. 

Agency for Toxic Substances and Disease Registry bioconcentration factor Board of Scientific Counselors Centigrade... 

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