Bioconcentration factor silver

Silver is a normal trace constituent of many organisms (Smith and Carson 1977). In terrestrial plants, silver concentrations are usually less than 1.0 mg/kg ash weight (equivalent to less than 0.1 mg/kg DW) and are higher in trees, shrubs, and other plants near regions of silver mining. Seeds, nuts, and fruits usually contain higher silver concentrations than other plant parts (USEPA 1980). Silver accumulations in marine algae (max. 14.1 mg/kg DW) are due mainly to adsorption rather than uptake bioconcentration factors of 13,000 to 66,000 are not uncommon (USPHS 1990 Ratte 1999). 

Falandysz, J. and D. Danisiewicz. 1995. Bioconcentration factors (BCF) of silver in wild Agaricus campestris. Bull. Environ. Contam. Toxicol. 55 122-129. 

Silver accumulation in marine algae appears to result from adsorption rather than uptake bioconcentration factors of 13,000-66,000 have been reported (Fisher et al. 1984). 

Data on the potential for accumulation of silver has been studied in several aquatic species. Several of these studies do not conform to current bioconcentration test procedures in terms of numbers of fish, duration of exposure, and measurement of concentrations in aquaria. EPA (1980a) reported a bioconcentration factor of less than I in bluegills (Lepomis macrochirus) exposed to silver nitrate for 28 days. Approximate bioaccumulation factors of 4-6 for bluegill were calculated based on a 6-month study and 2-10 for large mouth bass (Micropterus salmoides) exposed to silver nitrate for 4 months (both dry weight) (Coleman and Cearley 1974). 

The ability to accumulate dissolved silver from the medium ranges widely between species. Some reported bioconcentration factors (mg Ag per kg EW organism/mg Ag per liter of medium) are 210 in diatoms, 240 in brown algae, 330 in mussels, 2300 in scallops, and 18,700 in oysters. Silver is the most strongly accumulated of all trace metals by marine bivalve mollusks. Studies with radiosilver-llOm suggest that the half-time... 

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