The bioaccumulation factor for phosphorus-32 in edible fish tissue.

Abstract

Information used to derive the bioaccumulation factor for 32P in edible portions of fish was reviewed to evaluate the currently recommended values of 100,000 in fresh water and 29,000 in sea water that are applied in calculating radiation doses to persons from nuclear-power reactor effluents. A generic phosphorus bioaccumulation factor of 70,000 was obtained for larger rivers and estuarine waters on the basis of geometric mean phosphorus concentrations of 2 mg/g wet weight in fish muscle and 0.03 mg/l dissolved in water. A 20-fold lower bioaccumulation factor was inferred for 32P because radioactive decay is much faster than phosphorus turnover. A phosphorus turnover rate in muscle of 0.2% per day was estimated as a long-term average for edible-size fish, although more rapid turnover has been observed for brief periods. Large deviations from the generic bioaccumulation factor will occur for different phosphorus concentrations in water and turnover rates in fish. Site-specific determinations are also needed because 32P is bioaccumulated at lower trophic levels in the food web, not in the fish. Hence, the availability of concentrating organisms determines the bioaccumulation factor. Several other conditions that affect the 32P bioaccumulation factor have not been quantified and are suggested for study.