Bioaccumulation of chlorinated paraffin residues in fish fed chlorowax 500C.

Fingerling rainbow trout were fed a diet fortified with 10 ppm Chlorowax 500C, a chlorinated paraffin, for up to 82 days. Chlorinated paraffin residues as high as 1.1 ppm (tissue basis) were found. Recoveries from fortified fish tissue were greater than 92%, and the method sensitivity (tissue basis) is at least 0.5 ppm. Ultraviolet irradiation of the sample extracts and microcoulometric gas chromatography minimized interferences. No gross toxicological effects were noted in the experimental fish, although their weight gain was less than that of the controls.