Occurrence of retene and resin acids in sediments and fish bile from a lake receiving pulp and paper mill effluents

Retene (7‐isopropyl−1‐methylphenanthrene) is a dialkyl‐substituted PAH derived thermally and microbially from dehydroabietic acid. We have analyzed for retene and several resin acids in sediments at five depths at several sites in a lake receiving effluents from three pulp and paper mills, and two upstream reference sites. The highest concentration of retene was 1,600 μg/g dry weight (11,700 μg/g organic carbon [OC]) and of total resin acids was 1,500 μg/g dry weight (9,300 μg/g OC). Twelve kilometers downstream from the point of bleached‐kraft mill effluent (BKME) discharge, the concentration of retene at a depth of 5 to 10 cm was 16 μg/g dry weight (650 μg/g OC) and of resin acids was 139 μg/g dry weight (1,700 μg/g OC). Upstream of the BKME discharge, the concentration of retene was below 0.1 μg/g dry weight and of resin acids was below 70 μg/g dry weight. To assess the bioavailability of retene to fish we determined its concentration in the bile of roach ( Rutilus rutilus ) and perch ( Perca fluviatilis ) caught 1 to 2 km downstream of pulp and paper mills and in the reference area. Retene was bioavailable to roach, which primarily feed on benthic organisms; however, retene was not detected in perch bile.