Bioconcentration of Chlorophenols by Juvenile Chinook Salmon (Oncorhynchus tshawytscha) Overwintering in the Upper Fraser River: Field and Laboratory Tests

Abstract

Abstract Juvenile chinook salmon were sampled from August 1986 to March 1987 at stations near Prince George and Quesnel, influenced by sewage and pulp mill discharges. Maximum densities of 0.2 fish·mࢤ2 were recorded. Salmon were collected at reference sites in November 1986 and at Agassiz in April 1987. Fingerling chinook were exposed at 0.7°C to a commercial wood preservative containing 2,3,4,6 - tetrachlorophenol (TeCP) and pentachlorophenol (PCP) in the laboratory to simulate winter conditions in the upper Fraser River. Fish exposed for 62 days to 2 ug·Lࢤ1 contained a mean of 224 ng·gࢤ1 TeCP and 431 ng·gࢤ1 PCP. Chlorophenol uptake in feral fish was low. However, 3,4,5-trichloro-guaiacol levels to 304 ng·gࢤ1 and tetrachloroguaiacol values to 136 ng·gࢤ1 were measured in March. Fish from Agassiz, 518 km downstream of Quesnel, also contained these two substances. Thus chinook salmon can bioconcentrate persistent chlorophenols and chloroguaiacols directly from cold water (< 1°C). The biological consequences are uncertain.