Polychlorinated Biphenyl Concentrations in Adult Chinook Salmon (Oncorhynchus tshawytscha) Returning to Coastal and Puget Sound Hatcheries of Washington State

• Published in: Environmental science & technology 2005-09, Vol.39 (18), p.6944-6951
• Main Authors: Missildine, Brian R, Peters, Roger J, Chin-Leo, Gerardo, Houck, Douglas
• Format: Article
• Language: English
• Subjects: Agnatha. Pisces; Animal, plant and microbial ecology; Animals; Applied ecology; Aroclors - analysis; Biological and medical sciences; Contamination; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; Environment; Environmental Monitoring - methods; Environmental Pollutants; Female; Fish Diseases; Fish hatcheries; Food Chain; Food Contamination; Fundamental and applied biological sciences. Psychology; Lipids; Male; Pacific Ocean; PCB; Polychlorinated biphenyls; Polychlorinated Biphenyls - analysis; Salmon; Standard deviation; Washington; Water Pollutants, Chemical - analysis
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es0506408

Identifying the source of polychlorinated biphenyls (PCBs) is the first step to eliminating contamination within anadromous salmonids and other aquatic species. We evaluated PCB concentrations in the muscle tissue of 4-year old Puget Sound and coastal hatchery Chinook salmon in an effort to identify potential locations where contamination occurs. Ten muscle samples were taken from each of two Puget Sound hatcheries and two coastal hatcheries in Washington State to determine PCB concentrations. Two technical mixtures of PCBs, Aroclor 1254 and Aroclor 1260, were measured in the tissue samples collected. Aroclor 1254 was detected in all samples, while Aroclor 1260 was detected in 16 of 40 samples. Generalized linear modeling (GLM) was used to evaluate the influence of region (Puget Sound and coast), hatchery, sex, fish length, and percent lipids on PCB concentrations. Twenty different GLMs representing multiple null hypotheses were ranked using Akaike Information Criterion (AIC). Six of the 20 models evaluated had substantial support for being the best model to describe PCB concentrations in Chinook salmon. The six models with substantial support were region and lipids; region; hatchery and lipid; region and sex; region, sex, and lipids; and region and length. Region appears to be the most influential variable explaining the variation in PCB concentrations in Chinook salmon in the Pacific Northwest. PCB concentrations in Chinook salmon muscle tissue from Puget Sound hatcheries were significantly greater (mean 49.26 μg/kg wet weight and standard deviation 40.55 μg/kg) than those from coastal hatcheries (mean 17.41 μg/kg wet weight and standard deviation 6.8 μg/kg). Our results suggest that some contamination likely occurs in the Pacific Ocean. However, a larger source likely exists within Puget Sound or along the migratory route of Puget Sound Chinook salmon. The observation of PCBs in Chinook salmon also has important implications for human health and salmon carcass supplementation.