title: Males exceed females in PCB concentrations of cisco (Coregonus artedi) from Lake Superior.
abstract: We determined whole-fish polychlorinated biphenyl (PCB) concentrations of 25 male and 25 female age-7 ciscoes (Coregonus artedi) captured from a spawning aggregation in Thunder Bay, Lake Superior, during November 2010. We also determined PCB concentrations in the ovaries and somatic tissue of five additional female ciscoes (ages 5-22). All 55 of these ciscoes were in ripe or nearly ripe condition. Bioenergetics modeling was used to determine the contribution of the growth dilution effect toward a difference in PCB concentrations between the sexes, as females grew substantially faster than males. Results showed that the PCB concentration of males (mean = 141 ng/g) was 43% greater than that of females (mean = 98 ng/g), and this difference was highly significant (P<0.0001). Mean PCB concentrations in the ovaries and the somatic tissue of the five females were 135 and 100 ng/g, respectively. Based on these PCB determinations for the ovaries and somatic tissue, we concluded that release of eggs by females at previous spawnings was not a contributing factor to the observed difference in PCB concentrations between the sexes. Bioenergetics modeling results indicated that the growth dilution effect could explain males being higher than females in PCB concentration by only 3-7%. We concluded that the higher PCB concentration in males was most likely due to higher rate of energy expenditure, originating from greater activity and a higher resting metabolic rate. Mean PCB concentration in the cisco eggs was well below the U. S. Food and Drug Administration and Ontario Ministry of Environment guidelines of 2000 and 844 ng/g, respectively, and this finding may have implications for the cisco roe fishery currently operating in Lake Superior.
authors: U. S. Geological Survey, Great Lakes Science Center, 1451 Green Road, Ann Arbor, MI 48105, USA. Electronic address: cmadenjian@usgs.gov.
authors: Charles P
authors: CP
authors: Madenjian
authors: U. S. Geological Survey, Great Lakes Science Center, Lake Superior Biological Station, 2800 Lakeshore Drive, Ashland, WI 54806, USA. Electronic address: dyule@usgs.gov.
authors: Daniel L
authors: DL
authors: Yule
authors: University of Michigan, School of Public Health, 1420 Washington Heights, Ann Arbor, MI 48109, USA. Electronic address: sergeic@umich.edu.
authors: Sergei M
authors: SM
authors: Chernyak
authors: U. S. Geological Survey, Great Lakes Science Center, 1451 Green Road, Ann Arbor, MI 48105, USA. Electronic address: lbegnoche@usgs.gov.
authors: Linda J
authors: LJ
authors: Begnoche
authors: Ontario Ministry of Natural Resources, Upper Great Lakes Management Unit of Lake Superior, 435 James Street South, Suite 221e, Thunder Bay, ON P7E 6S8, Canada. Electronic address: eric.berglund@ontario.ca.
authors: Eric K
authors: EK
authors: Berglund
authors: Grand Portage Band of Lake Superior Chippewa, 27 Stone Road, Grand, Portage, MN 55605, USA. Electronic address: ejisaac@boreal.org.
authors: Edmund J
authors: EJ
authors: Isaac
mesh_terms: D000818:Animals; D004784:Environmental Monitoring; D005260:Female; D005399:Fishes / Q000378:metabolism*; D060106:Lakes; D008297:Male; D009864:Ontario; D011078:Polychlorinated Biphenyls / Q000378:metabolism*; D012737:Sex Factors; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D014874:Water Pollutants, Chemical; D011078:Polychlorinated Biphenyls
keywords: Activity; Consumption advisories; Gross growth efficiency; Lake herring; Planktivore; Standard metabolic rate