Estimation of sport fish harvest for risk and hazard assessment of environmental contaminants

Consumption of contaminated fish flesh can be a significant route of human exposure to hazardous chemicals. Estimation of exposure resulting from the consumption of fish requires knowledge of fish consumption and contaminant levels in the edible portion of fish. Realistic figures of sport fish harvest are needed to estimate consumption. Estimates of freshwater sport fish harvest were developed from a review of 72 articles and reports. Descriptive statistics based on fishing pressure were derived from harvest data for four distinct groups of freshwater sport fish in three water types: streams, lakes, and reservoirs. Regression equations were developed to relate harvest to surface area fished where data bases were sufficiently large. Other aspects of estimating human exposure to contaminants in fish flesh that are discussed include use of bioaccumulation factors for trace metals and organic compounds. Using the bioaccumulation factor and the concentration of contaminants in water as variables in the exposure equation may also lead to less precise estimates of tissue concentration. For instance, muscle levels of contaminants may not increase proportionately with increases in water concentrations, leading to overestimation of risk. In addition, estimates of water concentration may be variable or expressed in a manner that does not truly represent biological availability of the contaminant. These factors are discussed. 45 refs., 1 fig., 7 tabs