Updated Risk/Benefit Analysis of Fish Consumption Effects on Neurodevelopment: Implications for Setting Advisories

ABSTRACT

Epidemiological studies indicate that fish consumption during pregnancy leads to improved neurodevelopment. This suggests that the beneficial nutrients in fish may offset the adverse effects of mercury in the case of the average fish meal. However, our previous risk/benefit model predicted a net neurodevelopmental risk for the majority of species analyzed. In this article the previous model is calibrated against fish benefit data and then compared to other fish risk/benefit models, including recent models from the World Health Organization and USFDA. Our calibrated model estimated greater benefit for low mercury species but greater risk for high mercury species than the other models. With respect to a commonly eaten high mercury fish, swordfish, the calibrated model yielded risks that are supportive of current fish advisories but, in contrast, the other models predicted net neurodevelopmental benefits. The calibrated model was used in a proposed 3 step framework for setting fish consumption advisories: (1) Set initial consumption level based upon mercury RfD; (2) Adjust consumption upward if risk/benefit model indicates a net benefit; (3) Cap fish consumption based upon saturation of O-3 benefit. The implications of this approach for 7 varieties of fish are used to illustrate the framework.

Key Words:

• Methyl mercury
• omega-3 fatty acids
• fish consumption
• fish oils
• neurodevelopment
• risk-benefit analysis
• risk assessment
• IQ
• visual recognition memory