SPSG #10: The Paradigm War

Methylmercury in fish has been a major issue for both the EPA and the FDA since several epidemics occurred in Japan and Iraq in the 60s and 70s. At about the same time (early 90s) as the FDA started quantifying risks for methylmercury in fish and issuing consumer advice for commercial seafood, the EPA started giving recreational fish consumption advice based on the EPA Reference Dose (RfD). In 1999 congress asked the National Academy of Science (NAS) to evaluate the RfD for methylmercury, and a report was issued in 2000. The fact that congress even asked the question of the NAS cemented in many people minds that the RfD was and is a statement of a scientific fact. That meant that if it was true for EPA then it had to be true for FDA too, and as a result any attempt to quantify the risks and provide information about what the risks came to be viewed as a political attempt to undercut the science. By 2004, the FDA and EPA had agreed to give joint advice for fish consumption, but there was no agreement about what the basis or the rationale for the fish advisory was. While the EPA thought the RfD was paramount, the FDA chose to pursue a quantitative strategy that balanced benefits and risks; so the fish-risk benefit assessment was an FDA-only affair. But perhaps the most important difference was about what information, if any, would be given to consumers. The RfD treats consumers in the same manner as it treats agency managers; it decides for them, and as a result there is no basis for providing the information to consumers that will let them decide for themselves. As an alternative, a few representative risk estimates are provided for the consumption of fish during pregnancy using a version of the risk assessment model developed for the FDA that is designed to estimate risks for individual consumers.