Having lived many years in the southwest desert, I was out of touch with the rhetoric of fish advisories. And the information I had then only provided pieces of an incomplete puzzle. Here I re-assess my hurried advice. If you are a sports fisherman, you receive literature along with your fishing license advising you how often you may eat different species and sizes of fish, what waters you can safely fish, and how to prepare fish in ways that reduce contaminant levels.
Various websites offer the same information, addressed to consumers of sports-caught fish.
But references to commercially purchased fish are nearly non existent in these advisories. There are laws to limit them, but extra caution will help protect unborn and young children. While the state sets the contaminant guidelines for sports-caught fish, the FDA determines what fish can be commercially marketed. The differences between the two systems call for examination. But first a distinction within the commercial market needs to be made between commercially caught wild fish, and farm-raised fish.