Our menhaden fish meal supply is sustainable harvest certified, and it must be wild caught for it's use in certified organic products. The producer has also agreed to supply me with an analysis of each batch produced for us. To verify their claims, we also test the fish for nutrition. The meals are tested for toxins and more intensively, for mercury. Neither our fish, nor our crab have ever had mercury levels of more than 0.01ppm by wet weight. The Stone Crab meal comes from Nova Scotia to Mexico. It's crab that didn't pass the visual test for human consumption, but it is nutritionally equivalent. The crab meal is what we call a sustainable reutilization process because it would otherwise end up in a landfill. Both the fish and the crab are cooked, dried, and then milled into meals.
Fish meal can have higher levels of mercury, but that largely depends on what type of fish is used to produce the fish meal. At Coyote Creek Organic Feed Mill, we only use naturally preserved menhaden fish meal. Very few feed mills use menhaden fish meal, and even fewer use naturally preserved fish meals. Typically, cheap white fish meals are used, and they tend to have much higher levels of mercury.
Not all fish meal is of the same quality, though in all the menhaden fish meal that is produced, mercury is not a concern. Mother Jones states, "If you're concerned about high mercury levels in farmed salmon or tuna, menhaden may start to sound more appealing. Unlike most fatty fish, plankton-swilling menhaden eat near the bottom of the food chain and have low mercury levels, 0.01 ppm (wet weight)." In addition, the Greenpeace Research Lab published the following study
comparing mercury levels in menhaden fish meal to fish oils. The research confirms the statements made by Mother Jones.
Beyond mercury in the fish, a big concern with fish meal is how the product is preserved. Most fish meal, like you stated, have been preserved with ethoxyquin or other highly toxic preservatives. Our fish meal is preserved with Naturox IPO antioxidant. It has an organic sunflower oil base carrier.