Define "normal consumption". Some bodybuilders and strength athletes eat large quantities of tuna as a low-fat source of protein; a non-trivial proportion of di

Define "normal consumption". Some bodybuilders and strength athletes eat large quantities of tuna as a low-fat source of protein; a non-trivial proportion of dieters rely on fish as their main source of protein. These may be unusually high levels of consumption, but they aren't edge cases and aren't prima facie stupid if you're unaware of the risk of mercury toxicity. A lot of smart, health-conscious people end up with dangerously high levels of mercury precisely because they believe that seafood is a healthy option and aren't aware of the risk of mercury exposure. https://www.ncbi.nlm.nih.gov/pubmed/12676623/ https://www.ncbi.nlm.nih.gov/pubmed/12676623/