I want to briefly talk about mercury. Mercury is a metal found in nature. It is as natural as sea-salt. It’s a wonderful example of why the word “natural” is not the same as “good.”
How toxic is mercury? According to its Material Safety Data Sheet at Fisher Scientific, it has a toxic dose of about 400 mg per kilogram body weight. At that level it causes tumors in 50% of lab rats. Nobody wants tumors, so I don’t recommend coming into contact with mercury at all. But at the same time let’s put that in perspective.
Table salt has a lethal dose of salt (not tumors – death) only about 8 times as high. that’s right, 3000 mg of salt per kg body weight can kill you (~50% chance of living). Should you avoid salt? No, you need salt. Just don’t gag down grams of it.
Mercury? You don’t need mercury for anything. So avoid it, especially if you are considering having children in the next month or two. But at the same time, don’t freak out about it. Compact fluorescent light bulbs contain a few milligrams of mercury. The post to which I linked is ridiculous. For instance, it quotes a air quality standard of 300 nanograms per cubic meter (of air!) and extrapolates that to soil concentration. Absurd.
The big upshot is that exposure to mercury is an increased risk factor, but so is a well made burger.