In the late ‘60s and early ‘70s a huge story broke out of Minamata Bay, Japan. There was a chemical factory that had been dumping mercury into the bay since the 1930s resulting in fish and shellfish extremely high in mercury and a population suffering from a variety of disabling and even fatal neurological disorders and birth defects. It was so bad that today the medical term for the symptoms of mercury poisoning is Minamata Syndrome, or Minamata Disease . According to the Japanese government, the factory was closed and the bay has since been cleaned up.
This was the first time many people had heard that mercury poisoning in fish was a problem and fish was struck off many people’s diets. Parents, especially, would not feed their children fish. I eat a lot of fish and shellfish because, (1) It’s available to me simply by dawning snorkel gear and jumping over the side, (2) I love most fish that school around here and they are plentiful: Amberjack, permit, grouper, flounder, redfish, porgy, and conch, scallops, oysters, clams, mussels, (3) Fish and shellfish contain high-quality protein and other essential nutrients, are low in saturated fat, and contain omega-3 fatty acids. A well-balanced diet that includes a variety of fish and shellfish can contribute to heart health. (4) I know the fish that are high in methylmercury and those with only trace amounts, The best grounds for shellfishing is at the mouths of the tiny, pristine rivers on the more mountainous islands here that empty into coves and bays. These are the best tasting and most healthy.
Shark and most billfish like swordfish and marlin are off my menu, as well as albacore tuna, king mackerel, or tilefish. White tuna have less mercury, but I rarely catch tuna at all. Fish store most of the mercury in the liver. Never eat the liver of a species known to retain mercury. Fish without livers, or “oily fish,” like the ones on the list above, store their oils throughout the body and mercury is in the fishoil.. I consider these fish inedible. I eat only fish with livers and throw the liver out, which is sad, because the fish oil normally is very good for you. I east fish in some form at least once a day, often three times a day. I wouldn’t be so strict about this if fish wasn’t such a large part of my diet. The waters here are quite unpolluted as there is no heavy industry in these parts of the islands. I’ve even used seawater in lieu of salt in soups. I often make fish stock by boiling coquinas and fish bones and heads in about 25% seawater. The subtle seeweed flavors add substance to fisherman bouillabaisse and paella. I have been bumming around down here eating from the sea for about a year and a half and have no signs or symptoms of Minamata disease. But I digress as usual.
The answer to the question is that Japan does have problems with mercury poisoning..