Mercury Contamination: A Critical Issue

New evidence substantiating a variety of health benefits of LCP supplementation is being published month after month. Unfortunately, at the same time, concerns have been raised about the possible contamination of some fish that provide the critical fatty acids found in LCP supplements.

Last month the FDA advised pregnant women and women of childbearing age who may become pregnant (as well as nursing mothers and young children) not to eat shark, swordfish, king mackerel and tilefish. These fish, said the FDA, may contain high levels of a mercury called methyl mercury that may harm an unborn baby’s developing nervous system. Some experts on the ABC television show 20/20 also advised against eating tuna, but the FDA rejected calls to put tuna on the do-not-eat list stressing that swordfish and shark have far higher levels of mercury.

As you’re probably aware mackerel and tuna contain significant quantities of the fatty acids DHA and EPA and are often the source of these nutrients manufactured in fish oil capsules.

It is quite understandable that many parents giving such supplements to help their children with ADHD, dyslexia and dyspraxia (or taking omega-3 for personal health reasons) should be alarmed by the contamination reports. It is a serious issue and before making any recommendations it is worth reviewing the history of the problem.

The Mad Cats of Minamata

The danger of mercury contamination was discovered in 1953 when fish, contaminated with mercury, first drove cats mad and then killed and maimed people in a fishing village in Minamata Bay, Japan.

Mercury is one of a group of substances called heavy metals. Other members of the group include selenium, chromium, cadmium, manganese and lead. Some of these heavy metals are essential in the diet (selenium, chromium and manganese), but all of them are toxic when taken in excessive amounts.

There are three forms of mercury that are used by industry––metallic mercury, organic mercury compounds and inorganic compounds. All forms of mercury are poisons but some are less dangerous than others are. The inorganic forms are the least dangerous and the organic forms (for example, methyl mercury) the most dangerous. Unfortunately, when industrial waste including inorganic mercury is discharged into rivers, lakes and the sea, the sediments including microorganisms and animal life convert it to the more toxic organic methyl mercury. This is what happened in Minamata Bay and is happening in contaminated lakes, estuaries and rivers worldwide today. And this is what concerns the FDA and the Environmental Protection Agency (EPA). The greatest risk is from the fish mentioned by the FDA because they are long-lived, larger fish that feed on smaller fish and therefore accumulate the highest levels of methyl mercury. These fish would be perfectly safe to eat if they lived in uncontaminated waters. Much of the tuna that’s caught lives in clean South Pacific waters.

So, What Should You Do?

Unfortunately, the very groups of people advised not to eat king mackerel and tuna are those with a great need for the fatty acids that these fish contain––anyone likely to get pregnant, moms-to-be, nursing mothers and young children. It is a great pity that the safety of these fish is in question, but the advice must be heeded and only uncontaminated fish consumed. The EPA has information on which places are contaminated and where fish is safe to eat.

Most people, of course, now choose to obtain the vital fatty acids by consuming fish oil supplements such as those mentioned in my book, “The LCP Solution: The Remarkable Nutritional Treatment for ADHD, Dyslexia and Dyspraxia.” Reputable manufacturers of fish oil supplements regularly monitor their products for heavy metal contamination, so one way to get around the problem is to take a fish oil supplement that is free from such contaminants.

How can you be sure? A large, reputable manufacturer is going to do everything in its power to ensure that its products are not contaminated. It is not worth its while running the commercial risk of putting such products into the marketplace. But be an aggressive consumer! Contact the manufacturer of your preferred fish oil supplement. Ask them directly if their product contains mercury and if they screen every batch of fish oil they use. If you obtain a quick response and an explanation of how they monitor their product you can be reassured of its safety.

Best wishes,
Dr. Jackie Stordy and Malcolm Nicholl