Good Healthy Fish

It's wonderful that you care about fish populations as well as your family's health. The good news is that there are still lots of fish, rich in protein and heart-healthy omega-3 fatty acids, that are low in toxins and not overfished. These include wild Alaskan salmon, which can be bought fresh from April through September and frozen or canned the rest of the year, and sardines (which are high in calcium). Here's a breakdown of the toxins most commonly found in fish, and how to avoid them.

Mercury
Because you're pregnant and have a young child, you have good reason to be cautious about dietary exposure to mercury, which is found at highest levels in some species, such as tuna and swordfish. Fetuses, infants and young children, whose brains and nervous systems are rapidly developing, are at greatest risk of harm from neurotoxins such as mercury. "Mercury ingested during pregnancy can damage an unborn baby's central nervous system, leaving the baby with slower than normal brain development," Philip J. Landrigan, M.D. and Herbert L. Needleman, M.D. write in Raising Healthy Children in a Toxic World (Rodale, 2001).

Because mercury is stored in our body fat, just as it is in fish, women planning to have children should also avoid high-mercury fish well before they become pregnant. According to the Centers for Disease Control, 8 percent of American women have levels of mercury in their blood that could prove harmful to fetuses. Adults can suffer harm, as well: In April, 2003, Environmental Health Perspectives reported that 89 percent of fish-eating subjects had blood mercury levels above the safety threshold of 5 micrograms per liter; several showed symptoms of mercury poisoning such as fatigue, decreased memory and joint pain.

The Food and Drug Administration (FDA) and Environmental Protection Agency (EPA) advise that, in general, young children, pregnant women, nursing mothers and women of childbearing age should eat no more than two or three meals, or 12 ounces, of fish and shellfish a week. High-mercury fish-shark, swordfish, king mackerel, tilefish and tuna- should be limited to no more than 4-6 ounces once a week for these individuals. But some environmental health organizations, including the Environmental Working Group (EWG), have been recommending that people in these high-risk groups eat moderate-mercury fish no more than once a month, and high-mercury fish not at all. In fact, earlier versions of a December, 2003 FDA/ EPA draft advisory on fish suggested that high-risk individuals completely avoid high-mercury fish; however, this proscription did not appear in the draft that was released. Also in December, after being pressed to do so for years by EWG and others, FDA finally added tuna to the list of fish that should be eaten no more than once a week.

Persistent Organic Pollutants (POPs)
Polychlorinated biphenyls (PCBs), banned in the U.S. since 1978, were found at far higher levels in farmed than wild salmon, according to a study released in January 2004, include, members of a class of chemicals known as persistent organic pollutants, or POPs. Like mercury, POPs accumulate in animal fats and rise in the food chain, so that large predator fish will generally contain higher amounts. Because farmed salmon are raised on feed that includes ground-up animals and fish, their bodies accumulate these pollutants. Other POPs found in fish include the organochlorine pesticide dieldrin and dioxins-- the result of chlorine paper bleaching and manufacturing and incineration of PVC plastic, and the most toxic man-made chemicals known.

PCBs, which are neurotoxins, hormone disruptors and probable carcinogens, were found at levels seven times higher in farmed than in wild salmon. PCBs are also found at high levels in fish from polluted water bodies, varying from locale to locale; state health advisories list which fish should not be consumed by children, pregnant or nursing women, and women of childbearing age.

How to Avoid Fishborne Toxins

Avoiding Mercury
As a general rule, The Green Guide and our medical advisory board, including Drs. Landrigan and Needleman, agree with EWG's guidelines.

*Young children and pregnant or nursing women should not eat high-mercury fish, and should limit meals of moderate-mercury fish to once a month.
(This is a general rule, however, which means you shouldn't worry unduly if you or your child occasionally get your fish mixed up and eat the "wrong" kind. A once-in-a-while meal won't cause harm-it's regular ingestion that allows mercury to build up in the body.)

*Know your tuna: According to the FDA, tuna steak and canned albacore (white) tuna generally contain up to three times more mercury than canned light tuna. According to EWG guidelines, a pregnant woman or young child can eat 4-6 ounces of moderate-mercury, canned light tuna (one sandwich) per month.

*Fish lowest in mercury include: Wild Alaskan salmon, sardines, squid, Arctic char, flounder, sanddabs, scallops and sole. For moderate and high mercury fish lists, and which fish are from healthy, recovering or overfished populations, see www.thegreenguide.com

Avoiding POPs
Check with the state department of health before eating fish from local fresh or ocean waters, as worrisome levels of PCBs as well as pesticides and other industrial chemicals may be present.

In General
*Limit fish consumption by category, not individual species. For example, both cod and mahimahi are moderate-mercury fish, and only one from this category should be eaten per month -not one meal of cod and one of mahimahi.

*Don't eat the skin and fatty parts of fish, where toxins collect.

*Eat cooked rather than raw fish, as cooking, particularly grilling, burns off fat.

*For lists of specific fish can be eaten regularly, once in a while, and not at all ("yes," "sometimes" and "no") fish, visit thegreenguide.com. A unique, downloadable pocket fish guide, "Smart Shopper's Fish Picks," addresses both overfishing and pollutants in fish that threaten human health. It is regularly updated.

For more information, also see www.fda.gov, www.ewg.org, www.epa.gov/waterscience/ fish and www.map1.epa.gov to learn which fish from which water bodies are currently safe or unsafe to eat.