Is eating seafood becoming risky business?
By Chris O'Brien
Photos by Rita Maas
Fish has long been revered as a healthy, abundant and delicious alternative to meat. But aquatic delicacies might not be as healthy or ecologically prudent as once thought. Recent findings of toxic chemicals in fish, and a dwindling supply of some species, have led health and environment specialists to suggest scaling back on seafood. The best way to make a healthy choice is to know the risk factors for each species.
Taking The Temperature On Mercury
Hot topic: The mercury issue. High levels of mercury in certain fish have been connected to fetal damage and the underdevelopment of children's brains. In fact, the Food and Drug Administration (FDA) has issued a warning to pregnant and nursing mothers to avoid high-risk species such as tuna, shark, swordfish, king mackerel and tilefish, as well as recreationally caught fish. As an alternative, the FDA recommends up to 12 ounces per week of cooked fish including shellfish, some canned fish, smaller ocean fish and farm-raised fish.
"When contaminated fish is eaten, the mercury goes from the stomach into the bloodstream, then into the placenta and accumulates in the fetal brain," says Jane Houlihan, research director at the Environmental Working Group (EWG) in Washington, D.C. The most common effect of mercury exposure is learning disabilities in children, but in high doses it has been known to cause retardation, cerebral palsy and seizures. Mercury is a lot like lead in terms of the effect it has on children, but it does so at much lower doses, Houlihan says. And it can hurt adults too.
According to Houlihan, emerging research is pointing to cardiovascular disease as an adult risk from mercury toxicity. "The researchers were studying Finnish fishermen and hypothesized that because they ate a lot of fish they would have a lower incidence of heart disease," Houlihan says. "But the scientists were surprised to find out that the fishermen were two to three times more likely to die of a heart attack. It appears that methyl mercury damages the heart muscle."
So where does this nasty toxin come from? Most mercury found in fish begins its journey in the noxious fumes from coal-burning power plants. The mercury then concentrates in clouds, returns to the earth in rain, and winds up in streams, rivers, lakes and the ocean. From there, it works its way up the food chain.
"Generally speaking, the fish that have the highest levels of mercury are at the top of the food chain, like shark and swordfish," says Henry Lovejoy, president of EcoFish in Portsmouth, N.H. "And there really is no safe haven—they are finding high levels of mercury in fish from the farthest reaches of the ocean."
And those far reaches may be closer than you think. According to "Brain Food," a collaborative report from EWG and the U.S. Public Interest Research Group (U.S. PIRG), there's a growing number of fish that women of childbearing age should eat with caution. In addition to absolutely avoiding shark, swordfish, tuna steak, king mackerel and other predatory, top-of-the-chain fish, pregnant women should limit their intake of canned tuna, mahi-mahi and cod to one meal per month.
Expectant mothers should watch their mercury intake because each year more than 60,000 babies are born with mercury-related brain damage in the United States. And findings indicate that approximately 10 percent of women of childbearing age may already have dangerous levels of mercury in their bodies. If you are concerned, consult your doctor. Most labs can detect mercury levels by testing hair.
Mercury isn't the only issue: There are other toxins lurking in fish. Chemical pollutants such as PCBs and dioxins pose similar health threats including learning disabilities in children. Dioxins are an industrial byproduct that come from bleaching paper and incinerating wastes. Even though the most well-known of these chemicals—Agent Orange—was banned years ago, there are still a lot of dioxins that are being actively released into the environment. PCBs and dioxins are nonbiodegradable; thus, they contaminate rivers where they are used and can accumulate in fish. "Dioxin, for example, is a toxic chemical that has been linked to cancer, learning disorders and immune disorders," says Jeremiah Baumann, environmental health advocate for U.S. PIRG. "Like mercury, these toxins can be found at dangerous levels higher up in the food chain."
The Ecological Balance
There's another hook to eating fish: sustainability—the concept of catching or raising enough fish to eat without depleting a species or damaging the environment. If you're one of those "think globally, act locally" types, then it's likely the environmental impact of eating fish matters to you. Parts of the fishing industry are actually hurting the environment by overfishing certain species, and attempts to farm fish as an alternative can have detrimental environmental effects.
A 1999 report from the National Marine Fisheries Service in Silver Spring, Md., indicated that 98 species were overfished. In a summary from the Audubon Society, the overfished list included swordfish, shrimp, orange roughy, grouper, scallops and others.
And some wild-caught seafood can kill or injure other marine life. For example, for every pound of shrimp scooped out of the ocean, up to five pounds of other marine life can be damaged. Furthermore, some fish farms net local waterways to get feed for their fish. It can take up to three pounds of wild-caught fish to raise one pound of farm-raised salmon. And fish farms are often within or connected to a natural body of water and can discharge toxic waste into clean waters. Also, farmed fish aren't as strong or resilient as wild fish. "Escapees" can breed with and genetically weaken wild species.
In response to these problems, some organizations are trying to tighten the line on commercial fishing by certifying sustainable fisheries. The Marine Stewardship Council (MSC) in Seattle is one of those organizations (www.msc.org).
"We are trying to reward responsible fisheries that comply with our standards by issuing them our Ecolabel certification," says Karen Tarica, U.S. communications director for the MSC. "These are fisheries that are not overfishing or harming the marine ecosystem." Alaska salmon was the first U.S. seafood to be certified, and the list now includes Thames herring in the United Kingdom, Western Australia rock lobster and New Zealand hoki. More than two dozen fisheries are up for the certification process. EcoFish recently became MSC's first certified national distributor of retail fish.
The trend toward sustainable fishing is growing. According to Tarica, Unilever—the second-largest buyer of fish in the world—has committed to purchasing only MSC-certified fish by the year 2005. That means from an ecological point of view, the industry is on the right path. These actions may help address the environmental issue; however, it's still up to you to get savvy about toxicity.
What You Can Do
By now you're probably up to your gills in bad news. But don't worry; choosing safe-to-eat and environmentally friendly fish isn't so hard. Here are some suggestions. Focus on farm-raised trout or catfish, shrimp, flounder and wild-caught Pacific salmon, croaker, haddock and blue crab from the mid-Atlantic. According to the "Brain Food" report, these are species that pose a low mercury risk.
Avoid fish that are more likely to contain mercury including swordfish, shark, tuna, king mackerel and lobster. Limit canned tuna, and if you're not sure about a fish, don't eat it. To view the complete list, log on to www.ewg.org.
Check out the history of the water quality in the area, including vacation destinations, before indulging in a daily diet of fresh-caught fish. A list of state and local contacts on fish safety is available on the EPA's Web site at www.epa.gov/ost/fish/.
Choose EcoFish as a sustainable alternative. It's found in the frozen-fish section, sometimes in its own cooler. For more information, check out www.ecofish.com.
Shop in conscientious markets that include sustainability in their mission. Talk to the fish guy or gal; find out where their fish comes from and what their policies are.
By taking proactive steps and educating yourself, eating seafood can continue to provide oceans of pleasure.
Chris O'Brien is a freelance writer specializing in natural health.