swordfish has high mercury levels
Store-bought swordfish contained mercury levels above the legal limit in a study released Thursday by environmental groups.
A University of North Carolina Lab found elevated mercury concentrations in 24 swordfish samples from supermarket chains including Safeway, Shaws, Albertsons and Whole Foods.
Groups that paid for the analysis want supermarkets to post signs warning shoppers of health risks from mercury, and they want the government to increase its testing.
"Americans have a right to know what's in their food, and posting warning signs in grocery stores where these fish are sold is a simple, commonsense solution that fulfills that right," said Jackie Savitz of the advocacy group Oceana.
The federal government advises pregnant women, nursing mothers and young children to avoid fish with high levels of mercury — shark, swordfish, king mackerel or tilefish. Elevated mercury levels have been linked to learning disabilities and developmental delays in children and to heart, nervous system and kidney damage in adults.
A supermarket industry group said it was not surprised by the survey, because swordfish and tuna are known to have higher levels of mercury. Many stores already offer brochures or have signs, the group said.
"The issue of asking for supermarkets to provide information at the store level is something companies are either engaged in doing or in the process of doing," said Karen Brown, senior vice president of the Food Marketing Institute. "Certainly, we would support that. We also would not be opposed to increased testing by FDA."
Average levels were 1.1 parts per million, just over the government's limit of 1.0 ppm. The Food and Drug Administration can take legal action to remove a product from the market if mercury levels exceed that limit. Two samples, from Maine and Rhode Island, contained double the federal limit for mercury.
Traces of mercury are found in nearly all fish and shellfish. Released through industrial pollution, mercury falls and accumulates in streams and oceans as methylmercury. Methylmercury builds up in fish and shellfish as they feed, in some types more than others.
However, eating fish also has widely acknowledged health benefits. The American Heart Association advises people to eat fish at least twice a week.
FDA and EPA advise even at-risk people to eat up to 12 ounces — about two meals a week — of fish and shellfish that are lower in mercury, such as shrimp, salmon, pollock, catfish and canned light tuna. FDA says to limit albacore, or "white," tuna to one meal per week because it contains higher levels of mercury.
Of 31 tuna steaks sampled, mercury levels averaged 0.33 ppm, a level comparable to that of canned albacore tuna.
mercury levels of fish
For now, a review of FDA's mercury measurements in 39 seafood varieties shows:
_Salmon, oysters, whitefish, sea bass, freshwater trout and sardines contain both high levels of heart-healthy omega-3s and low mercury levels, below 0.13 parts per million.
_Other low-mercury choices include perch, king crab, flounder, sole, pollock, catfish, croaker, scallops, crawfish, shrimp, clams and tilapia. They contain less omega-3s, but servings can add up.
_Tuna is controversial, because different varieties contain different amounts of both mercury and heart-healthy fats. Canned light tuna contains a small amount of omega-3, about as much as shrimp, and fairly low 0.13 ppm mercury. But fresh tuna steaks and the more expensive canned white or albacore tuna contain three times as much mercury, and almost as much omega-3 as salmon.
That puts albacore in the medium-mercury range. So many consumer groups recommend that pregnant women and children stick to modest amounts of the lower-mercury light tuna — about 9 ounces a week for women and 3 ounces for youngsters.
_Also in the medium-mercury range are saltwater trout, bluefish, lobster, halibut, haddock, snapper and crabs. Grouper and orange roughy are at the high end of this group. FDA's advisers said women of childbearing age probably should limit these fish to a serving a week.
_The FDA advises women of childbearing age to avoid shark, swordfish, king mackerel and tilefish, which contain the most mercury of species tested to date.
Study Records Elevated Mercury
Sun Oct 20, 6:35 PM ET
By SHARON L. CRENSON, AP National Writer
BURLINGTON, Vt. (AP) - A study of Californians who loaded their lunch and dinner menus with fish shows 89 percent wound up with elevated mercury levels in their bodies.
The research, presented Saturday by San Francisco internist Dr. Jane Hightower at a symposium of environmental health experts in Vermont, is one of the first studies to document mercury levels in Americans who eat more fish than the Environmental Protection Agency (news - web sites) recommends.
Doctors are increasingly interested in the possible risks of eating too much mercury-tainted fish, and the Environmental Protection Agency and the Food and Drug Administration (news - web sites) are trying to better inform the public about the subject.
It is a thorny problem because of the widely recognized benefits of fish, a high quality protein source loaded with heart-protecting Omega 3 fatty acids.
Conference participants didn't seem panicked about the findings: The majority ordered salmon for dinner Saturday — though salmon is considered among the safest types of fish to eat.
"We are not talking about whether or not to eat fish," said the EPA's Kathryn Mahaffey, one of the conference organizers.
Hightower screened 720 patients from March 2000 to March 2001, then tested the mercury levels of patients who reported eating more than two servings of fish a week. That's the maximum the EPA recommends for pregnant women and small children.
The tests showed that of 116 patients who had their blood tested, 89 percent showed mercury levels greater than the 5 parts per million recognized as safe by the National Academy of Sciences (news - web sites).
Of that group, 63 people had blood mercury levels more than twice the recommended level and 19 showed blood mercury levels four times the level considered safe. Four people had mercury levels 10 times as high as the government recommends.
The peer-reviewed study is slated for publication Nov. 1 in the journal Environmental Health Perspectives.
The study monitored 67 patients as they reduced their fish intake and subsequently their bodies' mercury levels. Within 41 weeks, all but two had reduced their blood mercury levels to below government-recommended thresholds, according to Hightower.
The study did not address physical symptoms such as fatigue or memory loss associated with mercury poisoning. Some patients did report such problems, but Hightower's study did not seek to correlate symptoms with mercury levels.
Still, Alan Stern, a New Jersey public health official at the conference, said any mercury study focusing on people who eat a lot of fish is a sort of "holy grail" for the field.
Too much mercury damages the nervous system, especially in children and fetuses, but scientists are not certain how much mercury-tainted fish is needed to trigger health problems.
The FDA currently recommends that pregnant women and young children limit their fish intake to two 6-ounce cans of tuna per week if it's the only fish they eat, and to one can per week if they also eat other fish. The agency says they should not eat any swordfish, shark, king mackerel or tilefish.
About 78 percent of patients with high mercury levels reported eating canned tuna more than three times a month; 74 percent ate salmon more than four times a month; and 72 percent said they had swordfish more than once a month. Other fish commonly eaten by the patients included halibut, ahi, sea bass and sushi.
Hightower recommended that doctors concerned about patients' mercury exposure take dietary histories including fish consumption to help identify people at risk of accumulating too much mercury.
She also recommended that state and federal government agencies make the results of mercury testing in fish available wherever fish are sold, along with the details of consumption advisories.
Mercury is a naturally occurring element that makes its way into the environment when oil- and coal-fired power plants burn those fossil fuels. Rain washes it into waterways, where it settles and is eaten by microorganisms, which are eaten by fish.
The Vermont conference was organized by the American Fisheries Society and the EPA.
