No surprise there, but here's one. Eating fish is hazardous to your health.
sfgate.com
Try not to consume more than 38.5 micrograms of mercury per week...
SAN FRANCISCO -- A physician's examination of her well-to-do patients' fish-eating habits revealed nearly all of those studied had concentrations of mercury exceeding U.S. safety levels, making their health conscious diets appear a little less so.
Dr. Jane Hightower, a doctor of internal medicine at California Pacific Medical Center, looked at the diets of 89 middle- and upper-income patients for her evaluation, after selecting them from a larger group of 123 patients tested and 720 patients screened for testing.
Of those who dined on swordfish and ahi tuna steaks, 89 percent of them had blood-mercury levels exceeding the amount deemed safe -- 5 parts per billion -- by the Environmental Protection Agency and the National Academy of Sciences.
"They think they're doing the right thing by eating swordfish, sea bass, halibut and ahi tuna steaks," Hightower said of her patient base, made up of CEOs, lawyers and Internet company executives. "But they just happen to have the highest content of mercury sold in restaurants and grocery stores."
Hightower's findings were published in the current issue of Environmental Health Perspectives, a peer-reviewed journal published by the National Institutes of Health. Included in the results from the 89 people studied:
* 63 people had blood-mercury levels more than twice the recommended level.
* 19 people had four times the level considered safe.
* Four people had blood-mercury levels 10 times higher than the government recommended level.
* Each of the six children studied who ate fish as part of their diet had too much mercury.
Mercury is introduced into the fish food chain as air and water contaminants from mines, power plants and solid-waste incinerators.
The study did not compare mercury levels in fish eaters and those who do not eat fish as part of their diets. The study also did not attempt to correlate mercury levels with symptoms.
Kathryn Mahaffey, director of the EPA's Exposure Assessment Coordination and Policy, called the study important nonetheless.
Mahaffey said it has been known that some ethnic groups eat more fish than others.
"But we thought there was another group of urban consumers who would have unusually high mercury exposures because they subsist on fish and aren't limited by income, and choose a large proportion of their protein from fish because of taste preference or pursuit of health benefits," Mahaffey said.
Hightower said the health benefits from eating fish come from consuming fatty fish.
"Fatty fish is not swordfish or tuna. Fatty fish is like salmon or trout, sardines, those kinds of fish," Hightower said. "Like Wild Alaskan salmon. Their numbers on parts per million run probably about anywhere from 75 to 100 times less than a swordfish steak in mercury content."
According to the National Academy of Sciences and the EPA, a 120-pound person shouldn't consume more than 38.5 micrograms of mercury per week. According to the U.S. Food and Drug Administration, six ounces fresh tuna contains 68 micrograms of mercury, six ounces of canned albacore tuna contains 35 micrograms, six ounces of swordfish contains 170 micrograms, while six ounces of salmon contains only 6.46 micrograms. |
