WASHINGTON -- A government study has found the cancer-causing chemical dioxin to be "at levels of concern" in fish caught downstream of numerous paper mills across the country.
Although the Westvaco Corp. mill at Luke, in Western Maryland, was rated the country's 36th-worst dioxin polluter out of 104 pulp and paper plants using the chemical in the paper bleaching process, Maryland was not a state where pollution caused the most concern.
Environmental authorities called on 11 other states with the 20 most-polluting mills to issue fish consumption notices or continuously monitor dioxin discharges into rivers.
Fish caught downstream of the Luke plant contained enough dioxin to pose a cancer risk to three out of every 100,000 people, said Henry Habicht, deputy administrator of the Environmental Protection Agency,
An International Paper Co. mill in Georgetown, S.C., was found to be the worst polluter, with fish posing a risk of one in 50 people. Two Virginia mills -- Union Camp Corp.'s Franklin plant (one in 500 risk) and Westvaco Corp.'s Covington operation (one in 1,000 risk) were among the 20 top contributors to health-threatening fish.
"EPA suggests that states consider imposing fish consumption advisories or start site-specific monitoring at all streams that have a projected risk as high as one in 10,000 or greater," Mr. Habicht said.
The EPA report, based on a study done in 1988, drew environmental groups' criticism.
"We think the EPA's method for estimating human health risks greatly understates the actual risks," said Jessica Landman, senior project attorney for the Washington-based Natural Resources Defense Council.
The agency's projected risks underestimated the amount of fish people eat and the rate at which the poisons build up inside fish tissue before it is eaten, she said.
"But even with these underestimates, the EPA study shows that people are at great risk if they eat their downstream catch," she said.
EPA spokesman Sean McElheny said the risks of cancer were calculated on an average consumption of about a quarter-ounce a day over a lifetime -- the equivalent of two quarter-pound fish meals a month.
He stressed, however, that sport fishermen or people who eat fish as a staple diet were at a considerably greater risk -- in the case of the Luke plant, for example, up to 1 cancer in 10,000.
In the case of the 20 worst polluters, including the mills in Virginia and South Carolina, dioxin levels were high enough to cause not only cancer but also liver failure and reproductive diseases, he said.
The NRDC also criticized the EPA for approving dioxin-discharge levels for Maryland last week 100 times higher than the agency's guideline of 0.013 parts per quadrillion.