On a recent cloudless afternoon, Croton Point Park seemed to be a fishing paradise. The tide was low; the breeze was soft. Families picnicked and people stood along the shore with fishing rods, casting out into the Hudson in hopes of catching and carrying away one of the river’s coveted bluefish or striped bass. The only problem — though it was invisible — was in the fish themselves.

“We’ve been coming here to get our fish for many years, and it’s been great,” said Miguel Tejada, holding a sleek fishing rod in his hands as his wife and two small children looked on. “I have heard people say that you should not eat the fish here too much, that the fish are not safe. But I’m not really worried.”

For years, state health officials have warned that because of mercury and PCB contamination, women of childbearing age and children under 15 should not eat any fish from the Hudson River, and other people should do so only sparingly. Studies and surveys have nonetheless found that many people are either unaware of those warnings or, like Mr. Tejada, simply ignore them.

But scientists are finding that the consequences for those who turn a blind eye are hard to overlook. An examination of 124 anglers at a half-dozen piers and fishing clubs along the lower Hudson River found that those who reported eating locally caught fish — about 80 percent of the group — had about twice as much mercury in their blood as the others, according to a recently released study.

That report is the first to document the levels of mercury in anglers who regularly get their meals from the lower Hudson, which the health department defines as south from the Rip Van Winkle Bridge near the town of Catskill. The study found that those who did so had an average of 2.2 nanograms per milliliter of mercury in their systems. That level is below the safe baseline of 5.8 nanograms per milliliter recommended by the Environmental Protection Agency, but still worrisome to scientists who say the health effects of long-term exposure to those levels of mercury are not well understood.

The report, by a team of researchers at the Mount Sinai School of Medicine, was published in the June issue of the journal Environmental Research. “This was an eye-opener for us,” said Anne L. Golden, an assistant professor in the Department of Community and Preventive Medicine who was involved in the study. “The knowledge level was high, but people were taking educated risks. They were still eating the fish they caught, and in quantities that definitely exceeded the recommended limits.”

The study showed that most anglers, including those who never eat local fish, shared their catches with family, friends and acquaintances. Perhaps most alarming was that nearly 40 percent said they gave locally caught fish to women of childbearing age. That is something scientists have warned against, because mercury and PCB can be stored in the body and passed on to children during pregnancy or while nursing.

When exposed to levels of mercury above the federal limit — and possibly even below it, some scientists argue — a fetus or an infant can suffer neurological damage. Since many people who eat local fish have at least some knowledge of the warnings, scientists and health officials have struggled to understand why so many people risk their health. The explanation may have something to do with the invisible nature of the threat, said Edward Horn, a senior scientist with the State Department of Health. People see the water, which looks clean; they see the fish, which look healthy, he said, so they think there is no danger.

“Any harm from eating the fish is not obvious,” Dr. Horn added. “In other words, people don’t get sick the next day. It’s not the kind of harm that is easily linked to what they do.” Mercury is released into the atmosphere largely by coal-fired power plants and by solid-waste incinerators. In the form of methylmercury, it drifts into lakes and rivers, where it is absorbed by fish and shellfish and gradually passed up the food chain.

Two of the types of fish in the Hudson that accumulate the highest concentrations of mercury, striped bass and bluefish, are also among the most popular among local anglers, surveys find. In detailed advisories over the years, the state has been warning most adults to eat those fish and others from the Hudson no more than once a month.

But getting the word out has not been easy. For a long time, one way the state distributed the warning was by including it in the packet that anglers receive when they buy fishing licenses. But a license is not required to fish the waters of the lower Hudson River, so many anglers never receive those pamphlets. “The further south you go down the Hudson, the more anglers you find without licenses,” Dr. Horn said.

The hurdles are also cultural. In Harlem and other popular fishing spots along the southern end of the Hudson, experts say, some of the anglers come from impoverished homes where it is more feasible to pull fish from the river than to buy them. Others are immigrants from the Caribbean and Central America, who say that fishing for food has always been a way of life for them.

Mr. Tejada, who lives in Tarrytown and is from Guatemala, regularly fishes at Croton Point Park. He said that he and many of his friends and relatives who also came to the United States from Guatemala learned to fish as children. “I’ve been fishing all my life,” said Mr. Tejada, who is 40. “And so has everyone in my family. It’s something we have always done together.”
(By Anahad O Connor, The New York Times ,19/08/2006)