Experts acknowledge that the level of ignorance is probably even higher among tourists, who visit Maine for brief periods of time and have less chance to read or hear about the warnings.

No one has suffered toxic effects from eating contaminated Maine fish, at least as far as state health officials know. But the risk is real, especially for pregnant women, fetuses and young children.

In a fetus and young child, mercury damages the central nervous system precisely while it is developing, controlling the ability to walk, talk, see, feel and use small muscles.

''If you have a high enough dose at the wrong period of time, you can interfere with that process,'' said Philip Kemp, assistant state toxicologist.

The mercury problem isn't going away. Mercury can persist in the atmosphere for years, and the amount falling from the air worldwide is rising. That means that - unless more is done to curb mercury pollution - warnings may become more stringent and widespread, not less so.

Worried about the lack of public awareness, a private conservation group last summer began its own, limited public-education campaign. The group posted signs at popular fishing spots between Brunswick and Augusta.

State health officials have mixed feelings about the postings. But they admit they should do a better job of warning the public.

''Unequivocally, yes, we need to do more,'' said Dr. Andrew Smith, the state toxicologist at the Maine Bureau of Health. ''What's not immediately clear right now is what the most effective ways are to get the message out.''

No concerted campaign

At left: The Friends of Merrymeeting Bay posted this fish consumption advisory notice to a telephone pole alongside Route 24 in Bowdoinham after deciding the state wasn't doing enough to warn anglers of the dangers of eating freshwater fish.

The advisory warns three groups of people - women who are or may become pregnant, nursing mothers and children under 8 - to eat no fish like bass, perch, sunfish or pickerel, which thrive in warmer inland waters.

Others should eat no more than two or three meals a month of warm-water fish.

For species like trout and salmon, which generally live in colder inland waters, the limits on how much to eat are higher. These fish generally contain less mercury than warm-water species.

The health bureau has tried in limited fashion to publicize the advisory, which also contains warnings for dioxin and PCBs - other toxins in Maine waters - by issuing press releases.

Copies of the advisory have been distributed at a major sportsmen's show and to the state's 1,200 registered dealers of fishing licenses.

The original 1994 advisory also is printed in the 70-page rule book the state fish and game department gives to anglers when they buy fishing licenses.

There has been no concerted education campaign, though, and it shows. Many people remain unaware of the warnings.

In a statewide telephone poll conducted for The Portland Newspapers in August, 60 percent of the people surveyed said they knew there were limits on how much freshwater fish they should eat from Maine lakes and ponds.

And even among those people who know of the advisory, 63 percent could not identify who the limits were designed to protect.

Only 3 percent knew a limit applied to nursing mothers; 4 percent said a limit applied to women of childbearing years; 6 percent mentioned children under 8 years of age; and 10 percent mentioned pregnant women.

The poll of 450 Maine residents was done by Strategic Marketing Services of Portland. The findings have a 5 percent margin of error at a confidence level of 95 percent. That means that if the poll was repeated 100 times, in 95 cases the results would be within 5 percent of the present findings.

Smith, the state toxicologist, said he was not surprised by the results of the newspaper poll because it surveyed the general public, rather than licensed fishermen, who are more likely to eat fish.

In a survey of licensed anglers conducted in 1994, two University of Maine researchers found that 76 percent knew a mercury advisory was in effect.

But they also found that more than half of the licensed female anglers under age 45 kept some of the fish they caught - presumably to eat.

At right: Federal biologists Drew Major, left, and Kenneth Munney pull 20 yellow perch from a gillnet set in Hunters Cove on Rangeley Lake. The 2- to 4-inch fish contained surprisingly high levels of mercury despite their young age.

Smith said the newspaper poll's finding that few people could identify pregnant women as a high-risk group was a disturbing statistic.

''This confirms again that the population we most want to reach, we're not reaching,'' he said. ''And that is pregnant women.''

Gov. Angus King agreed that the state should do a better job of publicizing the mercury advisories.

But he said the newspaper poll may be misleading because it surveyed the general public, including people who don't buy fishing licenses and theoretically are unlikely to eat freshwater fish.

''The more relevant question is the level of awareness among people who are most likely to eat fish,'' King said. ''Because it's not really relevant to those who don't.''

Developmental delays

As a neurotoxin, mercury attacks the brain and the central nervous system.

Children who are exposed in the womb usually appear normal at birth, but can experience delays in walking or talking. When mothers receive a very high dose, their children are more likely to have these developmental delays as well as other effects, such as mental retardation or cerebral palsy.

Many young children affected by mercury receive no treatment because years can pass before the symptoms are recognized.

In older children or adults, symptoms of mercury toxicity include numbness or tingling in the arms and legs; a loss of hearing, vision or memory; paralysis; emotional disturbances and kidney disease.

The most notorious mercury poisoning incident in history occurred in Minimata, Japan in the mid-1950s, when a chemical company dumped mercury into a bay where local people caught most of the seafood they ate.

Other public exposures occurred in Japan in 1965 and in Iraq in the early 1970s, when people made bread from seed grain that had been sprayed with methylmercury as a preservative and fungicide.

At left: Four-year-old Kaitlyn Marks watches her dad, Monty Marks of Augusta, cast his line into the Kennebec River in Augusta. Kaitlyn loves fish but never gets to eat any of the fish caught by her father. "It's all catch and release nowadays," he said.

By contrast, when the Department of Environmental Protection tested fish for mercury in 120 Maine lakes, the highest concentration was 2.5 parts per million - at Hodgdon Pond in Acadia National Park.

Even at such low levels, however, mercury in the fish can be harmful if too much fish is eaten, especially by pregnant women or nursing mothers.

Some anglers skeptical

Sharon Leeman of Palermo, who has been fishing for more than 30 years, said she regularly feeds her grandchildren white perch and has probably consumed 40 of the fish in the past two or three months.

White perch is a warm-water species that should not be eaten by children under 8, according to the state advisory.

Leeman, whose youngest grandchild is 3 years old, said she doesn't worry about the mercury because the children only eat two or three meals a month.

Leeman is skeptical of the advisory because she knows people in their 80s who have eaten fish all their lives without getting sick.

''We pay a lot of money just to be able to go fishing,'' she said. ''It's too bad something like this has to come up to spoil it.''

Others just don't understand the advisory or the issue of mercury pollution.

''I thought it was only a problem in southern Maine,'' said Phyllis Knott of Winterport, the wife of an avid bass fisherman.

At right: A poorly reproduced copy of the 1997 Maine fish consumption advisory is posted at knee level in the Route 95 Visitor's Center in Kittery.

''If they know it's so dangerous and there's so much of it, then I don't know why they don't do more about it,'' Anderson said.

Some critics say the mercury limits may be set too low. They say freshwater fish are less dangerous than government officials believe. They also question the science that went into deciding what levels of mercury in fish are safe and unsafe.

Researchers are studying fish-eating populations on islands in the North Atlantic and Indian oceans to learn more about how toxic mercury is to people. It is hoped the results of those studies will end the scientific uncertainty that surrounds this question: How much mercury for humans is too much?

Some Mainers who are concerned about mercury poisoning aren't waiting for more studies.

Last month, Friends of Merrymeeting Bay, an environmental group, posted warnings at popular fishing spots on the Kennebec and Androscoggin rivers and their tributaries near Bath, Brunswick and Augusta.

Steve Brooke, a volunteer who helped with the posting, said the group believes the public needs to know more about the warnings.

He raised another criticism: That the state, by issuing one set of advisories for Maine, was implying that mercury and other contamination levels are consistent statewide. Indeed, they are not.

Mercury levels can vary from region to region, and even from waterway to waterway. The same applies to contamination from dioxin, PCBs and other toxins.

''We felt the state's advisory was confusing because it was so statewide,'' Brooke said. ''There were some areas that clearly had more severe warnings than others, but you had to read the advisory with great care to understand that.''

Brooke said youngsters fish every day after school on the Kennebec River in Augusta, where a posting warns people to eat no fish because of contamination from dioxin and PCBs. The river also has a mercury advisory.

Smith, the state toxicologist, said posting along riverbanks and lake shores may be appropriate in areas where waters are so toxic that no one should eat any fish caught there.

But localized postings could create problems.

''What I worry about,'' Smith said, ''is that we may condition people into thinking it's OK to eat fish where there's no posting.''

Smith said other states also have found that people tear down posted warning signs, so they're not of much use over the long run.

Fish still beneficial

At left: Ten-year-old Lyndsay Bouchal of Newton, New Jersey casts her line into the clear waters of Sebec Lake. Bouchal and her father, Jerry, are typical of most visitors to the lake, reluctantly accepting that the fish are now considered toxic.

Another health issue crops up, however. Smith noted that, in general, it is good for people to eat more fish and avoid fattier meats in their diets. So he worries that a mass campaign warning about mercury in fish could scare people into eating less fish overall.

Increasingly, he said, public health officials are being asked to provide perspective by weighing the relative risks and benefits of certain kinds of behavior.

''That's going to be the big challenge in the whole area of fish consumption advisories nationally over the next few years,'' he said.

Some biologists are trying a different tack. They have started keying in on lakes near some of Maine's major mercury sources - especially those near HoltraChem Manufacturing, a plant in Orrington that uses mercury to make chlorine gas.

Their goal is to find out whether fish consumption advisories for the streams and rivers near HoltraChem are strict enough. Findings of high mercury levels also could be used to force the plant to reduce or eliminate its mercury releases.

Results of the current testing near Orrington are expected next year.

While the state moves ahead with its work on mercury, Mainers and tourists will continue to flock to Sebec Lake and other fishing spots.

On a warm day in August, as eagles and ospreys soared over the lake, people motored out to Bucks Cove, flicking their fishing lures into the cool green waters, hoping to land a nice perch, bass or trout.

Bouchal, the New Jersey resident who ate fish from Sebec Lake with his daughter, Lyndsay, said the advisory won't keep him from Maine.

Nor will it stop Benjamin St. George, who brings his wife, children and father up every summer from Chicopee, Mass.

''For the short amount of time that we're here, I don't think it's that much of a concern,'' he said.

Peg Lusardi of Raritan, N.J., agreed. ''I don't think we're ladening ourselves down with mercury because we're not big fish-eaters anyway.''

Jerry Packard, whose family established the sporting camps on Sebec Lake 103 years ago, said the popularity of catch-and-release fishing also helps eliminate the health problem for many of his guests.

Most others, he said, assume they won't be eating enough fish to do any harm.

Still, as time goes by, he finds himself being questioned about the warnings by a rising number of his guests.

''I'm not sure what to tell them,'' Packard said.

Mark Sullivan, the congressman's press secretary, said Monday that Allen, a Democrat, plans to lead a discussion of the issue under a special order within 10 days.

A special order allows members to introduce issues not regularly scheduled on the House calendar.

Sullivan said graphics and photographs from the newspapers' series will be used on the House floor to illustrate Allen's discussion.

Allen also plans to introduce the series, which began Sunday and continues through Wednesday, into the Congressional Record.

''He wants to use the material as a vital part of the presentation to raise public awareness of the issue,'' Sullivan said. ''The series gives us an opportunity to do that on a national basis.''

Allen supported a ban on the use of mercury in batteries when he ran for Congress in 1996.

After he was interviewed for the mercury series last summer, Allen endorsed a House resolution by Rep. Bernard Sanders, I-Vt., calling for the release of a vital U.S. Environmental Protection Agency report on mercury.

Sanders will participate in Allen's presentation, Sullivan said.

- Dieter Bradbury