AS its name suggests, Midway atoll in the North Pacific is a long way from anywhere: 3,100 miles from Los Angeles, 2,400 miles from Tokyo and 1,150 miles from Honolulu at the other end of the Hawaiian Islands chain. But isolation has not protected oceanic birds nesting on Midway from environmental contaminants that originate in distant places. Researchers have found high levels of DDT compounds, PCB's and dioxin-like compounds in black-footed albatross adults, chicks and eggs.

They have also found the telltale effects of exposure to these chemicals, which remain in the environment a long time. Among those effects are deformed embryos, eggshell thinning and what the researchers say is a 3 percent drop in nest productivity. The results are cause for concern because of the potential for greater harm to albatrosses and other species. PCB's and dioxin-like compounds have caused embryo deaths and chick deformities like crossed bills and club feet in double-crested cormorants, Caspian terns and other fish-eating birds that nest in Great Lakes colonies. The pesticide DDT and its breakdown product DDE gained notoriety 30 years ago in North America when they were blamed for collapsed eggshells that led to population crashes in birds like bald eagles, brown pelicans and peregrine falcons.

One of the researchers, Dr. Paul Jones, an environmental chemist in New Zealand, has a paper that is to be published in Environmental Toxicology and Chemistry on the Midway albatrosses. And Dr. James P. Ludwig, the head of the research team, presented an abstract of his findings at a recent meeting of the American Chemical Society in Honolulu.

"If these findings were seen in the Great Lakes they would not be unexpected," said Dr. John McLachlan, director of the Tulane-Xavier Center for Bioenvironmental Research. "Coming in the middle of the Pacific Ocean makes them all the more dramatic, and I think these observations are potentially very important."

"Concentrations of persistent chemicals in black-footed albatrosses on Midway are nearly as great as current levels in bald eagles from the highly contaminated Great Lakes," said Dr. Ludwig, a bird population ecologist. Laysan albatrosses, which also breed on Midway, have a significantly lower toxic burden in their blood and eggs, and scientists attribute this to the two species' different feeding habits.

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Dr. Ludwig, who led an international research team to the atoll, said the pollutants in the birds' diet were probably coming from India, Southeast Asia and Japan. The discovery came as a surprise, since there was no previous evidence to suggest that high levels of toxic chemicals occurred in seabirds in remote tropical ocean areas. "We chose the Midway albatrosses as representative of a relatively pristine environment," said Dr. Rosalind Rolland, a conservation scientist at the World Wildlife Fund in Washington. The organization sponsored the project with financing from the United States Environmental Protection Agency, but the study was halted last year because of budget cuts at the agency, canceling a final season of field work and delaying publication .

A member of the Midway team, Dr. John Giesy, a toxicologist at Michigan State University, said: "While albatrosses feed near the top of the food chain, they forage on the open ocean far from continental pollution sources, and we expected to find very low contaminant levels. Our research demonstrates that global controls on the distribution of persistent, bioaccumulative toxic compounds need to be considered. The problem can't be approached on a country-by-country basis."

Black-footed albatross nest productivity on Midway has been reduced by about 3 percent because of the contaminants, Dr. Giesy said. So far this effect is nowhere nearly as serious as the accidental deaths of thousands of adult albatrosses in fishing nets. Nearly 4,500 black-footed albatrosses were killed in drift nets in 1990. "Albatrosses are long-lived birds, and the loss of a young female that could breed for another 30 years is more meaningful than an unhatched egg," Dr. Giesy said.

Dr. Giesy noted, however, that concentrations of PCB's and dioxin-like chemicals in black-footed albatross eggs were at a threshold where further deposits would be expected to cause adverse population-level effects. "This is especially true because a very small increment in the toxic dose can cause a steep response," Dr. Giesy explained.

Dr. Ludwig said that amounts of DDT compounds in black-footed albatross eggs were running just under two parts per million. "These are not trivial amounts when you consider that eggshell thinning in a number of birds has been shown to occur at levels of between two and three parts per million," he said. "We looked at 4,000 albatross eggs, and crushing at the pointed end appeared to be the cause of two-thirds of the unhatched eggs. The effect of eggshell thinning is very slight from a population perspective, but it's a warning that we shouldn't put any more of this stuff out there. And there's no guarantee that the black-footed albatross is the most sensitive species."

Albatrosses are good birds to study, the scientists said, because they live for 40 years or longer, mate for life, return year after year to the same nest and have no fear of humans. Most of the 14 species nest on islands in the Southern Hemisphere and during the nonbreeding season, they wander the southern oceans for months without once coming to land.

But the black-footed and Laysan albatrosses breed mainly on outlying atolls and islets in the Hawaiian archipelago, and they roam North Pacific waters as far as Alaska, California, Taiwan and the Bering Sea on wings that span six to seven feet.

The worldwide population of black-footed albatrosses is estimated at 100,000 birds, Laysan albatross population at about 2.5 million. The two small islands at Midway atoll, Eastern and Sand, have a total land area of only two square miles but they support 7,000 nesting pairs of black-footed albatrosses and 200,000 pairs of Laysan albatrosses.

North Pacific albatross colonies were decimated by Japanese feather hunters early in this century, when 300,000 birds were slaughtered in one year on Laysan Island alone and colonies on Wake, Johnston and other islands were wiped out. The Midway colony recovered from the depredations of hunters by the end of World War II, but 54,000 adult albatrosses were killed by United States Navy personnel from 1955 to 1964 to reduce bird-plane collisions at a military air base on Sand Island, and black-footed albatross numbers on the atoll never returned to their 1945 level. The air base is now largely inactive.

Each albatross pair raises a single chick, which is fed partly digested fish and squid along with fat-rich oil from the stomach of parent birds that often forage several days' flying time from the nest. Albatrosses typically feed by sitting on the water and seizing prey on the surface. Flying-fish eggs floating on the surface are the main part of the black-footed albatross diet, but the birds also snatch flying fish as they flit past.

Laysan albatrosses, however, feed heavily on squid, which rise to the ocean surface at night. Concentrations of toxic chemicals are magnified in animals that are higher on the food chain, and Dr. Ludwig said that flying fish were half a trophic level higher than squid.

"This accounts for the higher levels of contaminants in the black-footed albatross," he said.

The use of DDT has been banned since the mid-1970's in the United States, Canada and Western Europe. But Dr. Ludwig, who heads an ecological consulting group in Victoria, British Columbia, said it was still the chemical of choice for control of mosquitoes and crop pests in developing countries. "There is a large, fresh DDT plume coming off the coast of Southeast Asia and currents are carrying it into the north-central Pacific, where the albatrosses intercept it," he said. "This is not old stuff that's been around for 20 years. The half-life of DDT is about three years, and the ratio of the parent compound to the breakdown product DDE in blood samples of adult albatrosses is about 1 to 1."

One likely source of the dioxin-like compounds, Dr. Ludwig said, is the large amount of partly burned plastic ingested by albatrosses. The birds are notorious for swallowing floating plastic debris, and virtually all of the plastic items found in Midway albatrosses originated in trash dumped on the coast of Japan and other Pacific Rim countries, he said.

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