It was conceived as a sanctuary, a "celestial community" where people of modest means could afford to buy a house and escape from crime and pollution and the other problems of the world.

But Christian City, as the little Pentecostal enclave is called, has been visited by mercury contamination, one of the worst plagues of the industrial age. Its houses, now overgrown by weeds, stand like tombstones marking environmental disaster. A narrow creek skirting the settlement carried toxic wastes from factories upstream, exposing about 1,200 residents to the poisonous detritus of progress.

Christian City was evacuated last year by Puerto Rican authorities. It was the first time an entire community in North America is known to have been endangered by mercury pollution, a public health threat reminiscent of the mercury poisoning nightmare of Minamata, Japan, 30 years ago.

A baby girl, born deformed, died a few hours after birth, and the attending doctor listed "Minamata disease" in his final diagnosis. Two-thirds of Christian City's inhabitants who have had their blood tested showed abnormally high levels of mercury, as much as six times the U.S. norm. They still complain of the chronic effects of the quicksilver that lodges in body tissue and takes a long time to expel: skin rashes, insomnia, muscle tremors, memory loss, depression, loss of balance, oral bleeding, headaches, loose teeth and vomiting.

Now living in temporary, government-subsidized housing, the refugees of Christian City are shunned like social lepers. They have lost jobs and friends, who mistakenly believe the disease is contagious. In public buses, shops and work places, others keep their distance.

"Not even in the Bible is there a hell as bad as this," Elizabeth Algarin said, weeping as she described her physical and mental deterioration in five years at Christian City. "Friends who see me say I no longer look like the same person."

The story of Christian City is so tangled in local political infighting, legal maneuvers and disputes between Puerto Rican and U.S. federal agencies that it is impossible to establish indisputably either the extent of mercury poisoning or its source.

No one questions, however, that mercury has seriously polluted the Frontier Creek, which snakes through the Humacao Industrial Park and flanks the once utopian community.

Former residents contend that two of the industries -- Squibb Manufacturing Inc. and Technicon Corp. -- discharged mercury wastes into the creek; that the developer of Christian City dredged it and used tons of the contaminated earth to fill in the marshy land on which houses were built, and that hundreds of people got sick from breathing mercury vapors, gardening in mercury-laden topsoil and eating mercury-tainted fish.

All of this was tolerated, they contend, by local officials bent on economic growth and federal officials too myopic to recognize the long-term danger of mercury pollution. Puerto Rico, a commonwealth associated with the United States, elects local officials but is governed by federal law.

"It is against Christian and natural law to have treated these human beings as objects," said Jose Grau, a Humacao lawyer representing the dispossessed and largely poor evacuees.Official Circumspection

Officials of the U.S. Environmental Protection Agency and the Centers for Disease Control acknowledge that the creek is contaminated. But they say there is no evidence that the pollutant spread to the residents and homes of Christian City or that mercury posed an "immediate and significant health threat."

"It's been blown out of proportion," said Dr. Mary Mortensen, a CDC medical officer. "We took a great deal of time and effort to look at this case. There really wasn't the evidence to support evacuation."

Officials of the Squibb pharmaceutical company denied the charge of dumping mercury, claiming no mercury has ever been used at the Humacao plant.

A spokesman for Technicon, which manufactures medical diagnostic equipment, declined to comment when asked whether the factory has ever used mercury or dumped it into the creek.

The developer, Morris Demel of San Juan, said that while he had the creek dredged to reduce the risk of flooding the community, the excess dirt was unloaded on the Frontier's banks, not on the swampy foundation of Christian City.

The horrible effect of mercury poisoning has scarred the world's memory since the epidemic of maiming and death afflicted the fishing town of Minamata in 1956. Cats went mad, hurling themselves into the sea, and children were born blind and brain-damaged from the scourge, which was eventually linked to mercury wastes dumped by a chemical factory.

Although American workers exposed to the silvery metal have suffered mild health symptoms, mercury is not known to have caused a public health problem in the United States.

Rey Figueroa, an evangelical minister, founded Christian City in the late 1970s and promoted it as a "celestial community" removed from crime, alcohol, gambling and prostitution. The houses ranged in price from $28,000 to $38,000 and came in several models.

The settlement was sited on 700 acres of Humacao, a former sugar cane center that turned into a light industrial town of 50,000 on the east coast of Puerto Rico, 35 miles from San Juan.

Puerto Rico's New Progressive Party came to power in 1977 and viewed Figueroa as a key political ally who could dilute the opposing party's traditional strength in Humacao. The commonwealth's development agency financed construction of Christian City, a low-cost housing project originally planned for 3,000 units.

By late 1979, the first families moved into the one-level, cinderblock structures set in straight rows like typewriter keys. On all sides were low mountains and lush, emerald wetlands where cattle grazed.

Health troubles were noticeable a year after arrival for many residents. Their heads throbbed, their throats burned, their skin broke into rashes and boils. Good students began falling asleep in class. Women who previously had easy pregnancies began to miscarry.

Complaints of dizziness, weight loss, numbness in extremities and coordination problems became common. Adults set out from their homes only to forget their destination midway through the journey. Sleepless, anxious family members had violent quarrels for the first time.

Their doctors had no answers.

"I had headaches like I was going out of my mind, I felt like ants were crawling all over me. I was desperate," recalled Josefa Solis, 70, who entered Christian City in 1981. "Then, my hair started falling out and my teeth fell out just by touching them. All my teeth."

Carmen Diaz, 45, who moved in in 1979, said her nerves were so frayed that she had to quit her job as a school lunchroom attendant because "I'd get hysterical from the children's noises and I'd drop the food trays." 'Another Love Canal'

Residents thought at the time that their ailments may have had something to do with the pungent odor coming from the industrial park less than 500 yards north of Christian City's front gate. But no one connected the epidemic to the opaque, lazy Frontier Creek, until Bethsaida Rivera got angry.

Rivera, now 30, had been living in Christian City with her husband and two children since 1980. As the health of her family deteriorated, she began lobbying Puerto Rico's Environmental Quality Board for help. In early 1984, an EQB official told her that fish caught in the Frontier in 1979 had been found laden with mercury.

Frontier Creek, a popular fishing hole that regularly overflowed into pastureland and drained into natural lagoons, had been polluted for years.

"I knew at the time that we had another Love Canal," said Rivera, referring to the toxic waste dump in Niagara Falls, N.Y., considered so dangerous that 940 families were evacuated in the late 1970s. "I said Christian City is going to be a ghost town."

Rivera passed on the information to a local legislator, who already had launched an investigation of Christian City's problems. The probe revealed that the Frontier had been an open sewer for Christian City's industrial neighbors from the early 1970s to 1979 when the companies hooked into a municipal treatment plant.

Technicon had been cited by the EQB in September 1978 for dumping mercury and other toxic wastes. The firm, based in Tarrytown, N.Y., paid $125,000 to settle the case. A spokesman said recently that the company never acknowledged wrongdoing in the settlement.

In November 1984, the New Progressive Party, embarrassed by the Christian City imbroglio, was voted out of office. The incoming governor from the Popular Democratic Party quickly turned his attention to the mercury problem, directing the EQB to test the creek and community for evidence of the hazardous heavy metal. New Governor's Study

The results, reported in early 1985, revealed that:

Twelve soil samples from the banks of Frontier creek contained mercury levels as high as 17 times the average concentration in U.S. soil.

Of 14 samples of the Frontier's sediment, seven collected from the bottom of the creek as it flowed past the industrial park contained mercury levels as high as 100 times the average for U.S. estuarine sediment. Levels in seven samples taken from the creek upstream of the factories, however, ranged from undetectable to three times the U.S. average.

Sixty-five dirt samples from residential yards in Christian City contained mercury levels as high as 30 times the average concentration in U.S. soil.

The environmental findings provided an intriguing clue to Humacao doctors, who had run out of hypotheses for diagnosing the health problems of Christian City residents. Now the physicians had a new scenario -- mercury poisoning -- and, in early 1985, they began sending blood samples to laboratories in Chicago, Florida and New Jersey.

Of 212 samples, 63.2 percent came back showing mercury concentrations higher than normal. Such high levels usually signify mercury "intoxication," a term used to describe the behavior changes of contaminated people.

"What I have seen in Christian City are chronic mercury intoxication cases," said Dr. William Marquez, who has more than 100 patients from the community. "Some of these people are very sick. I don't expect anybody to die. But I expect them to be miserable for a very long time."

Martha Rijes lived there from 1983 to the day of evacuation, and she lived to regret it. In June 1984, she became pregnant. It was a difficult pregnancy, she said, because of the daily headaches and the boils she developed under her arms and on her eyelids. And, she never felt the baby moving, even in her eighth month.

A 3-pound baby girl arrived eight weeks early. Her ears were abnormally placed, her left hand was missing a finger and her feet were as flat and flexible as rubber swim fins, said Rijes.

Two hours later, the baby died. The hospital doctor said, "Your baby looked like a mummy," Rijes recalled in an interview. On the hospital record, he noted Minamata disease and "interuterine growth retardation due to mercury intoxication."

An autopsy report confirmed the abnormalities and added that the baby's kidneys, bladder, lungs and reproductive organs were undeveloped. An analysis of the placenta and the baby's liver, blood and brain showed concentrations of mercury.

"I'll never have a baby because of the mercury in me," said Rijes, 23, nervously fingering color photographs of her baby. "They'll come out deformed. I feel like E.T. or somebody from outer space. They poisoned me and my baby."

Alma Torres, 33, had three healthy children before moving into Christian City in 1980. Her husband, Louis Torres, 31, affectionately called her a baby "factory" because of her fertility and effortless pregnancies.

Over the next four years, however, Alma Torres had three miscarriages. Her pregnancies, none of which lasted for more than four months, were complicated by high fevers, cramps, vomiting and heavy bleeding. She had her blood tested, and the results showed mercury levels more than three times higher than normal.

"We had to close down the factory," said Louis Torres, an industrial mechanic who works for Squibb. "We have no choice. I'm afraid to try again."Analytical Questions

Whether these health problems were caused by mercury contamination is a matter of debate. Federal officials ruled out any "immediate and significant health threat" last summer after analyzing soil samples from Christian City yards and finding their mercury levels significantly lower than the EQB test results. Privately, they question the methodology of the Puerto Rican tests.

"The evacuees are in limbo and are understandably frustrated and upset," said EPA spokesman James Marshall.

Commonwealth officials dismiss the EPA soil tests for failing to dig deeper than three inches -- compared with six inches by the EQB -- to measure a heavy metal that bores deeply into the ground.

Federal officials have not performed medical examinations of the Christian City population. Mortensen, the CDC toxicologist, said the high blood levels of mercury reported by private U.S. laboratories bear closer scrutiny. But she noted that many of the symptoms linked to mercury here could be caused by anxiety.

Demel, the developer, was blunter in his evaluation. "Not a one" is sick, he held in an interview. The ailments, he suggested, may be a product of mass hysteria or a pretext of residents who wanted to leave homes they could no longer afford.

To skeptics, Puerto Rican officials cite follow-up tests by the commonweath health department, which found abnormally high mercury levels in the urine, hair and blood of some residents. A panel of local physicians analyzed the results and concluded that "there is evidence of mercury contamination" among those tested.

Christian City has been abandoned for more than a year, many of its 480 units stripped by vandals of their toilets, stoves and sinks. The rusted hulk of an old Chevrolet, sprouting weeds from the driver's seat, sits on cinder blocks, a singular reminder of human habitation. Cows from neighboring fields laze in the shade of empty carports, and the only sound is the croak of frogs.

The exiles of Christian City have been placed in rent-free housing while the banks, the courts and the government haggle over questions of mortgage payments and property loss.

Still, the social stigma of mercury contamination haunts them. Their names and faces have been widely circulated by the local news media. Their children are taunted by schoolmates who have been warned by their parents to stay away from "the mercurians." Passengers have refused to ride in a public bus whose driver had passed through the settlement.

"It's like living dead," said Rivera. "We feel so different from everybody else. We want to feel like human beings again, that we're not going to be deprived of life's joys.