THE ACREAGE, Fla. (The New York Times News Service) -- Stinging from news that a cluster of childhood brain cancer cases exists in their community, Acreage residents reacted with a range of emotions -- some determined to flee their homes, others saying they aren't worried about staying in an area where they have lived for years.

Meanwhile, U.S. Sen. Bill Nelson and other lawmakers are calling for a probe -- perhaps on the federal level -- into the cause. And one environmental expert said the cluster appears unusual enough to deserve national attention.

Resident Nancy Cook, a pediatric nurse who has lived in The Acreage for a decade, said she cried Monday when she heard the news that health officials had found a cluster. Then she called her mother in Lake Worth and asked if she, her husband and her four children could move in.

Cook said she is considering leaving The Acreage because health officials can't explain what's causing the problem and might not ever be able to.

"Without knowing the cause, how are you going to feel safe at night putting your kids to bed?" Cook said.

But longtime Acreage resident and activist Patricia Curry said she doesn't plan to leave the home she's lived in since 1980, despite some residents' suspicions that the cause may lie in the community's well water.

"I'm not afraid," Curry said. "I drink the water. My whole family drinks the water, and we're fine."

The state Department of Health is in its second phase of studying the cluster, an investigation it launched in June. On Monday it confirmed preliminary findings that the number of brain and central nervous system tumors and cancer in Acreage children is higher than it should be, especially among girls.

Authorities have identified 13 cases of brain cancer or tumors among children and teenagers in the community from 1993 to 2008.

Dr. Alina Alonso, director of the Palm Beach County Health Department, said that it's unlikely that health officials will be able to identify what has caused the jump, even after they analyze in-depth interviews recently completed with families whose children have been affected.

Nor are health officials planning to conduct environmental tests at this point, Alonso said.

That didn't sit well with federal, state and county legislators.

Nelson said environmental tests should start "as soon as possible." He pledged to work with the U.S. Environmental Protection Agency and the federal Centers for Disease Control and Prevention to get them to "lend their resources and expertise to the investigation."

"Residents still don't know a cause or what's responsible for these cases of cancer," Nelson wrote to Florida's surgeon general on Tuesday. "And we can't work to fix the problem or hold someone accountable, until we can answer these questions."

State Rep. Joseph Abruzzo, D-Wellington, rejected health officials' prediction that they probably won't be able to find a cause.

"We need to give them the resources to make sure they can identify a cause," Abruzzo said.

One leading environmental scientist said the health department's findings demand intense investigation.

The findings are unusual enough for scientists in his field to be studying the case nationwide, predicted Peter deFur, president of Environmental Stewardship Concepts in Richmond, Va.

Homeowners should insist on federal help, added deFur, who has served on several EPA advisory committees and on the National Academy of Sciences' Board on Environmental Studies and Toxicology.

He said the CDC should conduct a health assessment, which would involve looking at residents' medical records and taking blood and environmental samples.

Homeowners have expressed concern about exposure to farm chemicals, well water quality, a nearby Pratt & Whitney toxic-cleanup site, possibly contaminated fill dumped from other locations, cell phone towers, and naturally occurring radioactive substances in rock. The community may be experiencing a "cumulative risk situation" where stresses are added upon stresses until people's systems can no longer handle them, deFur said.

The fact that the health department found a greater disparity in girls than boys raises a question of whether a hormone-disrupting chemical could be involved, he said.

The state Department of Environmental Protection, which is not part of the cluster investigation, isn't planning to conduct any tests, spokeswoman Cristina Llorens said. The agency randomly sampled 50 wells last year and declared that ground water quality in The Acreage was "generally good," despite some elevated levels of radiation that could come from natural causes.

Monday's news came as a result of state health officials updating population data for The Acreage to hone their preliminary findings.

They had originally used a population estimate of 29,000 residents based on the 2000 U.S. Census. But updated population figures estimate that 32,000 to 39,000 live in the semi-rural community. Even with the bigger population, the number of reported cancer cases is abnormally high.

The scope of the investigation is from 1993 through 2008. The significant jump in the number of cases occurred after 2002, said Dr. Tammie Johnson, a state epidemiologist.

By mid-March, the state health department expects to finish and report on the second phase of its investigation, which includes interviews with 12 families and analyses of cancer rates based on updated population data. If it starts a third phase, which could involve environmental tests, that would take up to a year to finish.

Or the investigation could jump directly to a fourth phase, county health department spokesman Tim O'Connor said. That would likely be a large-scale federal or university-based project.

It's unclear how the cluster declaration will affect real estate in The Acreage. "I'm I hoping they resolve (the investigation) quickly," said Nancy Drysdale, who's been selling homes there since 1978.

The sooner the better, said Richard Cotromano, whose daughter was diagnosed with a tumor at 6 months old in 2004.

The important thing is for the health department to start testing the water and soil, especially at the homes of victims like his daughter, he said.

"I'm hoping they find a reason because I want to know," he said.

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