The hunt is on for a mystery killer

 

Leukemia cluster has Nevada town thirsty for answers

FALLON, Nev. — The Fallon high school girls’ basketball team, the Greenwave, had a banner year. The team racked up a 19-7 record — beating teams from larger schools in nearby Reno and Sparks — and rolled into the state tournament this winter. What’s their secret? The players’ warm-up jerseys are emblazoned with a cryptic slogan: "Maybe you should try our water."

"It was kind of a joke," says coach Chelle Dalager, who coined the slogan, "because the teams that came to play us would bring in bottled water instead of drinking the water we set out for them."

Fallon, a sleepy town that sits on U.S. Highway 50 — "the loneliest road in America" — is grappling with tough questions about what really is in its water. An agricultural community known for its sweet cantaloupes and the Fallon Naval Air Station, where fighter pilots hone their skills in the Top Gun air combat training program, the town has drawn national media attention as the home of the fastest-growing cancer cluster in United States history.

Nationwide, only three people out of 100,000 contract acute lymphocytic leukemia, the most common form of childhood leukemia. But in Fallon, with a population of 7,500, 16 cases of the disease have been documented in the last five years. All were children under the age of 20 when diagnosed, and three have since died.

Among them was Stephanie Sands, who died in September 2001, at the age of 21. Her family had moved from Fallon to Pennsylvania in 1995, but, following her death, Stephanie’s father, Floyd, returned to Nevada to look for answers. The U.S. Centers for Disease Control (CDC) and the Nevada State Health Division had been studying the situation, but Sands was frustrated by the lack of progress. He decided to go door-to-door, asking his former neighbors about cancer and other sicknesses in their families. In just a few months, he came up with a grim tally.

"The bottom line is the community is suffering," says Sands, "and no one’s doing a damn thing about it."

Plenty of suspects

State and federal health officials say they face a daunting challenge in uncovering the cancer cluster’s cause. "This is like a very complicated jigsaw puzzle," says Nevada state epidemiologist Randall Todd, "where someone threw away the box."

Three cases of childhood leukemia were reported in Fallon and surrounding Churchill County between 1997 and 1999, but the situation reached crisis proportions in 2000, when physicians diagnosed nine children with the disease. The state health division responded in February 2001 by asking the CDC to join the investigation.

Dr. Martin Belson, a CDC toxicologist assigned to the case, says there was no shortage of initial suspects. Fallon has high levels of arsenic, a known carcinogen, in its drinking water. The neighboring Fallon Naval Air Station imports JP-8 jet fuel, which contains volatile organic compounds linked to leukemia, through a pipeline that runs underneath the town; some residents say the pipeline has leaked in the past. Agricultural pesticides and radioactive fallout from a 1963 nuclear test 30 miles east of town rounded out the list of possible causes.

In August 2001, the CDC began testing 205 Fallon residents, including leukemia patients and their families. Scientists analyzed urine, blood and cheek swabs, as well as air, tap water, dust and soil for signs of metals, volatile organic compounds, pesticides and other chemicals.

The final results of the tests, released at a public meeting this February, showed high levels of arsenic. This was expected, but officials pointed out that arsenic, while a carcinogen, has never been linked to leukemia. The tests revealed no alarming levels of jet fuel chemicals or signs of ongoing exposure to persistent pesticides.

But the CDC did find something no one had expected: Levels of tungsten, measured in urine samples, were up to 11 times greater than the national average. Says the CDC’s Belson, "There has not been a community with (tungsten) levels like this."

Tungsten is an extremely hard mineral used in alloys for rock drill bits and artillery shell tips. Churchill County, where Fallon is located, has 17 small inactive mines. The Kennametal tungsten refinery, which processed tungsten without air pollution controls from 1974 through 1994, is 10 miles outside of Fallon.

Tests by the U.S. Geological Survey discovered that both Fallon’s municipal water supply — a groundwater aquifer — and some private wells were highly contaminated with tungsten, suggesting that people had picked up the metal from the water.

But tungsten, a hard and stable mineral, has never been a suspected environmental health threat. The high levels of tungsten were "somewhat of a surprise," says Belson, "but we really didn’t know — and still don’t know — what it means."

A possible culprit

As the CDC conducted its tests, Dr. Mark Witten, a University of Arizona toxicology and pediatrics professor, began independently looking at the leukemia cluster in Fallon and another in Sierra Vista, Ariz., which also borders a military base that uses JP-8 jet fuel. Witten, along with a University of Arizona tree ring specialist named Paul Sheppard, decided to screen for a number of metals by analyzing core samples from trees, which accumulate chemicals — and metals — from the environment. In Fallon, they found a 118 percent increase in tungsten over the past 20 years — and similar results in tree cores from Sierra Vista.

Witten disputes the conventional wisdom that tungsten is harmless to humans: "It’s not inert, it’s not benign — it just hasn’t been studied." He has conducted lab tests of tungsten on cell cultures, and while he’s waiting to release his results until they are peer-reviewed, he says he’s "seen a response" in leukemia cell growth.

The CDC, meanwhile, has recommended that the National Institutes of Health start research on tungsten and its potential link to cancer. The CDC is now testing for tungsten in three other Nevada towns — without Fallon’s health problems — to see if they have similar elevated levels. The agency may then try to determine where the tungsten in the water is coming from.

In the meantime, Fallon is building a water treatment plant that will remove arsenic but not tungsten. Some families have chosen to install their own reverse-osmosis units that remove both metals.

"Finding the cause is not going to withdraw the sickness from our kids," says Sands. The health problems in Fallon extend beyond the 16 children who have contracted leukemia. Sands’ door-to-door survey turned up numerous cases of other childhood diseases, as well as cancer and adult leukemia. "A lot of these folks have called (the state health division) and they’ve been dismissed and ignored," says Sands. "This is improperly named ‘the Fallon childhood leukemia cluster.’ It’s a far bigger picture. There is something radically, radically wrong in Fallon, Nevada."

The writer, a former High Country News intern, is a freelance writer in Paonia, Colorado.

    You can contact ...

    Susan McClure, U.S. Centers for Disease Control, 770/488-4628;

    Dr. Mark Witten, University of Arizona College of Medicine, 520/626-2610;

    Floyd Sands, stephanieswalk@yahoo.com;

    Or, see the Nevada State Health Division Web site, http://health2k.state.nv.us/.