Tungsten levels high in some rural Nevada towns

Tuesday, June 17, 2003 | 9:33 a.m.

CARSON CITY -- The tungsten level found in urine tests of residents of Pahrump, Lovelock and Yerington are above the national level, the state Health Division announced Monday.

The findings appear to eliminate tungsten as a suspected cause of a cluster of childhood leukemia cases in and around rural Fallon, 80 miles southeast of Reno, state Epidmediologist Randall Todd said.

"The fact that an unusual number of leukemia cases was not observed suggests that exposure to tungsten elsewhere in Nevada can occur without the development of an increase in leukemia cases," Todd said.

Still, the federal Centers for Disease Control and Prevention in Atlanta is seeking more research on the effect of tungsten and its compounds to human health.

The study in the rural Nevada towns was done after 16 cases of childhood leukemia were found among Churchill County residents and former residents in recent years. Three of those children have died.

An elevated level of tungsten was found in Churchill County residents, among those with and without the disease in their families. The study aimed to determine how widespread that was in Nevada.

The levels in the three communities studies were higher than those found among 95 percent of the national comparison population. Authorities said this is likely the result of Nevada's geology, which is rich in tungsten.

Authorities said there are no scientific studies to link tungsten exposure to leukemia. Todd said the state has not identified any unusual number of leukemia cases in Pahrump, Lovelock and Yerington.

The federal CDC has recommended the National Toxicology Program of the National Institutes of health review existing literature then conduct toxicologic research of tungsten and tungsten compounds to determine their potential link to cancer in humans.

The centers said, "In Lovelock and Pahrump, we found no significant relations between water tungsten levels and urine tungsten levels. We did find a correlation between urine and water tungsten levels in Yerington.

"Yerington's overall urinary tungsten levels were similar to those in Churchill County," the center said. "Lovelock and Pahrump had levels significantly lower than Churchill County and Yerington.

"Children had consistently higher urinary tungsten levels than adults across all study populations," the center said.