Professor speaks about leukemia cluster findings

RENO - Dozens of students and others interested in the Fallon leukemia cluster attended a seminar from Dr. Mark Witten from the University of Arizona Monday at the University of Nevada, Reno campus.

Witten, Dr. Paul Sheppard, Dr. Gary Ridenour, Robert Speakman and other researchers along with FIST (Families in Search of Truth) continue efforts through grant funding to research the cause of the leukemia cluster in Fallon in which 17 children were diagnosed and three died between 1997 and 2004.

During the lecture, material was used from recently released studies on surface dust and lichen and tree rings, as well as the Centers for Disease Control's gene study released in late 2006.

Witten said the information will help researchers, scientists and doctors to continue receiving funding for future research.

He said studies of gestating mice indicate strong evidence that leukemia originates prenatally. Studies were performed with male and female mice before, during and after gestation. He said part of the hypothesis is in-utero exposure to tungsten and arsenic promotes long-term silencing of the tumor suppressor genes that are specifically related to B-cell leukemia.

When questioned about the possible source, Witten replied "My goal is to find out why these kids got leukemia."

He said each place where childhood leukemia cases were discovered and studied, such as Fallon, Sierra Vista, Ariz., and the Calvine-Florin area off Highway 99 in Sacramento, Calif., tungsten is present along with cases of other rare cancers.

Fallon had higher tungsten levels than in the other locations; however, it was still present at each location.

"What are the odds of all this happening - naturally?" he said.

The percentage of Fallon leukemia cases was much higher than the national average, according to the tree ring study report. According to the CDC, the average is 4.3 cases per 100,000 children from age 0 through 19 per year. According to the U.S. Census Bureau, in 2000, Fallon had a population of 7,536. Of that, 2,400 qualified as children.

"Fallon is 18 percent above the national average," said Witten. "I believe there are really about 20 cases. There is a brain cancer cluster there as well, it just hasn't been investigated yet."

Although the heavy metal, tungsten, was found at each location, it was in lower concentrations than found in Fallon. The cobalt that was evident in Fallon was not evident at the other two locations. Arsenic that was discovered in higher levels than any other location in the country was evident in smaller amounts in Arizona and California, said Witten.

In California there were six cases of leukemia and five cases of breast cancer in a two- block radius, said Witten. The location where the homes were built was the location of a plant that manufactured huge radiators many years ago.

"We think that's where the tungsten is coming from," said Witten.

Sheppard said the tree ring study indicates elevated tungsten levels at about the mid-1990s.

"About the same time or slightly before the onset of Fallon's cluster of childhood leukemia," he said in an e-mail Tuesday. "This covariable timing is intriguing, but by itself doesn't necessarily establish a cause and effect linkage between tungsten and leukemia."

He said biomedical testing is needed to find such a linkage. Future studies should include environmental research to find replicates or opposites of the Fallon cluster.

Sheppard said tracer studies are useful in testing for sources of origin. This could be useful information for the Fallon cluster.

Witten said future studies include: Determining leukemogenic-effect of cobalt and tungsten/cobalt exposures administered pre-natally and continued post-natally; studies to determine the effect of prenatal exposures to tungsten and/or arsenic on Piccolo gene-expression; and determining the effects of tungsten and/or arsenic on spermatogenesis, the process that creates functional sperm.