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The Associated Press
Jun 18, 2003 : 4:21 am ET
FALLON, Nev. -- Tungsten probably is not the
main cause of a Fallon leukemia cluster that has sickened 16
children and killed three since 1997, federal scientists said.
The Centers for Disease Control and
Prevention found that the metal shows up in elevated levels all over
Nevada, including areas where leukemia cases are within normal
ranges.
Tungsten had been suspected of causing the
Fallon outbreak because it turned up in unusually high levels in the
area's population.
Tests this year also showed high levels of
tungsten in residents of Yerington, Pahrump and Lovelock, but the
communities have shown normal levels of leukemia cases.
"This decreases the probability that tungsten
is the cause" of the Fallon outbreak, state epidemiologist Randall
Todd said.
Despite the findings, government scientists
did not rule out tungsten as a contributing factor in the Fallon
outbreak.
The metal might act in combination with
something else present in the small Navy and farm town 60 miles east
of Reno, Todd said.
Mark Witten, an Arizona toxicologist who has
been studying tungsten in tree rings in communities with cancer
clusters, said he still thinks the metal is a prime suspect in the
Fallon cluster.
His team has found increasing tungsten levels
in tree rings in four communities: Fallon; Sierra Vista, Ariz.;
Sacramento County, Calif.; and Hoisington, Kan.
"Four out of four areas where there are
leukemia clusters are showing increasing tungsten levels over time,
and yet we're not seeing the same kind of consistent increases in
trees in Lovelock or Fernley," Witten said.
Tungsten is naturally occurring in the Fallon
area, and tungsten ore was smelted in an open-air kiln 10 miles
north of Fallon for three decades.
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