A new study
out of Russia says that children in some areas near Kazakhstan's Baikonur Cosmodrome are twice as likely to require medical attention
as other children in the region.
According to an unpublished report, the cause of illness is
believed to be highly toxic fuel from spent rocket stages that spills onto the
sparsely population region. Baikonur is
where Russia's space agency conducts a majority of its space launches. The report
was
revealed today in the journal Nature.
The announcement follows the release this week of a separate
study of
the risk here in the United States of perchlorate, a rocket-fuel
component known to be health-threatening. The chemical has been found in the drinking water of
at least 11 million U.S. residents. Traces of perchlorate have also been found in lettuce
and milk.
The Russian study was done
by Vector, the State Research Center of Virology and Biotechnology. The researchers
examined health records from 1998 to 2000 of 1,000 children in two polluted
areas, along with the records of 330 children in a nearby unpolluted area.
The study is controversial
even before it has been officially released.
Baikonur is a significant
revenue source for the Russian government, the journal notes, estimating that
profit from a single commercial launch may be as high as $25 million. The spaceport
is critical to NASA, too. It is the only place from which supplies and crews
headed for the International Space Station can be lofted into orbit while the
U.S. shuttle fleet is grounded. NASA and the European Space Agency (ESA) both
contract with their Russian counterpart to use Baikonur.
The Russian government has
rejected the results of the study while medical experts elsewhere say they have
not had a chance to judge its validity.
U.S. contamination
While NASA's uses its Florida-based
Cape Canaveral facility to launch rockets out over the sea rather than
over populated areas, the United States
is not free of Space Age contamination.
A study in 2003 found that
lettuce grown in parts of the western United States were tainted with perchlorate,
the main component of rocket fuel and missile propellant. It is in the drinking
water of between 11 million and 20 million people in several states, various
studies conclude.
Among contaminated sources
is the Colorado River, which provides water to Los Angeles, Phoenix and Las
Vegas and is used to irrigate 70 percent of the nation's lettuce crops, according
to the Environmental Working Group, which performed the 2003 study in cooperation
with scientists at Texas Tech University.
Most of the perchlorate
in U.S. water comes from military bases or plants operated by federal defense
contractors, the study's scientists said. Perchlorate is also a component of
fireworks.
In excess quantities, perchlorate
is thought to disrupt the production of hormones and, in fetuses, potentially
cause mental retardation, loss of hearing and speech, and motor skill deficits.
In adults, high doses can disrupt the function of the thyroid gland.
Another
study by the Environmental Working Group found perchlorate levels in milk ranging
from 1.7 to 6.4 parts per billion. The group has urged state and federal agencies
to consider stricter procedures to measure and control the contamination.
New research
A follow-up study in 2004
by the Food and Drug Administration (FDA) found traces of perchlorate in bottled
water at retail stores, in milk across the country, and in lettuce tested in
several states. FDA officials said there is no cause for alarm, and that further
study was needed to determine just how toxic the chemical is.
"The scope of the data
is too limited" for any conclusions to be drawn, according to an FDA statement,
which advised: "Until more is known about the health effects of perchlorate
and its occurrence in foods, FDA continues to recommend that consumers eat a
balanced diet."
According
to the Environmental Protection Agency (EPA), perchlorate
is present in the drinking water of 11 million Americans at concentrations of
4 parts per billion or higher. In an effort to determine acceptable limits of
perchlorate consumption, the EPA set a "daily reference dose" of 0.00003
milligrams per kilogram of body weight, which the agency said would correspond
to a drinking-water concentration of 1 part per billion based on assumptions
about body weight and daily water consumption.
An new study of perchlorate
risk, just released by the National Academies' National Research Council (NRC)
on Monday, suggests doses up to 20 times higher may be acceptable.
"Daily ingestion of
up to 0.0007 milligrams per kilogram of body weight can occur without adversely
affecting the health of even the most sensitive populations," the NRC report
concludes.
The NRC researchers, scientists
from various institutions and fields of expertise, drew on past studies in which
patients have been administered perchlorate, ironically to treat thyroid conditions.
"A few patients had
serious adverse reactions," the NRC states, but more recently "patients
with hyperthyroidism have been treated effectively and safely with moderate
doses of perchlorate for up to two years."
A perchlorate dose of more
than 0.4 milligrams
per kilogram
per day would be required "to adversely affect thyroid hormone production and
cause hypothyroidism," the study concludes. "However, the dose required to cause
hypothyroidism in pregnant women, infants, children, and people with low iodide
intake or pre-existing thyroid dysfunction might be lower."
Lauren Sucher, a spokesperson
for the Environmental Working Group, said in a telephone interview today that
the EPA will have to consider other factors in setting a drinking water standard,
however. Babies, for example, are at higher risk due in part to their lower
body weight.
"Once the EPA takes
into account childrens' and babies' exposure to this rocket fuel component and
figures in food exposure, they should reach a much lower drinking water standard,"
Sucher told SPACE.com.
Confusion near Baikonur
Near Baikonur, a variety
of illnesses were noted.
The level of some blood
and endocrine, or gland disorders in polluted areas is more than twice the regional
average. But experts outside Russia who have seen the study can't verify how
the data was collected. "They
say that although such results should be regarded with caution, given the sometimes
disorganized state of the country's medical records, the problem deserves international
attention," the journal states.
The study was led by epidemiologist
Sergey Zykov, who said it confirms pollution fears raised by environmental groups.
Zykov said Russian space agency officials had a "negative attitude" to studies
from outside the agency. Another scientist who has campaigned against launches
alleges to have been harassed by security officials, the journal article said.
Nature confronted
Russian officials, who admit there's pollution but "rejected the conclusions
of Zykov's study."
There are other complexities.
Valerie Beral, an epidemiologist
at Cancer Research UK in Oxford, said some studies of the 1986 Chernobyl nuclear
accident produced conclusions that could not be replicated by other scientists.
In some cases, Russian researchers have been accused of releasing alarming findings
to attract funding from the West.
In an editorial, the journal
said "ESA and NASA use Baikonur, but neither they nor the Russian administrators
of the base seem overly concerned about the population." Further study
is needed, the editorial urged, and ESA and NASA should contribute to financing
it.
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