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Is there a link between leukemia and nuclear power?IPPNW-Germany's
study this week finds that there is a correlation between developing cancer before
one's fifth birthday and the distance between home and a nuclear power plant.
Published on Friday, December 14, 2007 by Reformer.com By Bob Audette,
Reformer Staff BRATTLEBORO -- While no one can deny radiation
exposure is not healthy for living organisms, studies conducted since nuclear
power became one of the major sources of electricity in the United States have
concluded there is no link between it and cancer. However, a study of childhood
leukemia released this week by the German branch of the International Physicians
for the Prevention of Nuclear War reported "there is a correlation between
the distance of the home from the nearest nuclear power plant and the risk of
developing cancer before (the) fifth birthday."
The study's authors
cautioned however, that "the present status of radiobiological and epidemiological
knowledge does not allow the conclusion that ionizing radiation emitted by German
nuclear power plants during normal operation is the cause."
"There's
a fair probability that the results they got were strictly by chance association,"
said William Irwin, the radiological health chief with Vermont's Department of
Health, who admitted he hasn't yet read the whole study.
However, he said,
the authors of the report are highly respected and it's crucial that studies such
as that from the IPPNW continue.
"It's extremely important for those in public health and academia to
continually look at the information about health outcomes of those who live near
the facilities and those who work at these facilities," said Irwin.
In
1991, a study conducted by the National Cancer Institute concluded "the risks
for childhood leukemia, adult leukemia and all cancers were about the same in
the counties with nuclear installations as in the control counties."
In
fact, stated the report, those concerned about the effects of ionizing radiation
on their bodies and their children's bodies would be better served by limiting
the effects of cigarette smoke, radon and an unhealthy diet.
Closer to
home, the NCI report stated leukemia deaths in children ages 10 to 19 in Windham
County had actually decreased in the 19 years between 1972 - the year Vermont
Yankee in Vernon began producing electricity - and 1991, when the study was conducted.
The Vernon Elementary School -- which is a mere 1,000 yards from the General
Electric boiling water reactor inside Yankee's containment vessel -- was built
in 1954, 18 years before Vermont Yankee came on line. If radiation emitted by
the plant was causing cancer in children, conclude many supporters of nuclear
power, in the 35 years since the plant opened why haven't cancer rates increased
in children who have attended the school?
When Vermont Yankee started producing
power, said Irwin, Vermont was the regulatory body because the Nuclear Regulatory
Commission had not yet been established. At the time, regulators discovered radiation
emission levels were higher than acceptable.
"They installed a special
shield wall to reduce those radiation levels," said Irwin. That level of
cooperation is an indication of the desire of both state regulators and the operators
of Yankee to protect the public health, he said.
The 2006 surveillance
report of Vermont Yankee released in June 2007 by Vermont's Department of Health
would seem to support the conclusion that measures taken to limit the public's
exposure to radiation are working.
The report stated that "cancer
incidence and cancer mortality rates in the communities around Vermont Yankee
were found not to differ significantly from those in the rest of Windham County,
Vermont or the United States."
Comparisons to long-term historical
trends "show no significant increased radiological exposures due to Vermont
Yankee nuclear power station operations," stated the report.
"That's
the whole basis for regulatory limits," said Irwin. "You attempt to
establish them where you will not see statistical significant differences (between
those exposed to radiation and those not exposed)."
Even with an increase
of power production by 20 percent in 2006, radiological readings around the plant
"appear to support the premise that the (newly installed) turbine shield
negates the increased direct gamma radiation levels of the extended power uprate,"
according to the surveillance report.
"For all cancer types combined,
the rate of cancer incidence in the six towns near Vermont Yankee is lower compared
to the rest of Vermont and the United States as a whole," stated the report.
"Characterizations that one population is at more risk or at less risk as
compared to another are not valid."
As a whole, stated the report,
cancer rates for white males and females in the United States average 489 cases
per 100,000 people. "In the six towns near Vermont Yankee, the all cancer
incidence rate is 434 cases per 100,000 persons." People in those six towns
"were diagnosed with fewer cancers between 1994 and 2003 than Vermont and
the U.S."
While it appears that deaths from leukemia in the six towns
"may be higher in Windham County the difference is not statistically significant."
While the state average for leukemia is 7.6 deaths per 100,000 people, that number
is 8.33 per 100,000 in Windham County.
Cancer and nuclear power was on
Sally Shaw's mind when she submitted a petition for rulemaking to the NRC in 2006.
Shaw, a Gill, Mass., resident, asked the Nuclear Regulatory Commission to reconcile
a 2005 National Academy of Sciences report on the dangers of ionizing radiation
with standards in the NRC's generic environmental impact study for nuclear power
plants.
The 700-page NAS report stated "there is no safe level or
threshold of ionizing radiation exposure. Even exposure to background radiation
causes some cancers. Additional exposures cause additional risks."
The
report stated that one in 100 members of the public would get cancer "if
exposed to 100 millirems per year for a 70-year lifetime. This is essentially
the U.S. Nuclear Regulatory Commission's allowable radiation dose for members
of the public." The 100 millirems threshold is in addition to any background
radiation a member of the public might get from environmental sources.
The
NAS study also concluded that nuclear workers have an increased risk of cancer
if exposed to the NRC upper limits of radiation for industrial employees.
However,
on Dec. 12, the NRC rejected Shaw's petition.
"The overall risk estimates
of the report remain(s) statistically insignificant," wrote the NRC in its
decision. "The NRC staff concluded that the findings presented in the report
agree with the NRC's current understanding of the health risks of exposure to
ionizing radiation. None of the findings represent new and significant information
"
The NAS and IPPNW reports are just two of many that have been written
on the subject of the effects of ionizing radiation from nuclear power plants.
A study conducted after the Three Mile Island Accident in 1979 concluded
there were no increases in cancer mortality in populations living within a five-mile
radius of the power plant in Harrisburg, Pa.
The study, released in 2000,
which was conducted by the University of Pittsburgh's Graduate School of Public
Health, reviewed cancer rates between 1979 and 1992.
"Scientists have
calculated that the average person present in the area during the 10 days after
the incident was exposed to considerably less radiation than the annual dose an
individual receives from the everyday environment in the United States,"
wrote the researchers.
However, wrote the authors, while they found "no
consistent evidence suggesting that the low-dose radiation released during the
TMI accident had a measurable impact on the mortality of those living in the area
for 13 years after the event, they acknowledge that further study is warranted."
A study released a year later, conducted by the Connecticut Academy of
Science and Engineering, concluded there were "no meaningful associations
among the cancers studied (pediatric leukemia, adult chronic leukemia, multiple
myeloma, and thyroid cancer) and proximity to Connecticut Yankee nuclear power
plant (in Haddam Neck)."
Also in 2001, the American Cancer Society
concluded that cancer clusters "do not occur more often near nuclear plants
than they do by chance elsewhere in the population."
As far as the
health of power plant workers is concerned, a 2004 report issued by Columbia University's
Mailman School of Public Health, which looked at more than 53,000 nuclear power
workers, concluded the workers were "less likely to die from cancer or non-cancer
diseases due, in large measure, to the so-called 'healthy worker effect.'"
Employees of the nuclear industry "have to be healthy and are usually
required to have annual medical check-ups," the so-called "healthy worker
effect."
The study, which tracked employees from 15 nuclear utilities
from 1979 to 1997 concluded the workers had mortality rates that were 60 percent
lower than similar populations around the country.
The results related
to workers at nuclear power plants "is strong support for the regulatory
limits that exist," said Irwin.
At the same time, concluded the report,
researchers found a "statistically significant association between radiation
dose and death from arteriosclerotic heart disease, including coronary heart disease,"
warranting further study.
A report from the NRC stated studies that contradict
the plethora of studies conducted over the years often are flawed because they
didn't examine the effects of other risk factors, used small sample sizes, did
not conduct environmental sampling and analysis, chose to ignore data that did
not "fit" their conclusions and were not subjected to peer review. Close
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