スリーマイル島原発事故と甲状腺がん発症には因果関係がある＝米国ペンシルベニア州医療センターが医学誌に発表
Three Mile Island nuke accident linked to thyroid cancer
USA TODAY NETWORKBrett Sholtis, York (Pa.) Daily RecordPublished 8:49 p.m. ET May 31, 2017 | Updated 6:15 p.m. ET June 1, 2017
In March, 1979 a near meltdown happened at the Three Mile Island Nuclear power plant. Wochit
(Photo: Matt Rourke, AP)
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A new Penn State Medical Center study has found a link between the 1979 Three Mile Island nuclear accident and thyroid cancer cases in south-central Pennsylvania.
The study marks the first time the partial meltdown of Unit 2's reactor can be connected to specific cancer cases, the researchers have said.
The findings may pose a dramatic challenge to the nuclear energy industry's position that the radiation released had no effect on human health.
The study was published Monday in the medical journal Laryngoscope, one day before Exelon Corp. (EXC) announced that Three Mile Island would close in 2019. It’s likely to come as another blow to a nuclear-power industry already struggling to stay profitable.
► Tuesday: Three Mile Island nuke plant, scene of partial meltdown, to close
► Feb. 15: Harold Denton, Three Mile Island hero, dies
► Feb. 15: Harold Denton, Three Mile Island hero, dies
Exelon officials declined to comment on the findings, pointing out that it doesn’t own the damaged reactor and wasn’t running the plant during the accident.
Dr. David Goldenberg, a surgeon and thyroid researcher, led the study after seeing anecdotal evidence for a connection.
“I’m always wary when people say ‘there’s nothing to see, here. ... This is the furthest we’ve come. There are 44 patients in this study. It’s by no means conclusive.”
Dr. David Goldenberg, Penn State University
“I’m always wary when people say ‘there’s nothing to see, here,' ” he said.
Although Pennsylvania has the nation’s highest rate of thyroid cancer, most of that cancer has nothing to do with Three Mile Island, Goldenberg said.
However, thyroid cancer caused by low-level radiation has a different “mutational signal” than most thyroid cancer, he said. He and his colleagues used molecular research that had been pioneered after the Chernobyl nuclear disaster to find that genetic signal.
The scientists screened out many thyroid cancer patients, limiting their study to 44 people who were born in counties around Three Mile Island, present during the March 28, 1979, accident and treated at Penn State Hershey Medical Center.
“We found a change in this signal from sporadic to radiation-induced in the affected timeline to those exposed to low-dose radiation,” Goldenberg said. Those people developed thyroid cancer on average five to 30 years after exposure and about 11 years earlier than the average thyroid cancer case.
Goldenberg stops short of saying that the accident “caused” the thyroid cancer, instead saying the accident and the cancer have a “possible correlation.”
“We found a change in this signal from sporadic to radiation-induced in the affected timeline to those exposed to low-dose radiation,” Goldenberg said. Those people developed thyroid cancer on average five to 30 years after exposure and about 11 years earlier than the average thyroid cancer case.
Goldenberg stops short of saying that the accident “caused” the thyroid cancer, instead saying the accident and the cancer have a “possible correlation.”
“I do stop short, and I’ll tell you why,” Goldenberg said. “This is the furthest we’ve come. There are 44 patients in this study. It’s by no means conclusive.”
► Jan. 6: N.Y.’s Indian Point nuke plant to close by 2021 under deal
► Jan. 4: Nation's only underground nuclear waste repository reopens
► Jan. 4: Nation's only underground nuclear waste repository reopens
The next step is to expand the study through tapping into resources from other regional hospitals, he said.
The study contradicts conclusions about Three Mile Island from many nuclear energy proponents, including the Nuclear Regulatory Commission. Three Mile Island gets its name because the island on which the nuclear plant sits is 3 miles down the Susquehanna River from Middletown, Pa.; it's also less than 15 miles downriver from Pennsylvania's state capital of Harrisburg.
“If you’re not asking the right questions, then you’re not going to get the right answers that society needs to have.”
Cindy Folkers, Beyond Nuclear
University of Pittsburgh Medical Center completed a study in 2000 that found the accident did not cause an increase in cancer mortality among people living within a five-mile radius of the plant, said Neil Sheehan, Nuclear Regulatory Commission spokesman.
The NRC is eager to review the new findings, Sheehan said. However, to date, evidence shows that the radiation released posed no danger to the community.
For those who have long disagreed with the industry, the new study adds credence to their beliefs. Cindy Folkers, a scientist at Beyond Nuclear, which opposes nuclear energy, said she’d be more surprised if the study had shown no connection.
Folkers takes issue with the way that the Nuclear Regulatory Commission and others have defined the level of exposure.
“They’ve called the shots on this conversation for a number of decades now," she said. "If you’re not asking the right questions, then you’re not going to get the right answers that society needs to have.”
She cited a 1997 study from a University of North Carolina Chapel Hill scientist, Steven Wing, that showed a connection between the accident and lung cancer and leukemia in a “plume” that traveled from the plant.
► Oct. 12: Dog rescued from 30-foot hole at old nuclear power plant
► May 2016: Troubled Indian Point nuke reactor to reopen
► May 2016: Troubled Indian Point nuke reactor to reopen
“It was the only study that actually showed a health impact, and it was because of how he looked at the data,” Folkers said. However, the nuclear energy industry dismissed it because they disagreed with its approach.
The new study, coming from a prominent university, is likely to reopen the inquiry into the accident, Folkers said.
It also could lead to another round of lawsuits, she said, referring to the 1996 class action where U.S. District Judge Sylvia H. Rambo ruled insufficient evidence to link radiation from the Three Mile Island accident to health problems in test cases of about 2,000 plaintiffs.
► August 2015: Japan restarts 1st nuke reactor since Fukushima meltdown
► February 2014: Nun sentenced to 35 months in Oak Ridge nuclear break-in
► February 2014: Nun sentenced to 35 months in Oak Ridge nuclear break-in
Christine Layman was 21 years old and living within five miles of Three Mile Island when the accident happened. Now, after suffering thyroid disease and other issues she attributes to radiation exposure, she is elated to read the new findings.
“This is just the beginning," Layman said. "This is going to open up everything.”
Layman is assistant to a filmmaker for a movie about Three Mile Island. For years, she and many others have looked to scientists to confirm what they believe — that Three Mile Island had more human health effects than what the government will say.
► October 2012: Sandy forces temporary shutdown of three nuclear plants
► October 2012: Wisconsin nuclear plant closing in 2013
► October 2012: Wisconsin nuclear plant closing in 2013
“All those years, watching everyone around me, watching everyone dying," Layman said. "Everybody in the Manchester (Pa.) area, it just seemed, had cancer.”
Goldenberg struggles with the knowledge that his findings also may lead some people to wrongly blame Three Mile Island for their medical issues. He knows that the study might be met with some opposition and emphasizes that it isn't his job to think about the consequences — only the data.
“I am not an advocate one way or another," He said. "I don’t care. I am a scientist. I go where the data takes me.”
Follow Brett Sholtis on Twitter: @BrettSholtis
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