Even though pollution from the Fernald plant may have been fatal to dozens of people, some experts say the public health threat may not be big enough to justify spending millions on a full-blown epidemiology study.
A study released Wednesday
by the federal Centers for Disease Control and Prevention estimated that 85 people have died or will die from lung cancer caused by radon gas emitted by wastes stored at the former uranium foundry. That's about a 3 percent increase over the 2,600 lung cancer deaths that would be expected in the area.
The death estimate spans a period from 1951 - when construction started at Fernald - to 2088 - when infants born the year production stopped would be 100 years old.
Critics of the Department of Energy, which for years denied that Fernald posed a health hazard to neighbors, saw vindication in the death estimates. Yet the relatively low number of deaths also may provide some public reassurance.
"We're talking about less than one extra case of cancer a year. There are lots of bigger public health threats out there," said Ralph Buncher, an epidemiologist with the University of Cincinnati's Department of Environmental Health.
"Tornadoes probably will kill more people in the next 10 years. And I-75 will do its share," Dr. Buncher said.
The big question now is what to do with this information. Should more money be spent for another lung cancer study, one that counts real people rather than using mathematical models? Should the CDC sponsor a public education campaign about Fernald's health risks?
Should new studies focus on other health concerns, such as estimating the risks posed by toxic non-radioactive chemicals used at Fernald? Or all of the above?
The Fernald Health Effects Subcommittee, a 15-member group of health experts, residents and others, has been meeting since 1996 to make recommendations to the CDC about what kinds of health information the community wants about Fernald.
The committee must decide whether to recommend conducting a full-blown epidemiology study.
Unlike the model-based estimate released Wednesday, an epidemiology study would involve a rigorous counting of actual cancer deaths among Fernald neighbors, which could be compared to national or local norms.
After counting real cancer deaths among Fernald neighbors, scientists would plot where the cancer victims lived and for how long. Then they would use data about Fernald's pollution releases to estimate how much of a radiation dose each person received.
Then researchers could determine whether there really was a strong correlation between cancer deaths and long-term, low-level radiation exposure. Such a study could have worldwide medical value because most information about radiation risks is based on studies of small groups of people who faced high exposures, such as atomic bomb and nuclear accident survivors and uranium miners. But such a study would cost several million dollars and take years. "Is one death a year worth spending the kind of dollars we're talking about?" Dr. Buncher asked.
In addition to policy questions, a Fernald epidemiology study faces serious technical hurdles, said Dr. Owen Devine, chief of the CDC's risk assessment division. For example, it may not be possible to trace lung cancer victims, their medical records, their place of residence, their smoking habits, and other factors all the way back to the 1950s.
The margins of error in an epidemiology study could exceed the 3 percent increased lifetime cancer risk that experts now say the average Fernald neighbor faced. That means the study may not be able to find what it's looking for, Dr. Devine said, even though the health risk is real.
Several committee members have suggested launching health education projects to help long-time Fernald neighbors reduce their lung cancer risks.
Smokers who quit can dramatically reduce their health risks. So can people who repair homes with high levels of indoor radon gas. Regular medical checkups also may help improve survival times for potential lung cancer victims, by catching the disease early. These steps, plus advances in medical science, could change the results of the Fernald lung cancer study.
"You may now have some cells in your body that given the opportunity may turn into a cancer. But if you eat a healthy diet and lead a healthy life, that exposure is less likely to cause you a problem," Dr. Buncher said. "(Meanwhile) In the next 25 years, there may be a cure for lung cancer. That would certainly change the death estimates."