Three Mile Island:

A troubling new report

ION Science 03/10/97

Exposure to radiation shortly after the 1979 nuclear accident at Three Mile Island in Harrisburg, Pennsylvania, may have indeed increased cancer among populations downwind of the plant, scientists at the University of North Carolina report, contrary to a previous study.

Dr. Steven Wing, associate professor of epidemiology, led a study of cancer cases within 10 miles of the nuclear power plant from 1975 to 1985. He and colleagues conclude that following the accident, lung cancer and leukemia rates were two to 10 times higher downwind of the Three Mile Island reactor than upwind. A paper Wing and colleagues wrote appears in the journal Environmental Health Perspectives.

The new study involved re-analyzing data from a 1990 Columbia University study that concluded the nation's worst civilian nuclear accident was not responsible for slightly increased cancer rates near the plant because radiation exposures were too low.

"I would be the first to say that our study doesn't prove by itself that there were high-level radiation exposures, but it is part of a body of evidence that is consistent with high exposures," Wing said. "The cancer findings, along with studies of animals, plants and chromosomal damage in Three Mile Island area residents, all point to much higher radiation levels than were previously reported. If you say that there was no high radiation, then you are left with higher cancer rates downwind of the plume that are otherwise unexplainable."

Limitations of the new study, like the earlier work, include the continuing difficulty of determining precise wind direction for several days following the accident.

A particularly troubling aspect of the continuing investigation of long-term effects of the disaster revolve around U.S. District Court Judge Sylvia Rambo, who dismissed more than 2,000 damage claims filed against the power plant by nearby residents last year citing a "paucity of proof" to support their cases: What were the judge's exclusion criteria and what qualified her to decide what these criteria should be?

This case and several other nationally prominent trials in the recent past have begun an important public debate as scientific evidence introduced in courtrooms becomes increasingly complex, and the quality of science education in the U.S. continues to fall. Can non-scientist judges and jury members reliably interpret complex matters of scientific evidence, assess the qualifications of "expert" scientific witnesses who may be paid handsomely for their testimony, and sort science opinion from science fact? Can lawyers?

--From ION Science news service