West Virginia University researcher Michael Hendryx co-authored the new paper, which is based on door-to-door interviews with nearly 800 residents along the Coal River from Seth to Rock Creek.

"The odds for reporting cancer were twice as high in the mountaintop mining environment compared to the non-mining environment in ways not explained by the age, sex, smoking, occupational exposure, or family cancer history," Hendryx wrote.

The study, published in the Journal of Community Health, does not say mountaintop removal caused the increased cancer rates. But it says more research is needed to examine mining pollution and potential impacts on people who live near mountaintop removal mines.

"The results of this study and others previously cited on coal mining populations demonstrate that health disparities are concentrated in mountaintop mining areas of the region," the study said. "Efforts to reduce cancer and other health disparities in Appalachia must focus on mountaintop mining portions of the region."

Hendryx and a collection of colleagues have published a series of papers examining possible links between mountaintop removal and various illnesses, including a study last month that found higher rates of birth defects in communities near mining operations.

Collectively, the papers have given weight to citizen complaints about coal's impact on public health. Anti-mountaintop removal activists point to the research to show that the issue isn't just about mining effects on salamanders, mayflies or isolated mountain streams.

Obama administration officials have said they are concerned about the findings of the public health studies, and cited the findings in supporting a U.S. Environmental Protection Agency crackdown on mountaintop removal permit practices.

Mining industry groups have disputed the findings of the studies, and coalfield political leaders have mostly tried to ignore them. On Wednesday, Sens. Jay Rockefeller and Joe Manchin, both D-W.Va., refused requests for interviews about the growing body of research about mining and public health impacts.

Among the authors listed for the new paper was Bo Webb, a Coal River resident and activist who has long complained that he sees mining causing illnesses among his neighbors.

Webb and other residents contacted Hendryx and together they designed a door-to-door survey to try to investigate concerns of increased cancer rates in the area.

Students from area colleges volunteered to perform the interviews during their spring breaks. Interviews were also conducted in Pocahontas County, to provide a control group in an area with no mountaintop removal for comparison to the Boone and Raleigh results.

The study tried to account for some other potential influences on cancer, such as family history, gender, age, smoking and occupational exposures. But it did not account for obesity, and researchers said they were limited by trying to reduce the time necessary to do the interviews and complete the survey.

"There were concerns express by community partners that if the time spent per survey was prolonged, such that fewer surveys could be completed per day and more time had to be spent in Coal River to collect and adequate sample size, word about the survey taking place would reach the coal industry, and community residents would be instructed or pressured by industry representative not take part," the study said.

The study also did not attempt to count cancer deaths, meaning that some fatal cancers previously found at high rates in the area, such as lung cancer, were not represented in the results.

Residents interviewed in the Boone-Raleigh area reported an overall cancer rate of 14 percent, compared to a rate of 9 percent in Pocahontas County. After the results were adjusted for age, gender, smoking, occupational exposure, or family cancer history, the odds of having cancer were twice as high in the Coal River Valley area, the study said.

The National Cancer Institute reports a nationwide cancer rate of about 4 percent, while a West Virginia state report listed a statewide rate of 10 percent.

Hendryx wrote that if the rates found in the Coal River study were translated across the Appalachian region, it would result in an additional 60,000 people with cancer in communities where mountaintop removal is performed.

"Although these projections are uncertain, they illustrate the large numbers of people who are potentially impacted by mountaintop mining environments," the study said.

Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.