That study found 684 excess lung cancer deaths in Appalachia during those years. Most of those, the study said, were the result of other factors like smoking. After adjusting for those factors, the study still found 144 excess deaths over the five-year period, or about 29 per year.

Later this spring, another paper by Hendryx in the new journal Environmental Justice will examine total excess deaths from all causes in coal-mining counties in Appalachia.

After adjusting for other possible factors, coal-mining counties experienced 1,607 excess deaths during a six-year period between 1999 and 2004, Hendryx said. That amounts to about 268 excess deaths per year, he said.

"The incidence of mortality has been consistently higher in coal-mining areas for as long as the Centers for Disease Control rates are available, back to 1979," Hendryx said.

So far, Hendryx's work does not make a direct link between coal industry pollution and the increased illnesses. His studies have not yet examined specific emissions figures, or tried to conduct detailed reviews of how residents might be exposed to such pollution.

More research is needed on such matters, Hendryx said, but possibilities include exposure to coal byproducts such as slurry leaching into drinking water or air pollution effects from mining and coal processing.

But public health officials say that simply comparing the illness data for coal counties to non-coal counties provides a start for more in-depth examination of residents' concerns.

"This kind of study has value, because of its exploratory nature," said Celeste Monforton, a former federal mine regulator who teaches and studies public health at George Washington University. "Interested researchers can take the data and add data of their own and try to figure out what's going on."

In West Virginia, officials from the state Bureau for Public Health referred questions to agency epidemiologist Loretta Haddy, who did not return phone calls or e-mail messages on Tuesday.

Stephanie Timmermeyer, secretary of the state Department of Environmental Protection, wanted more time to review the study before commenting on it, said DEP spokeswoman Kathy Cosco.

State and national coal industry officials said they would review the studies.

"We need to find out the basis for it, and what's behind it all," said Bill Raney, West Virginia Coal Association president.

Hendryx said while coal is a major economic player in the state, the impacts of mining on communities should not be forgotten.

"I think we have to be honest about the effects of coal on communities and not just pretend these things don't exist," he said.

To contact staff writer Ken Ward Jr., use e-mail or call 348-1702.

Now, a West Virginia University researcher who has spent more than seven years looking into the issue says those residents may be onto something.

West Virginians who live in the state's coalfield counties are more likely than other residents to suffer from chronic heart, lung and kidney disease, WVU researcher Michael Hendryx reports in one of a series of new scientific papers.

"We need to pay attention to these problems, and try to find ways to deal with them," Hendryx said in a phone interview Tuesday.

Hendryx, associate director of the WVU Institute for Health Policy Research in the university's community medicine department, is co-author of four new articles examining coal's possible impacts on public health in Appalachia.

The studies found more lung cancer deaths, overall hospitalizations and overall deaths in coal-producing counties compared to other parts of the region and to the nation as a whole.

On Tuesday, WVU issued a news release to call attention to one of the papers.

That study, being published in next month's issue of the American Journal of Public Health, used data from a 2001 phone survey of nearly 16,500 West Virginians. Hendryx and Washington State University researcher Melissa Ahern compared the results to coal production figures, U.S. Census data and Department of Health and Human Resources information.

As coal production in counties increases, they found, so does the incidence of chronic illness.

Residents in major coal counties had a 70 percent increased risk of kidney disease and a 64 percent increased risk of developing chronic obstructive pulmonary disease such as emphysema, the study found. Coal county residents were also 30 percent more likely to report high blood pressure.

Hendryx and Ahern tried to isolate coal's potential impacts by factoring out the influence of other possible causes, such as smoking, obesity and age.

"We've adjusted our data to include those factors, and still found disease rates higher in coal-mining communities," Hendryx said.

In another study, published in the January 2007 issues of the Journal of Toxicology and Environmental Health, Hendryx examined hospitalization patterns in coal-mining counties of West Virginia, Kentucky and Pennsylvania.

That study found that hospitalization for chronic obstructive pulmonary disease increased 1 percent for every 1,462 tons of coal produced in a county. Hospitalization for high blood pressure increased 1 percent for every 1,873 tons of coal produced, the study found.

This month, another study by Hendryx in the journal Lung Cancer reported that lung cancer rates for 2000 to 2004 were higher in areas of heavy Appalachian coal mining, even after figures were adjusted to take smoking, poverty and other variables into account.

That study found 684 excess lung cancer deaths in Appalachia during those years. Most of those, the study said, were the result of other factors like smoking. After adjusting for those factors, the study still found 144 excess deaths over the five-year period, or about 29 per year.

Later this spring, another paper by Hendryx in the new journal Environmental Justice will examine total excess deaths from all causes in coal-mining counties in Appalachia.

After adjusting for other possible factors, coal-mining counties experienced 1,607 excess deaths during a six-year period between 1999 and 2004, Hendryx said. That amounts to about 268 excess deaths per year, he said.

"The incidence of mortality has been consistently higher in coal-mining areas for as long as the Centers for Disease Control rates are available, back to 1979," Hendryx said.

So far, Hendryx's work does not make a direct link between coal industry pollution and the increased illnesses. His studies have not yet examined specific emissions figures, or tried to conduct detailed reviews of how residents might be exposed to such pollution.

More research is needed on such matters, Hendryx said, but possibilities include exposure to coal byproducts such as slurry leaching into drinking water or air pollution effects from mining and coal processing.

But public health officials say that simply comparing the illness data for coal counties to non-coal counties provides a start for more in-depth examination of residents' concerns.

"This kind of study has value, because of its exploratory nature," said Celeste Monforton, a former federal mine regulator who teaches and studies public health at George Washington University. "Interested researchers can take the data and add data of their own and try to figure out what's going on."

In West Virginia, officials from the state Bureau for Public Health referred questions to agency epidemiologist Loretta Haddy, who did not return phone calls or e-mail messages on Tuesday.

Stephanie Timmermeyer, secretary of the state Department of Environmental Protection, wanted more time to review the study before commenting on it, said DEP spokeswoman Kathy Cosco.

State and national coal industry officials said they would review the studies.

"We need to find out the basis for it, and what's behind it all," said Bill Raney, West Virginia Coal Association president.

Hendryx said while coal is a major economic player in the state, the impacts of mining on communities should not be forgotten.

"I think we have to be honest about the effects of coal on communities and not just pretend these things don't exist," he said.

To contact staff writer Ken Ward Jr., use e-mail or call 348-1702.