FRANKFORT — A West Virginia University professor of public health Monday defended his methodology and conclusions in a study which shows higher rates of self-reported cancer deaths and other diseases in Kentucky counties where mountaintop removal mining occurs.

CNHI News reported last weekend the study by Dr. Michael Hendryx showed higher rates of cancer deaths, life-long asthma and hypertension in Floyd County than in the eastern Kentucky counties of Rowan and Elliott where such mining practices don’t occur.

Kentucky House Speaker Greg Stumbo, who is from Floyd County, and Bill Bissett, president of the Kentucky Coal Association, questioned Hendryx’s study, basing their criticism on both the conclusions and the method of interviewing residents of the three counties. Stumbo additionally pointed out that Rowan and Elliott counties have higher levels of education attainment and per capital income.

In response to questions from reporters on a teleconference Monday, Hendryx said he is confident in his methodology and accounting for other risk factors such as smoking and obesity.

“I think we were pretty successful,” Hendryx said. “We used standard questions which have been used in many, many other studies.”

Hendryx said smokers were not excluded from his study, but using statistical modification, “the effect of smoking is estimated separately.”

Hendryx, as he said in a weekend interview with CNHI, said no direct causal link between the increase in reported diseases and mountaintop removal mining has been established by research. But he said the evidence of higher disease rates near mountaintop removal sites is overwhelming.

Hendryx was also questioned about how reliable self-reporting by respondents may be.

“We did exactly the same process in the mining and the non-mining counties — we asked the very same questions,” Hendryx said. “There’s no reason to believe people in the non-mining areas would give different answers than in the mining areas.”

Hendryx said the interviews with respondents in all three counties were conducted by volunteer college students from mostly Christian colleges on their spring breaks after a one-day training session. Most were associated with a Christian group called Restoring Eden, a Christian organization which works on environmental issues worldwide.

He and others on the call — Floyd County nurse practitioner Bev May and Deborah Payne of the Kentucky Environmental Foundation — said there is sufficient evidence for policymakers to end mountaintop removal because of its health impacts.

Hendryx said more research is needed to establish a direct link or cause, though he said the evidence suggests the cause is from small particulate matter in the air caused by the explosions removing the overburden and exposing coal seams.

To determine a direct cause, he said, more expensive studies which collect environmental samples from areas to study, along with samples from residents of toenails and blood samples, are needed

RONNIE ELLIS writes for CNHI News Service and is based in Frankfort. Reach him at rellis@cnhi.com. Follow CNHI News Service stories on Twitter at www.twitter.com/cnhifrankfort.