The most lethal form of black-lung disease among longtime Eastern Kentucky coal miners who underwent screening has spiked to the worst level in 40 years, according to research published Monday.
The findings deal with progressive massive fibrosis, a torturous, incurable condition.
They come as the coal industry contests new standards that federal mine-safety regulators say will better protect workers from black lung — something the industry disputes.
Just 15 years ago, the prevalence of progressive massive fibrosis among all underground miners who took part in a federal screening program was 0.08 percent, and it was 0.33 percent among active miners with at least 25 years of service, according to Monday's article by three researchers with the National Institute for Occupational Safety and Health, or NIOSH.
But in 2012, the prevalence among longtime working miners shot up to 3.23 percent in Central Appalachia, including Eastern Kentucky, according to the research. That was the highest level since the early 1970s.
The findings were published in the American Journal of Respiratory and Critical Care Medicine as a letter from NIOSH researchers David J. Blackley, Cara N. Halldin and A. Scott Laney.
Screenings from 1998 through 2012 identified 154 miners with progressive massive fibrosis. Of those, 125 were in the Central Appalachia area of Eastern Kentucky, West Virginia and western Virginia, according to the letter.
"Each of these cases is a tragedy and represents a failure among all those responsible for preventing this severe disease," the researchers said.
Blackley said the findings were especially troubling because the most severe form of black lung was essentially eliminated by the late 1990s.
Breathing coal and rock dust at mines can cause various lung ailments, including black lung and silicosis, which choke off breathing.
Gary L. Caudill, 64, of Letcher County, who worked nearly 35 years in underground mines, has the most severe form of black lung.
Caudill said he first experienced shortness of breath a few years before his legs were mashed in a mine accident in 1995, leaving him disabled. His breathing has worsened to the point he can't walk far enough to go hunting, and gets winded just sitting and talking.
"It destroys you," he said of the disease. "Any little thing, you get pneumonia."
Black lung has been an underlying or contributing cause of death of more than 76,000 miners since 1968, according to the federal government, costing $45 billion in federal benefits to miners and their families. That total does not include deaths from silicosis.
More than 40 percent of longtime miners in some regions got black lung before Congress approved rules in 1969 limiting underground miners' exposure to breathable coal dust churned up during mining.
The prevalence of black lung dropped sharply afterward, dipping to 2 percent in screenings conducted from 1995 to 1999, according to NIOSH.
But it started going back up after that. Screenings in 2005 and 2006 found the disease in 3.3 percent of surveyed miners.
NIOSH also began seeing miners developing advanced cases of the disease at younger ages, and a bigger spike in black lung in Central Appalachia.
In Eastern Kentucky, 9 percent of the miners screened in one NIOSH program from 2005 through 2009 had the disease.
Inhaling too much coal dust is the only cause of black lung among working miners.
That means the increase in progressive massive fibrosis can be blamed only on overexposure to dust or being exposed to dust that is more toxic because of a change in its makeup, or both, according to the NIOSH research published Monday.
Researchers identified a number of possible factors in the increase in black lung during the past few years, including miners working longer shifts; increased mining of thinner coal seams in Central Appalachia, which requires cutting through more rock; inadequate dust-control rules; and failure by coal companies to comply with the rules.
Higher silica content could make dust in mines more toxic.
Safety advocates say coal companies and miners cheat on dust sampling at times by putting dust monitors in the clean-air intake of an underground mine, for instance, rather than at the working face where machines can kick out clouds of dust.
Dust fraud is a problem, according to attorneys for the nonprofit Appalachian Citizens' Law Center in Whitesburg, which represents miners in black-lung and safety cases.
Wes Addington and Evan Smith, attorneys with the center, said Monday it was appalling that there has been such an increase in the most severe black-lung cases.
"This data is truly frightening," Addington said. "A decade ago it would have been unimaginable that we would see rates of severe black lung back up to 1960s levels."
Black lung is latent and progressive, meaning more cases could emerge for decades, Smith said.
"We have noticed that more of our clients have complicated coal workers' pneumoconiosis, but this data shows that we've only seen the tip of the iceberg," he said.
The U.S. Mine Safety and Health Administration put new standards in place this year.
The agency lowered the limit of coal and silica dust to which miners legally may be exposed, required personal dust monitors for miners to provide real-time information on exposure, and made several changes in how companies must monitor dust levels in mines.
Coal companies and industry groups have sued, arguing that MSHA overstepped its authority in adopting the new rules, failed to properly analyze their feasibility, relied on flawed data, and required use of an inferior sampling method and a dust-monitoring device prone to error.
The industry argued that most companies comply with health and safety rules. Regulators could have done more to address the spike in black-lung cases in Central Appalachia with increased enforcement there, rather than imposing new standards on all operators, the industry said in its lawsuit.
MSHA estimated the industry's costs to comply with the new rules would be less than the benefits from a reduction in black lung.
"This is further evidence that our efforts to lower miners' exposure to respirable coal mine dust was the right thing to do," MSHA chief Joe Main said of the new findings.