The most severe form of black lung disease is at levels not seen since the early 1970s, according to new data from the National Institute of Occupational Health and Safety.
NIOSH has been testing underground coal miners in Kentucky, West Virginia and Virginia for the disease for 40 years.
In the data letter published today in a scientific journal, researchers say there has been a startling resurgence of complicated black lung.
This is despite federal laws that were supposed to control dust in coal mines and eradicate the disease.
Evan Smith is an attorney with the Appalachian Citizens Law Center in Whitesburg.