Appalachian surface coal miners are consistently overexposed to toxic silica dust, according to new research from the National Institute for Occupational Safety and Health, and surface mine dust contains more silica than does dust in underground coal mines.
The research released Tuesday is the first to specifically analyze long-term data on exposure to toxic silica dust for workers at surface mines. The work reveals that while attention has been trained on a surge in disease among underground coal miners, surface miners are similarly at risk of contracting coal worker’s pneumoconiosis, or black lung disease.
Black lung disease has been identified in coal miners in every coal-mining state at both surface and underground mines. NIOSH researchers were specifically interested in surface miners’ exposure because those mines produce the most coal and, in 2017, twice as many miners worked at surface mines compared to underground mines.
Researchers analyzed 54,040 coal dust samples taken on surface mines between 1982 and 2017 to determine the percent of that coal dust that was silica, and found that the level of silica was above the permissible limit in 15 percent of those samples. Silica dust comes from quartz in the rock layers near coal seams, …