More evidence today to support the need for the U.S. Mine Safety and Health Administration to tighten its limits for exposure to coal dust in underground mines.
A new study by NIOSH researchers links again exposure to currently legal levels of coal dust to increases risk of contracting emphysema. According to the study, published in the American Thoracic Society’s American Journal of Respiratory and Critical Care Medicine (subscription required):
… The greater the concentration of coal dust in the lungs, the more severe the emphysema.
It goes on, according to a news release:
While the data were collected on miners who worked in the mines before the enforcement of the federal standard limiting legal coal dust concentrations to 2mg/m3 imposed in 1972, the study does have immediate relevance to current occupational safety standards. Even at the current federal standard, a full working lifetime’s exposure would produce a cumulative exposure similar to the levels found in the autopsied miners.
Lead author and senior NIOSH scientist Eileen Kuempel said:
Based on our findings, exposure to respirable coal mine dust for a full working lifetime at the current 2 mg/m3 standard would increase the emphysema severity index by 99 points on average. This provides additional evidence of the need to reduce dust exposures to 1 mg/m3 or less as NIOSH has recommended. Furthermore, miners in developing countries may be faced with exposure levels in excess of those reported here. Thus, the effects of dust that we report are relevant to current conditions in many countries, including the U.S.
In an editorial in the same issue of the medical journal, Dr. Benoit Nemery wrote:
Coal employs over 7 million people worldwide, 90 percent of whom are in developing countries. Coal production has almost doubled in the past 25 years. The environmental and climatic impacts of burning coal are, quite rightly, a source of concern. However, the direct consequences of extracting coal on the health of millions of coal miners must be an equal concern.