Black Lung disease Coal miners

Carole Bass wrote a piece complete with video of an apparent resurgence in black lung disease among U.S. coal miners. Though the cause is not certain, some theories have been proposed. One is that miners are working more hours than they did 20 years ago -- 12- and 16-hour shifts, and 60-hour weeks. The second is that most of the coal that's left in Appalachia is in "thin seams" -- 28 inches or less -- and mining thin-seam coal requires taking up a lot of rock with the coal. That rock contains silica, which can be worse for a miner's lungs than coal.

For more, see Carole Bass, Why Is Black Lung Back?
http://www.newhavenindependent.org/HealthCare/archives/2009/01/why_is_black_lu.html
JoeC (McGruff)