CHARLESTON, W.Va. — The inspector general for the U.S. Department of Labor is urging the government’s mine safety agency to tighten restrictions on a dangerous substance that is inhaled by coal miners.

A report from the inspector general’s office said the Mine Safety and Health Administration, or MSHA, has not done enough to protect miners from exposure to silica dust. It said MSHA has had the same silica standard since the 1960s, according to a report by the Charleston Gazette-Mail. The substance is believed to be a contributor to black lung disease. Read more: washingtonpost.com