Artificial-stone countertop slabs in the San Fernando Valley. The slabs are loaded with silica, which, when inhaled, can cause silicosis, a deadly lung disease. Credit: Trevor Stamp

Nine months after Public Health Watch, LAist and Univision revealed what’s believed to be the nation’s biggest cluster of silicosis, a deadly lung disease, among fabricators of engineered-stone countertops in Southern California, the U.S. Occupational Safety and Health Administration is launching an enforcement initiative targeting the culprit: powdery silica dust unleashed during cutting and grinding.

In a press release issued Monday, OSHA chief Doug Parker said, “Many workers in the engineered stone industry are experiencing illnesses so severe that they’re unable to breathe, much less work a full shift, because of their exposure to silica dust.” OSHA said it will “focus enforcement efforts on industry employers to make sure they’re following required safety standards and providing workers with the protections required to keep them healthy.”

Industries affected by the new directive are “cut stone and stone product manufacturing as well as brick, stone and related construction material merchant wholesalers,” OSHA said.

Last December, Public Health Watch and its media partners reported that at least 30 workers — mostly young Latino men — who cut engineered-stone countertops in the Los Angeles area had been diagnosed with an accelerated form of silicosis since January 2016 and another 22 had been diagnosed in other parts of California. One of the workers profiled in that story, Juan Gonzalez Morin, died in April at age 37.

Public Health Watch reported in May that California workplace regulators were drafting an emergency rule to address the outbreak and in June that the Los Angeles County Board of Supervisors had approved a motion to ban the sale and installation of engineered stone, also known as artificial stone. The fake-stone slabs, composed of crushed quartz bound by a plastic resin, are cheaper and more durable than natural stone. But their silica content is far higher. When they are cut or ground, they release clouds of silica dust that easily enter the lungs.

In July, Public Health Watch reported that the number of silicosis in California had risen to 77. Like about half of the states, California has its own, federally approved occupational health and safety program. The federal government enforces workplace standards in the other half.