592 California workers diagnosed with incurable silicosis from stone countertops

A new report from the California Department of Public Health (CDPH) has identified 592 confirmed cases of silicosis among workers who cut and shape engineered-stone countertops in California, with cases recorded between January 2019 and June 2026. This marks the largest known cluster of the disease in the United States. Silicosis is a progressive and incurable lung disease caused by inhaling respirable crystalline silica, a fine dust released when materials containing silica are cut, drilled, ground, or crushed. Engineered stone, which is popular for countertops, can contain more than 90 percent crystalline silica, making workers who fabricate, finish, or install these surfaces particularly vulnerable. The disease often develops without obvious symptoms, leading to late diagnoses, and can take years to manifest, though high exposure levels can cause rapid and severe illness. The report's co-author, David Michaels, a professor at George Washington University's Milken Institute School of Public Health, stated that the California figures likely represent only a fraction of the national problem, suggesting there may be thousands of additional cases across the country. He urged healthcare practitioners and public health departments to be vigilant and join efforts to stop the epidemic. The National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA) have jointly updated hazard alerts about the dangers of silica dust exposure for workers in the stone countertop industry. California health officials advise workers to inform their doctors about their occupational history, especially if they have worked with engineered or quartz stone, and to seek medical advice if they develop symptoms such as persistent coughing or breathing difficulties. Providers are encouraged to ask countertop workers about their work history and consider testing even in the absence of symptoms. Workers are also advised to ask employers about dust control measures. The outbreak highlights the need for stricter workplace safety regulations and better enforcement to prevent further cases of this preventable disease.