CALIFORNIA — More than 550 workers in California have received a silicosis diagnosis linked to engineered stone. At least 100 of these workers have undergone or are awaiting a lung transplant, and 30 died between 2019 and 2026.

Engineered stone is a synthetic product comprising up to 95% finely ground quartz combined with polyester resins and pigments. Workers who cut, grind, and polish these countertops risk developing silicosis, a disease for which there is no cure. Studies suggest that 20% or more of workers exposed to engineered stone may develop silicosis. The median age for diagnosed workers in California is 46, and the median age at death for these workers is 52. Silica causes both respiratory disease and lung cancer.

Cases of silicosis among countertop fabrication workers appeared in the United States in 2014, with cases also emerging in Australia in 2015. In 2019, the Centers for Disease Control and Prevention reported 18 cases of silicosis from working with engineered stone across California, Colorado, Texas, and Washington.

In 2016, the Occupational Safety and Health Administration reduced the allowable level of workplace exposure to airborne silica dust. In 2024, a 36-year-old worker with silicosis was awarded $52 million in the first silicosis case related to engineered stone to go to trial in the U.S. Ikea stopped selling engineered stone countertops in 2025. Home Depot, Lowe's, and Costco were selling crystalline silica products as of June 2026. An estimated 100,000 workers are employed in countertop fabrication shops in the U.S.

No independent assessment was available for this report.