Study links hundreds of California quartz countertop workers to silicosis, dozens dead
Research using California data found 592 silicosis cases among countertop fabricators, with 31 deaths and 65 lung transplants, highlighting ongoing occupational hazards despite new safety rules.
A study of California occupational health data spanning more than seven years identified 592 cases of silicosis among workers who cut and polish engineered stone countertops between January 2019 and June 2026. The disease, caused by inhaling silica dust, affected primarily Latino men with a median diagnosis age of 46. Of those diagnosed, 65 required lung transplants and 31 have died.
California’s public dashboard lists 631 silicosis cases and 35 deaths statewide as of early August. The industry is concentrated in the San Fernando Valley, and the state adopted stricter Cal/OSHA standards in 2023, mandating water use, dust-capturing equipment and powered air-purifying respirators. Silicosis also became a reportable condition in June 2025.
"Although silicosis is preventable with reduction or elimination of silica dust exposure, the water-based tools and ventilation systems required to control silica dust are costly to install and maintain, and overexposures can occur even with recommended controls in place," the study notes.
The researchers said enforcement remains limited; in 2024 Cal/OSHA inspected only 85 of more than 1,300 countertop shops, finding 95% in violation of safety rules. Some occupational health experts have called for a ban on engineered stone, citing Australia’s 2024 prohibition and the subsequent development of lower-risk amorphous silica products.
"Protecting workers from further exposure will require a multifaceted approach, including clinicians’ identifying and reporting of cases to public health authorities, improved surveillance by local and state jurisdictions, and policy changes," the study concludes.