California Silicosis Epidemic From Quartz Countertops Kills 31, Sickens Nearly 600 Workers

A new report has documented a rapidly worsening epidemic of silicosis, an incurable and often fatal lung disease, among California workers who cut and fabricate quartz countertops, with case numbers more than doubling over the past 16 months as researchers warn the true national scope of the problem likely extends far beyond the state.

The report, published August 12 in the journal NEJM Evidence, identified 592 cases of silicosis among quartz countertop fabrication workers in California between January 2019 and June 2026. Of those workers, 65 have required lung transplants and 31 have died. The study was authored by researchers from the California Department of Public Health, the University of California, Los Angeles, the University of California, San Francisco, and George Washington University’s Milken Institute School of Public Health.

According to the California Department of Public Health, the median age of workers diagnosed with silicosis is 46, while the median age of those who have died from the disease is 52, a notably young age range for a fatal occupational lung condition. Men account for 99% of all documented cases, and roughly half of all cases identified statewide were reported in Los Angeles County.

The pace of new diagnoses has accelerated sharply in recent years. According to reporting from Tech Times, the state’s tracked case count grew from 259 cases and 15 deaths as of March 2025 to 592 cases and 31 deaths by June 2026, more than doubling in just 16 months. Amy Heinzerling, chief of the health department’s Emerging Workplace Hazards Unit and the study’s lead author, told a state regulatory hearing in May that officials had identified 85 new cases in just the first four months of 2026 alone, a pace that would represent the fastest single-year rate of accumulation since the state began actively tracking the disease.

Quartz, technically known as engineered stone, has become an increasingly popular material for kitchen and bathroom countertops in recent years due to its durability and resistance to scratching and staining compared with natural stone alternatives. The material typically contains more than 90% crystalline silica, far higher than natural stone, and generates fine, breathable silica dust when workers cut, grind or polish it during fabrication, according to health officials.

Silicosis develops when workers inhale extremely small crystalline silica particles that become permanently lodged in lung tissue, gradually reducing the lungs’ ability to absorb oxygen. The disease is progressive, has no cure, and can only be managed through measures like supplemental oxygen or bronchodilators to ease breathing, according to the Cleveland Clinic. In its most severe form, the disease can require a lung transplant or ultimately prove fatal.

David Michaels, a co-author of the report, professor at George Washington University’s Milken Institute School of Public Health, and former head of the federal Occupational Safety and Health Administration, described the underlying cause of the epidemic in blunt terms. “Workers have been sickened making quartz countertops, a product we do not need,” Michaels said in a statement, noting that safer alternative materials are readily available. He added that the documented California cases likely represent only a fraction of the true national total, since California remains the only state actively conducting population-level surveillance for the disease even though stone fabrication shops operate in every major metropolitan area across the country.

California officials have said they are now pursuing regulatory and legislative action in response to the report’s findings, with the study’s authors specifically pointing to Australia as a model worth following. Australia became the first country in the world to fully ban engineered stone products in 2023, a decision made explicitly to protect fabrication workers from silica dust exposure.

The report’s release comes amid a separate, high-stakes legislative fight in Washington that could significantly affect sickened workers’ ability to pursue compensation. A bill sponsored by Rep. Tom McClintock, a California Republican, passed the House Judiciary Committee by a 16-7 vote on June 3, and would prohibit lawsuits against manufacturers, distributors and sellers of crystalline silica engineered stone products. According to Tech Times, the legislation would affect roughly 500 pending California lawsuits filed by workers who have already been diagnosed with silicosis or who have already undergone lung transplants. Michaels has testified against the bill before the House Judiciary Committee, arguing it would strip affected workers of their primary legal recourse against manufacturers even as some of those same companies continue selling safer alternative products in markets like Australia.

The California epidemic first drew significant medical attention following a 2023 study published in JAMA Internal Medicine documenting a cluster of 52 young, predominantly Spanish-speaking countertop workers who developed severe silicosis in California between 2019 and 2022, prompting the state’s public health department to issue a formal hazard alert warning fabrication workers about the risks and encouraging them to seek medical evaluation.

With case counts continuing to climb and the legislative fight over manufacturer liability still unresolved in Congress, public health officials say the epidemic remains an active and growing crisis, one they argue requires urgent national surveillance and stronger workplace protections to prevent further illness and death among a workforce already facing the disease’s devastating, irreversible effects.