Silica is a naturally occurring mineral found in various forms like sand and quartz. It is a common element in the Earth’s crust and is used in many products and applications, such as glass, ceramics, and construction materials. While generally non-toxic, inhaling fine crystalline silica particles in large quantities can be potentially hazardous to health, possibly leading to lung diseases such as silicosis, a deadly and incurable disease.
Silica Exposures
What has been described as “one of the worst industrial tragedies in the history of the United States” involved silica exposure.1 In 1930, construction began on a three-mile tunnel through a mountain in West Virginia, the Hawk’s Nest Tunnel. The construction of the tunnel involved drilling through silica-rich rock using a dry technique, releasing hazardous silica dust into the air. Workers, mostly African American men, labored in confined, poorly ventilated spaces without adequate safety measures or respiratory protection. This led to widespread cases of silicosis. Misdiagnosed as “tunnelitis,” the disease quickly claimed hundreds of lives. Of the approximately 5,000 laborers, about 2,900 worked inside the tunnel, and at least 764 died from silicosis, making it the deadliest industrial disaster related to silicosis in U.S. history. Many more died in the years following due to prolonged exposure.2 A congressional investigation and then a “Stop Silicosis” workplace safety campaign led by Secretary of Labor Frances Perkins followed.3
Despite these efforts, silica exposure continued to be a serious health hazard for workers in the construction industry. An early incarnation of silicosis litigation in the 1990s and early 2000s mostly related to alleged injuries and illnesses associated with sandblasting activities. By 2001, a surge in workers’ claims of lung damage from silica dust raised fears that silica could become the next asbestos. In 2003, over 10,000 claims were consolidated in a Texas court. The case revealed widespread diagnostic fraud, and Judge Janis Graham Jack’s harsh 2005 ruling played a key role in dismantling the litigation.4
Engineered Stone Exposures
Consequently, silicosis claims declined significantly until reemerging recently as the renewed popularity of engineered stone is bringing an increase in claims by the tradespeople who work with these products. Engineered stone is a man-made material composed primarily of crushed natural stone (usually quartz) combined with a polymer resin binder and sometimes pigments. It is designed to look like natural stone but offers more uniformity, greater durability, and a larger selection of colors and patterns. The use of engineered stone has increased over the last decade to become the most used countertop material in the United States.5
Unfortunately, the growing popularity of engineered stone has led to serious health risks for workers. Unlike natural stone (granite = 30% silica, marble <10% silica), engineered stone contains over 90% crystalline silica. Cutting and polishing it releases large amounts of silica dust, along with other harmful substances, putting workers at high risk for severe, fast-progressing silicosis.
Regulations
First reported over a decade ago in Spain and Israel, more than a thousand cases of silicosis among engineered stone workers have now been documented globally.6 Furthermore, in response to hundreds of silicosis cases among engineered stone workers since 2015, Australia implemented stricter regulations, certifications, inspections, and education requirements. Ultimately, a national task force determined that dangerous silica dust exposure continued despite these measures. As a result, Australia became the first country to ban engineered stone, effective July 2024.7
The California Department of Health began recording reported silicosis cases among engineered stone countertop workers in 2019. As of March 6, 2025, they have recorded 336 confirmed cases, 19 deaths, and 41 lung transplants.
California Engineered Stone Silicosis Cases – Year Confirmed
Identified by California Department of Public Health