Workers Health & Safety Centre

Lung disease linked to stone countertop fabrication

Worker sanding a stone countertop
Evidence linking silicosis with workers who cut, drill and polish stone countertops is mounting, but a recent report suggests we need not wait for more evidence to act.     
"We urgently need to identify stone fabrication workers at risk and reduce their exposure to silica dust," says Dr. Amy Heinzerling, Epidemic Intelligence Service Officer, U.S. Centers for Disease Control and Prevention (CDC) and co-author of a recent report entitled Severe Silicosis in Engineered Stone Fabrication Workers. "Employers, public health authorities and health care providers must all work together to address this emerging silicosis threat in the stone fabrication industry."
Silica is a well-recognized occupational hazard in many industries including mining, construction, glass manufacturing, sandblasting and foundry work. The growing concern for workers who fabricate and install stone countertops is the extreme volume of fine respirable silica dust generated during fabrication.
Airborne silica dust is easily inhaled into the lungs causing inflammation and scarring. Over time, this can cause silicosis—an incurable and progressively disabling lung disease. For those exposed to significant amounts of respirable silica, the timeframe from exposure to suffering can be accelerated.

Occupational health crisis

Heinzerling was part of a team of researchers who examined six cases of silicosis from a single stone countertop fabrication company in California, four cases from one workplace in Texas and a single case in Washington State. Seven additional cases from Colorado were also included.  
In 11 of the 18 cases analyzed, workers were under 50 years of age and the disease was defined as severe and progressive. In one case, the worker had performed stone fabrication for just two years. Two of the workers died at age 38 and 36, after working respectively just nine and 13 years in the sector.
All reported working primarily with engineered stone.
“Engineered stone contains a much higher silica content (>90 per cent) than does natural stone (<45 per cent), posing significant risk to those who handle and work with the material,” says Dr. Cecile Rose, who co-authored the report with Heinzerling. Rose, also a professor of medicine at National Jewish Health (Colorado), adds, “We believe there may be hundreds, if not thousands of cases of silicosis among workers in the engineered stone industry.”
A growing body of evidence in various countries, including Australia, suggests this belief has merit. More than 1,000 stonemasons working with engineered stone countertops in Australia’s third most populous state, Queensland, underwent government-initiated health screening over the past few years. One in six have silicosis with even more suffering related respiratory conditions.
In addition to silicosis, the significant burden of illness associated with silica exposure includes lung cancer, chronic obstructive pulmonary disorder, rheumatoid arthritis and pulmonary tuberculosis.

Prevention needed now

State governments in Australia, including Queensland and Victoria, have taken some steps to curtail this health crisis, among other things issuing safety alerts and banning dry cutting and processing. The Queensland government also implemented a mandatory code of practice for controlling silica exposure in October, 2019. The Australian government has accepted interim recommendations from a National Dust Disease Taskforce including the establishment of a national dust disease registry.
Here in Ontario, silica is a regulated as a Designated Substance under the Occupational Health and Safety Act (OHSA). With this, employers are required to carry out a hazard assessment. If found that workers are likely to be exposed to silica and their health may be affected, the employer must develop a comprehensive control program and implement all necessary precautions to ensure that a worker’s airborne exposure to silica is reduced to the lowest practical level and does not exceed the occupational exposure limit (OEL-TWA) of 0.1 mg/m3 (quartz). Measures should include wet processes and dust-capture ventilation and filter systems. 
This control program must also include medical surveillance, procedures to monitor airborne concentrations and worker exposure, along with training for supervisors and workers.
Where a designated substance, including silica, is present in a workplace, Ontario employers must also establish a joint health and safety committee (JHSC)—regardless of the size of the workforce [s. 9(2)(c), OHSA]. This duty has particular relevance to many of the stone countertop fabrication workplaces that are small-scale though no less dangerous than larger operations. The assessment and the development of the required control program must involve the JHSC. Of course, there are specific obligations relating to the certification of JHSC members in order to prepare them to play an informed role.
Despite these significant obligations aimed at reducing exposure, many continue to call on the Ontario government to lower the OEL for crystalline silica to 0.025 mg/m3—the level currently recommended by the American Conference of Governmental Industrial Hygienists and adopted by six other Canadian provinces. Further still, are calls for a targeted awareness and enforcement initiative to ensure stone fabrication employers understand the significant health hazard associated with their business and their prevention obligations set out in law.

WHSC can help

Workers Health & Safety Centre (WHSC) can assist employers in Ontario’s stone countertop fabrication industry with related training obligations, including WHMIS training and Certification for JHSC members.  

Related resources:
Workers are falling ill, even dying, after making kitchen countertops
WHSC silica resource line
WHMIS resources
Research on silica exposure controls finds PPE comes at a cost

To learn more: 
Call:   1-888-869-7950 and ask to speak with a training services representative