Artificial stone countertops contain natural stone, quartz, resins, and Portland cement. The combination of these materials can contain more than 90% silica.1 In contrast, natural stone contains 50% or less silica.2 Artificial stone is desirable because it is lighter and thinner than natural stone, non-porous, and has strong mechanical resistance.3 Manufacturers also market the new material as stain and scratch proof, acid and fire resistant, environmentally friendly, and non-toxic while claiming these materials are indistinguishable from natural stone. Because of its desirable properties, artificial stone is a preferred choice in homes for kitchen or bathroom countertops and in retail and hospitality establishments. Cases of silicosis have recently been associated with the manufacture of artificial stone products, and a discussion of the industry practices leading to these occupational injuries is provided here.
Silicosis refers to a spectrum of pulmonary diseases caused by inhalation of free crystalline silica and is marked by scarring and thickening of the lung tissue which can progress to respiratory failure and death.4 Silica inhalation is the main cause of occupational respiratory disease worldwide,5 and differences in exposure can result in different forms of the pulmonary disease which include acute silicosis, accelerated silicosis, chronic silicosis, and progressive massive fibrosis.6 For example, high-intensity silica exposure is associated with acute and accelerated silicosis with acute silicosis developing within a few weeks to less than 5 years of high-intensity exposure7,8 and accelerated silicosis developing within 10 years of moderate – high levels of exposure.4 Chronic silicosis can develop following decades of exposure to silica dust and even progress after exposure has ceased.4