Original article published 14.02.2024.
Accelerated silicosis has been associated with work with artificial stone, sometimes referred to as engineered or reconstituted stone, which has become increasingly popular as kitchen and bathroom benchtops.
Silicosis is a fibrosis of the lungs, an irreversible scarring, that results in symptoms including shortness of breath, cough, and weight loss. Disability can progress and result in death. The disease has been associated with exposure to silica dust (respirable crystalline silica or RCS). Silica is a naturally occurring mineral in most rocks to different degrees. For example, marble and limestone contain around 2% silica whilst sandstone, 70 to 90%. Exposure to RCS has been associated with work in mines and quarries, foundries, and in construction. In recent years, silica has been scheduled as a carcinogen, i.e., has the potential to cause lung cancer.
Artificial stone often contains more than 85% silica and exposure to RCS is associated with cutting and polishing, particularly during dry cutting and without adequate and effective exhaust ventilation.
For reasons yet to become clear, the duration of exposure to RCS and the period between the commencement of exposure and the onset of the symptoms of silicosis are considerably shorter among people working with artificial stone than those that have historically been seen in other industries. Of seven cases of silicosis associated with artificial stone in Australia, all were male and between 26 and 61 years of age, and the exposure duration ranged from 4 to 10 years.
In addition to Australia, silicosis cases associated with artificial stone have been reported in Israel, Spain the USA, and Italy. Such cases have not yet, as far as we are aware, been reported in the UK.
The Health & Safety Executive says that research is needed to better understand the toxicity of the dust generated by different types of artificial stone, and also whether there are significant differences between the risks posed by artificial and natural stone products. It reports cutting and polishing a range of different materials, including resin, sintered, and natural stone products inside the HSE’s large dust tunnel facility and have used a wide range of techniques to characterise the dust and fume emitted, analysing by silica content, chemical composition, particle size, particle mass, and shape. The HSE says that the research will better inform risk assessments and the choice of appropriate exposure control measures, such as on-tool exhaust ventilation and respiratory protective equipment.
Meanwhile, on 13 December 2023, the Australian Commonwealth and state and territory governments unanimously agreed to prohibit the use, supply, and manufacture of all engineered stone with the majority of jurisdictions due to commence the prohibition from 1 July 2024. As such, alternatives to the high silica artificial stone will be used.
In the UK, the designation of silica dust as a potential carcinogen means that exposure must be kept as low as reasonably practicable (ALARP). The interpretation of this ultimately rests with the Courts but generally requires dust control measures such as dust suppression through wet cutting, on-tool and local exhaust ventilation, and potentially, personal respiratory protection (respirators or ‘masks’). However, with it being apparent that alternatives to high-silica artificial stone are available and suitable for use in Australia, we wonder whether the adoption of alternatives more widely is reasonably practicable in preventing exposure.
