Doctors are urging a ban on artificial stone, a popular material for kitchen worktops, following the diagnosis of the first eight cases of artificial stone silicosis in the UK.
Artificial stone, also known as engineered or reconstituted stone, has gained popularity over the past two decades due to its aesthetic appeal and durability. However, its high silica content – over 90 per cent compared to just 3 per cent in marble and 30 per cent in granite – poses a severe health risk to workers involved in its manufacture and installation, according to a new report published in the UK journal Thorax.
“Silicosis is an incurable and progressive stiffening of the lungs caused by breathing in silica that has recently been broken or smashed,” Patrick Howlett, an MRC clinical research fellow at Imperial College London who has studied the relationship between how much silica someone breathes in over their working life and their risk of silicosis, told BBC Science Focus.
“Multiple industries are exposed from mining to pottery to cement work and, most recently, artificial stone workers. With lower exposures over a long period, silicosis may present after decades and progress slowly over several years.
“However, higher exposures – such as those in those working with artificial stone – can lead to aggressive disease presenting after years of work,” he said.
The eight cases, all male with an average age of 34, worked primarily in small companies with fewer than 10 employees. The workers reported inadequate safety measures, including a lack of water suppression during cutting and polishing, insufficient respiratory protection and poor ventilation systems.
“The [artificial stone] market is dominated by small companies in which regulation has been shown to be challenging to implement,” the report authors wrote.
“The cases we present illustrate the failure of the employer to take responsibility for exposure control in their workplaces. National guidelines are urgently needed, as well as work to enumerate the at-risk population and identify cases early,” they added.
Worryingly, silicosis can progress even after exposure ceases, an effect observed in over 50 per cent of cases over an average of four years. The rapid onset and severity of these cases have alarmed medical professionals, who fear a potential epidemic similar to those seen in other countries.
Cases of artificial stone silicosis have been reported across the globe since 2010 – from Israel to Spain, Italy, the US, China, Australia and Belgium. No cases were identified in the UK until mid-2023, however.
In California alone, almost 100 cases were identified between 2019 and December 2023 among workers who cut countertops – a figure thought to represent a gross underestimate by experts. At least 10 people died, with a median age of just 46 years. In those who survive, lung transplants are often required.
California has since adopted new rules aimed at providing “clear and specific requirements” for workplaces and eliminating loopholes for employers.
Meanwhile, as of July 2024, Australia has completely banned the use, supply and manufacture of engineered stone.
In a linked editorial, Dr Christopher Barber of Sheffield Teaching Hospitals NHS Foundation Trust drew parallels to historical occupational health crises such as ‘grinders asthma’ diagnosed in workers who shaped metal forks using rotating grindstones.
“By design, [artificial stone] worktops (like grindstones) have a very high silica content to make them more hard-wearing and durable. Dry processing of [it] … exposes workers to very high levels of airborne silica dust, in many cases two orders of magnitude greater than legal exposure limits,” he said.
The UK is currently reviewing exposure limits for crystalline silica dust, the results of which remain to be seen.
"Considering the availability of [artificial stone] kitchen worktops, the arrival of [artificial stone] silicosis in the UK is one which has been feared by clinicians for some time,” Barber said.
About our experts
Patrick Howlett is an MRC Clinical Research Fellow at the National Heart and Lung Institute (Imperial College London). His current research focuses on silicosis and tuberculosis among small-scale miners in northern Tanzania and lung function determinants of respiratory infection in children.
Christopher Barber has a national profile in occupational and environmental lung disease and is a Medical Adviser to the Health and Safety Executive. He has an established research track record, having published over 50 peer-reviewed publications, and is an Honorary Reader at Sheffield University.
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