The Silica-Associated Lung Disease Projects

The Silica-associated Lung Disease Projects

Chief Investigators

Funding

WorkSafe Victoria, 2019
Medical Research Future Fund grant (MRFF)

Estimated completion date

Ongoing

Projects

MonCOEH longitudinal silicosis registries
Accuracy of digital chest x-ray compared to high-resolution CT chest imaging for the screening of silica-exposed artificial stone workers – a paired, blinded study in an Australian cohort
Investigation of the role of artificial intelligence modelling to identify silica-associated lung disease and prognostic variables
Dyspnoea (Breathlessness) in Silicosis Study
Auto-antibodies and inflammatory markers in patients with high levels of silica exposure

Summary

Since 2015, there has been an alarming re-emergence of silicosis in Australia, primarily affecting workers who fabricate and install kitchen benchtops from high silica-content artificial stone materials. Cutting, grinding, and polishing artificial stone can generate high levels of very fine silica dust particles. When inhaled by workers, these particles can cause lung scarring (silicosis), which may require lung transplantation or lead to premature death. Silica dust exposure also increases the risk of autoimmune diseases such as scleroderma, as well as lung cancer.

WorkSafe Victoria has funded free medical assessments available to past and present workers in Victoria's stone benchtop fabrication industry. These comprehensive health assessments have been provided to identify the presence of silicosis and other silica-related diseases. Workers who participate in the screening assessments and workers identified as at risk of silica-associated disease by a respiratory physician in Victoria have been requested to contribute their data to the MonCOEH silicosis registries.

WorkSafe Victoria has commissioned MonCOEH to fill gaps in evidence related to this re-emergence of silicosis around prevalence, burden of illness and risk factors. This evidence will assist WorkSafe Victoria to address occupational health issues in this industry and to inform the advice provided to employers about occupational health and safety obligations.

MonCOEH researchers were also awarded $994,642 in MRFF funding towards silicosis research. This research will use data from stone benchtop industry workers participating in health screening assessments from Victoria. These projects include investigating new methods to assess disease severity and identify indicators of progression, the efficacy of high-resolution CT scans compared with plain chest x-rays to screen workers for early silicosis and the effectiveness of ultralow dose CT scans to detect silicosis and assessing how artificial intelligence can be used to enhance radiological evaluation.

Impact

Victoria has an estimated 1,400 workers in the stone benchtop industry who may be exposed to silica dust through work-related activities. These projects will help WorkSafe Victoria deliver evidence-based advice to employers to support their health through better prevention strategies, improved health screening and early diagnosis. The data captured by the registries may also inform further epidemiological studies into the emerging condition.

Key findings to date

Silica-associated Disease Registry

From May 2019 to November 2023, 1283 workers have agreed to share their medical data with MonCOEH silicosis registries. More than twenty per cent of those workers that consented, 253 workers, have been diagnosed with silicosis. Analysis of the silicosis registries data has revealed a strong association between exposure to dry processing of artificial stone and disease development, flagging the hazardous work conditions many stone benchtop industry workers have experienced. Most workers diagnosed with silicosis had normal lung function test results and no noticeable respiratory symptoms, highlighting the important role of accurate respiratory health screening in driving early detection. The results also raised significant concerns regarding the accuracy of chest x-rays in detecting silicosis; the results show that almost 40 per cent of people diagnosed with early-stage silicosis by CT had a normal chest x-ray. Preliminary results also indicated a high prevalence of detectable antinuclear antibodies, suggesting significant potential for autoimmune disease in this occupational group.

Key outputs

Hoy RF, Dimitriadis C, Abramson M, Glass DC, Gwini S, Hore-Lacy F, Jimenez-Martin J, Walker-Bone K, Sim MR. Prevalence and risk factors for silicosis among a large cohort of stone benchtop industry workers. Occupational & Environmental Medicine. 2023 Aug;80(8):439-446. doi: 10.1136/oemed-2023-108892. Epub 2023 June 16.

Hoy RF, Sim MR. Correspondence on 'Demographic, exposure and clinical characteristics in a multinational registry of engineered stone workers with silicosis' by Hua et al. Occupational & Environmental Medicine. 2022 Jun 23:oemed-2022-108496. doi: 10.1136/oemed-2022-108496. Epub ahead of print.

Hoy RF, Jeebhay MF, Cavalin C, Chen W, Cohen RA, Fireman E, Go LHT, León-Jiménez A, Menéndez-Navarro A, Ribeiro M, Rosental PA. Current global perspectives on silicosis-Convergence of old and newly emergent hazards. Respirology. 2022 Jun;27(6):387-398. doi: 10.1111/resp.14242. Epub 2022 March 18.

Hore-Lacy F, Hansen J, Dimitriadis C, Hoy R, Fisher J, Glass D, Sim MR. Predictors of psychological stress in silica-exposed workers in the artificial stone benchtop industry. Respirology. 2022 Jun;27(6):455-461. doi: 10.1111/resp.14257. Epub 2022 April 14.

Glass DC, Dimitriadis C, Hansen J, Hoy RF, Hore-Lacy F, Sim MR. Silica Exposure Estimates in Artificial Stone Benchtop Fabrication and Adverse Respiratory Outcomes. Annals of Work Exposures and Health. 2022 Jan 7;66(1):5-13. doi: 10.1093/annweh/wxab044.

Hoy RF, Glass DC, Dimitriadis C, Hansen J, Hore-Lacy F, Sim MR. Identification of early-stage silicosis through health screening of stone benchtop industry workers in Victoria, Australia. Occupational & Environmental Medicine. 2021 Apr;78(4):296-302. doi: 10.1136/oemed-2020-106897. Epub 2020 October 28.

Hoy RF. Artificial stone silicosis. Current Opinion in Allergy and Clinical Immunology. 2021 Apr 1;21(2):114-120. doi: 10.1097/ACI.0000000000000715.

Hoy RF, Hansen J, Glass DC, Dimitriadis C, Hore-Lacy F, Sim MR. Serum angiotensin converting enzyme elevation in association with artificial stone silicosis. Respiratory Medicine. 2021 Feb;177:106289. doi: 10.1016/j.rmed.2020.106289. Epub 2020 December 24.