Silicosis Update By Emeritus Professor Odwyn Jones AO and Clinical Professor Bill Musk AM Introduction 1. Crystalline silica is present in many products including sand, rocks, concrete and more particularly synthetic composite or artificial/engineered stone used for kitchen and bathroom surfaces. The is a snapshot of the silica content of engineered stone compared with natural stone: • Marble typically < 5%, but can be more ; Granite 2540%; Sandstone 65-70%; Engineered Stone > 90%. • Exposure to silica dust can cause various diseases (Safe Work Australia, Crystalline silica and silicosis, 2020): Silicosis, chronic bronchitis, emphysema, lung cancer, kidney damage, and scleroderma. 2. The WA Department of Mines, safety alert 11-2018 emphasises: • Effective respiratory protective equipment must be provided in workplaces where there is risk from respirable crystalline silica (RCS). • Workers must be given information, training and instruction with regard to such risks. • Employers must provide workers with health surveillance if there is risk to a worker’s health as a result of exposure to RCS. 3. Work Health and Safety (WHS) Regulation 50 requires that air monitoring by an occupational hygienist be carried out if there is a risk that the exposure limit be exceeded. 4. WHS Regulations also require that health monitoring/ surveillance be an essential part of the control measures. Such surveillance includes a lung function test which, if performed repeatedly, can be a useful measure of progressive lung damage. 5. A well-planned health surveillance system consisting of chest CT scans and lung function tests should be carried out on workers before commencing
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employment and at least every three years thereafter (annually for high-risk jobs) (Cancer Council, 2019).
Workplace standards 1. There’s been considerable discussion recently regarding the adoption of an appropriate TWA standard for crystalline silica: • The mandatory limit for silica dust in Australia has long been a TWA of 0.1 mg/m3 for an eight-hour working day and five-day week. Safe Work Australia (SWA) has introduced a 0.05 mg/m3 standard, but this will not be fully introduced for three years. • Since this announcement, SWA has recommended a further reduction to 0.02mg/m3.
National Taskforce Interim advice was submitted to the Health Minister Greg Hunt in December 2019. The final report is due December 2020. Following are some relevant extracts: • More than 300 diagnosed silicosis cases in Australia since September 2018, due mainly to poor silica dust control in the engineered stone fabrication industry. • WHS regulators must play an active role in enforcing the legal duty of employers to minimise the risks to worker health due to inhaling silica dust: this is a priority.
• All workers at risk of developing silicosis need to be identified as early intervention is critical to minimising harm and maximising good health outcomes. Consequently, a National Dust Disease Registry should be implemented to capture disease notification data. • There is growing support for considering limiting the importation of engineered stone products containing the highest levels of silica. • WHS policy and regulatory practice could be enhanced by integrating epidemiology, occupational hygiene, occupational physician expertise and worker representation. • More communication needed to increase the awareness, knowledge and understanding of all the issues relating to accelerated silicosis amongst workers, SMEs, PCBUs and, in particular small family businesses. • Greater support is needed for those diagnosed with accelerated silicosis, including legal and financial support. • Future support is needed for respiratory and occupational physicians, occupational health nurses and GPs to understand better the increasing incidence of accelerated silicosis. • All jurisdictions need to have consistent and comprehensive health surveillance programs with screening available to all exposed workers.
MEDICAL FORUM | CARDIOVASCUL AR HEALTH ISSUE
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