What is it?
Crystalline Silica is a naturally formed mineral found in over 90% of the earth’s crust, used in products such as concrete, brick, pavers, tiles and natural and composite stone bench tops. In its natural form, crystalline silica is not a risk. However high-energy processes such as cutting, polishing or grinding, particularly when dry cutting methods are used, transforms crystalline silica into respirable dust that remains airborne for extended periods of time. This usually occurs during the manufacturing process.

The dust is easily inhaled deep into the lungs and can cause irreversible damage. Anyone working in environments with exposure to respirable crystalline silica (RCS) is at risk.

What are the health effects?

As a hazardous chemical, RCS can cause silicosis, a lung disease that may lead to disability and even death. Whilst the most common presentation, caused by exposure, is a slow progression over many years, some cases have developed from high exposure over short periods of time. Lung cancer, chronic obstructive pulmonary disease and renal cancer can also result from extended exposure to RCS.

What are the symptoms to look out for?

Individuals who are suffering from silicosis may experience shortness of breath, noticed initially on exertion, or sometimes a chronic cough. However, many workers with early silicosis may not experience any symptoms, with an x-ray being the best way to detect the disease.

In rare cases, it can present as a rapidly progressive disease and affected workers may experience shortness of breath, a cough, weight loss, fatigue, and sometimes chest pain.

What action has been taken to date?

Crystalline Silica has been the focus of a recent audit carried out by Workplace Health and Safety Queensland. The compliance audits focussed on engineered stone bench top manufacturers and found multiple instances of workers being exposed to RCS.   Subsequent health monitoring of these workers has identified over 30 workers with silicosis including a number of cases of advanced disease.

All remaining engineered stone bench top fabricators in Queensland will be audited over the coming weeks to ensure adequate dust controls are in place and all other work health and safety obligations are being met. Workplace Health and Safety Queensland has also deemed that all workers in this sector are at risk, and must be provided with health surveillance.

How can exposure be managed in the workplace?

Identify situations in which exposure can occur. Fabricating, and installing natural and artificial stone bench tops can release high levels of RCS through cutting, grinding and polishing processes, particularly when dry cutting methods are used. Workers can also be exposed to RCS from poor cleaning practices including dry brooming of dust, the use of compressed air, using non-H class HEPA filtered vacuum cleaners or by allowing the accumulation of dust within the workplace.

Businesses in this industry must not allow uncontrolled dry cutting, grinding or polishing of artificial / engineered stone bench tops. Measures must be put in place to control dust such as water suppression of dust or utilising equipment where dust collection is part of the design. Measures to prevent exposure from cleaning local exhaust ventilation must also be implemented. Isolating workers with barriers whilst handling RCS or using materials with a lower percentage of crystalline silica are also alternatives.

The government has advised that, based on the monitoring they have recently undertaken to date, there is a significant risk to all workers, and so they have removed the discretion from employers and mandated that all workers in this particular industry sector must have health surveillance.

Can it be treated?

There is no specific proven therapy for silicosis. All patients with radiographic evidence of silicosis should avoid further exposure to RCS, which may require steps to minimise exposure in the workplace, or a change of occupation. Severe cases may require lung transplantation.

The risk of disease is related to the duration and concentration of exposure. The longer excessive exposure is allowed to occur, the more likely that more workers will develop the disease, or develop more advanced disease. It is therefore imperative that steps be taken immediately to limit exposure, and that workers who already have the disease be identified.

How can Sonic HealthPlus assist?

Sonic HealthPlus employs a number of occupational physicians who are experts in diagnosing silicosis and recommending preventive measures in the workplace. We have worked with the Department of Natural Resources, Mines and Energy in Queensland to develop best practice health surveillance for dust disease, and bring that expertise to monitoring for silica.

We provide the following services to assist workplaces in managing exposure to RCS:

• Specialist workplace assessment by occupational physicians who may assist in identifying high risk occupations and tasks.
• Our occupational physicians are available to explain the risk and health effects to your workers in your workplace.
• Providing health surveillance for exposed workers including:
  • Detailed work history.
  • General health questionnaire.
  • Specific respiratory symptom questionnaire.
  • Spirometry, performed in accordance with TSANZ guidelines.
  • Referral for a chest x-ray, reviewed by an accredited ILO reader.
  • High-resolution CT scanning may also be recommended.

For further information, don’t hesitate to contact our Specialist Services Unit for assistance on 1300 588 440.