Crystalline Silica – The New Asbestos

Crystalline Silica. The new asbestos.

Respirable crystalline silica (RCS) has been touted as “the new asbestos” due to a recent surge of silicosis diagnoses, one of the most common occupational lung diseases affecting workers worldwide. It is believed that this significant workplace hazard could rival the impact of asbestos in coming years as the full extent of the problem is still coming to light. Diagnoses of silicosis in Australia have risen in recent years as news about the condition spreads and more and more workers are getting tested for the potentially deadly disease.

Unlike asbestos which generally impacts workers in their retirement years, silicosis symptoms are presenting in young workers, with the youngest diagnosed in Queensland at just 22 years old. According to the Cancer Council, in 2011, 587,000 Australian workers were exposed to crystalline silica dust in the workplace. Of these workers, it is estimated that 5,785 will develop lung cancer in the future as a direct result of this exposure.

What Contains Silica Dust?

Crystalline silica is a mineral found naturally occurring in many types of sand, stone, rock, mortar and concrete. It is also used in the making of composite (or engineered) bench tops as is found in many kitchens and bathrooms, as well as in tiles, bricks and some plastic materials. Quartz is one of the most common types of crystalline silica.

How much silica graph

Source: No Time To Lose, based on Health and Safety Executive data

Silica dust is created when a material containing crystalline silica is subjected to a mechanical process such as crushing, grinding, drilling, cutting, crushing or polishing. The respirable crystalline silica released is 100 times smaller than a grain of sand, meaning it may be inhaled unknowingly and can penetrate deep into the lungs. Silica dust is 20 times more toxic than coal dust.

Silica dust is 20x more toxic than coal dust

Workers most at risk of coming into contact with silica dust include construction workers, miners, farmers and engineers. Job roles involving crushing or milling material, quarrying, sand blasting, paving, bricklaying, stonemasonry, installation of composite benchtops, demolition, excavation and construction of roadwork have an increased chance of being exposed to silica dust.

What is Silicosis?

Silicosis is caused by breathing in carcinogenic silica dust. When the small particles enter the lungs they cause the formation of scar tissue. This scarring stiffens the lungs and reduces the lungs’ ability to inflate and get oxygen into the system. Those seriously affected may require a double lung transplant. This is an incurable disease and in some cases can be fatal.

Silicosis varies between individuals depending on the level of exposure.

The three types of silicosis

There are three types of silicosis:

  1. Acute – Occurring between a few weeks and a couple years following very high exposure to silica dust.

  2. Accelerated – Occurring after 5-10 years of moderate-high exposure to silica dust.

  3. Chronic – This is the most common type, occurring after 10-30 years of low-moderate exposure to silica dust.

What are the Symptoms of Silicosis?

In the early stages of silicosis, there may be no symptoms. Symptoms may appear any time from a few weeks to many years after exposure. Silicosis symptoms also vary depending on the type of silicosis, but common indicators include:

  • Coughing

  • Phlegm production

  • Fatigue

  • Trouble breathing or shortness of breath

  • Loss of appetite

  • Weight loss

  • Bluish discolouration of skin or lips

These symptoms often worsen over time and lead to an increased risk of tuberculosis, chronic bronchitis and kidney disease. Exposure to crystalline silica can also cause cancer.

If you are experiencing any of these symptoms, contact a healthcare professional.

How to Reduce the Risk

The harmful effects of crystalline silica have been known for a long time, but the recent spike in silicosis diagnoses is thought to have been brought about by a trend of severe malpractice relating to safety measures within high risk industries. Not having the correct Personal Protective Equipment (PPE) such as respiratory protection, dry cutting the increasingly popular composite stones, as well as having inadequate tools, working environments and ventilation has contributed to the increase.

Over an 8-hour time weighted average, Safe Work Australia have determined that the workplace exposure standard regarding the inhalation of silica must not exceed 0.05mg/m3. Controlling the level of exposure to silica dust is key to preventing silicosis. High risk workplace activities should be identified and a plan created to eliminate or control the dust as much as possible. Workers must be made aware of the hazard and trained in the correct procedures to minimise the risk of exposure.

The amount of silica dust inhaled during an 8 hour period must not exceed this amount.

The amount of silica dust inhaled during an 8 hour period must not exceed this amount.

Source: Workplace Queensland

To reduce the hazard of silica dust in the workplace;

  • Where possible, use alternative materials that contain a lesser percentage of crystalline silica

  • Have correct signage around the workplace to notify workers of the presence of silica dust in affected areas. This signage will clearly warn of the danger of silica and state any protection (respiratory or otherwise) that must be worn before entering the area

  • Operate in areas with proper ventilation

  • Reduce the likeliness of dust becoming airborne by using water or dust extraction equipment

  • Conduct air monitoring to measure the levels of exposure to determine whether practices are adequate. This may be done by an occupational hygienist taking air samples regularly to measure air quality and compare against a baseline

  • Wear a properly fitted particulate respirator such as a Powered Air Purifying Respirator (PAPR). Wearers must be clean shaven for the respirator to form a proper seal. Recurrent fit testing of respirators is essential to ensure the correct fit so that there is no leakage

  • Do not dry sweep to clean contaminated areas, instead use wet sweeping or a high-efficiency particulate air (HEPA) filter vacuum

  • Wear disposable or washable protective work clothes, shower and change into clean clothes prior to leaving work. Wearing the dusty clothing home will continue the exposure to the dust and can contaminate cars, homes and other work areas, potentially exposing others to the dust

Silicosis is a very serious illness and is preventable with the correct control measures. To find out more information or to discuss protection options for your workplace, contact the team at ATOM Safety.

Featured Posts