What exactly is silicosis and how does it develop?

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Tuesday, 3 March, 2020 - 15:15
Industry news
National News

Regulators around the country are cracking down on silicosis, with the introduction of the new national exposure standard designed to guide employers in protecting workers from silica dust.

Silicosis is an incurable lung disease that results from inhalation of silica dust, said Professor Graeme Zosky, Deputy Director, Menzies Institute for Medical Research at the University of Tasmania.

“When you inhale silica particles they can damage the delicate cells in the lung,” said Zosky, who was speaking ahead of a series of events on silicosis, OHS and the workplace, which will be held across Tasmania from 11-13 March.

“Over time, if exposure continues at a high enough concentration, the cells become overwhelmed and the injury promotes the formation of scar tissue.”

These scars are irreversible and cause changes to the structure of the lung, and Zosky said these changes make the lung stiff and impair gas exchange leading breathing difficulties.

“If the disease is severe it can lead to premature death,” he said.

There are three general categories of silicosis; chronic, acute and accelerated, he explained. Chronic silicosis is the most well-known form of the disease.

This form results from chronic exposure to silica dust over many years and is typically diagnosed many years (typically 10-30) after exposure.

Acute silicosis results from exposure to very high concentrations of silica over a short period of time – and Zosky said it is usually progressive and fatal.

Accelerated silicosis sits somewhere in between chronic and acute silicosis, and Zosky explained that it is associated with high-intensity exposure to silica dust and usually develops within 10 years of first exposure.

“It is usually more progressive than chronic silicosis and is the type of disease that we are seeing in workers exposed to dust from artificial stone benchtops,” he said.

“We know what causes silicosis – inhalation of silica dust.”

The main risk factor is the cumulative dose of silica a worker is exposed to, said Zosky.

“We know that certain activities, such as dry cutting, and other risk factors, such as smoking, may play a role in disease risk but the key issue is minimising exposure to silica dust,” he said.

The Victorian Government recently urged employers to do everything they can to protect workers from silica dust with the introduction of the new national exposure standard.

It also went one step further and urged employers to take a precautionary approach and only expose their workers to levels below 0.02mg/m3.

The Victorian Government has already banned the dry cutting of engineered stone and establishing a health screening program for Victoria’s 1400 stonemasons.

The NSW also announced a new plan to reduce cases of the lung disease silicosis.

On-the-spot fines will be introduced for those who engage in unsafe dry-cutting practices, under the plan, which also includes the creation of a silicosis health register and the introduction of a new workplace exposure standard from 1 July this year.

The NSW Government will make silicosis a notifiable disease, creating a silicosis health register to allow SafeWork to track and investigate the workplaces of those diagnosed with the disease.