Asbestos-contaminated mulch has been confirmed across parks and schools in New South Wales and the ACT, but health risk remains low, according to environmental protection authorities.
But that doesn’t mean risk is non-existent and caution should be taken when near any material containing asbestos, experts say.
The NSW Government’s special taskforce has investigated multiple reports of non-friable asbestos being found in mulch transported to multiple outdoor locations including 5 schools, and sites including supermarkets, hospitals, parklands, residential estates and rail corridors. Reports have now also emerged that sites in the ACT have received contaminated material.
Asbestos is a major health risk. Exposure to tiny asbestos fibres can lead to asbestosis and cancer. While use of the material has been banned since 2003, it is still prevalent in buildings around Australia.
Australia has one of the highest incidence rates of mesothelioma, with 700-800 people diagnosed with the cancer annually.
Along with asbestosis – a non-cancerous but debilitating disease caused by scarring due to asbestos fibres – it’s one of the most common consequences of asbestos exposure.
How much asbestos is too much?
There is no safe amount of exposure to asbestos fibres, but the risk of developing a disease is increased by prolonged exposure.
And not all asbestos carries the same amount of risk.
Friable asbestos, which can be crushed into a powder, is more likely to become airborne, compared to non-friable, structural forms of the material.
“The harm comes from inhaling the fibres,” says Dr Tim Driscoll, former head of Safework Australia’s mesothelioma registry, now at Sydney University’s School of Public Health.
“Asbestosis is a scarring of the lungs, so the lung gets overwhelmed with the level of fibres, it causes a lot of inflammation, the tissue is damaged and basically the scar tissue doesn’t allow any gas exchange, so the lungs don’t work.”
As a rule, the more exposure to airborne asbestos, the greater the risk of developing asbestosis.
That’s not necessarily the same rule for asbestos-related cancers.
“Mesothelioma, lung cancer, and there’s also laryngeal cancer and ovarian cancer,” Driscoll says.
“You don’t need as high exposure to meaningfully increase your risk of cancer, as you do to get asbestosis.
“It’s very, very unlikely that any member of the community or any worker now would get enough exposure to asbestos to get asbestosis, but it is still possible that workers or members of the community could get enough exposure to cause a type of cancer.”
People should be “appropriately wary”
Despite the understandable public concern when asbestos is found in common environments around a major city, the NSW Government considers most settings impacted by contaminated mulch to be low risk.
Only one location has been identified as containing friable asbestos – which is much easier to break down and release fibres.
In a statement, the NSW EPA advised “the best way to reduce the risk associated with asbestos is to prevent the fibres from being released by preventing damage, disturbance, or deterioration.”
Driscoll agrees.
“Risk is directly proportional to exposure,” he says.
“The higher the exposure, the higher the risk and that sounds bad, but conversely it means the lower the exposure, the lower the risk. So whatever people can do to lower their exposure is good.”
He notes that in the majority of cases where non-friable or bonded asbestos has contaminated mulch, “it’s very, very, very unlikely that there are going to be asbestos fibres in the air.”
“It should be taken seriously, people shouldn’t try to work with asbestos [or] dispose of it themselves. If they know there’s asbestos around then they need to get somebody who knows what they’re doing to get rid of it. But having said that, if there’s a lump of bonded asbestos in a park, [people] should just stay away from that.”
The NSW EPA is encouraging people with exposure concerns to contact NSW Health directly, or to report concerns about recycled mulch online.
