Asbestos in Mulch: Tip of the Iceberg

Mulch containing asbestos has now been found at 78 locations in New South Wales including parks, schools, hospitals, a supermarket and also several sites in Queensland, the ACT and now Victoria. Tests are under way at other sites. The growing crisis has prompted a massive investigation and clean-up, particularly in New South Wales where a taskforce has been setup.

Given that asbestos-contaminated fill or soil is a regular hazard that we deal with as environmental consultants, we thought it would be an opportune time to write a post about asbestos in general, the associated health risks and to frame the asbestos contaminated mulch issue in the context of a much wider problem.

What are the Health Risks from Asbestos?

Asbestos is a naturally occurring, heat-resistant fibre that was widely used in building materials from the 1940s to the 1980s. It can be found in either a bonded or friable form.

Bonded asbestos means the fibres are bound in a cement matrix; typically known in the industry as asbestos containing material or ACM for short. ACM sheeting was used for walls, fences, roofs and eaves and is the form we most frequently deal with (comprising broken up fragments). The fibres don’t escape this matrix unless the product is severely damaged or worn.

Friable asbestos, in contrast, can be easily crumbled by touch and was used for insulation around hot water pipes, asbestos rope, loose-fill asbestos (like Mr Fluffy) and previously bonded products that have worn to the point that they crumble easily.

The risk of disease from asbestos exposure is due to the inhalation of fibres. It doesn’t matter if those fibres are from friable or bonded sources.

However, fibres can more easily become airborne, and therefore inhalable, if the asbestos is friable. This means there is an increased risk of exposure if you are disturbing friable asbestos as opposed to fragments of ACM.

Why is There Asbestos in Mulch and is this New?

Exactly how asbestos got into mulch product continues to be contested, however, it is likely that in most cases, it was present in contaminated recycled wood material sourced from building or demolition sites. In some cases, it looks like its presence could also be due to illegal dumping or ‘fly-tipping’ that occurred either before or after mulch application.

Given that asbestos has been detected at so many sites, in many tonnes of mulch, the degree of contamination sourced from recycled product must not be insignificant.

Asbestos contamination of mulch is, unfortunately, not new. Environmental and health agencies have dealt with these situations in the past. All states have strict regulations about removing asbestos products from the green waste stream but, as is happening now, this does not always happen.

Unregulated sources also present a potential risk, so much so that EPA has issued an alert warning people to be wary about buying mulch through online marketplaces.

If bonded asbestos is ‘low risk’, why are they shutting schools and parks?

“Low risk” is not to be mistaken for “no risk” so environmental agencies are obliged to take a very cautious approach – especially when it comes to crowded public spaces like playgrounds and schools.

Moreover, just because it’s mostly the low-risk ACM that has been found in mulch (although in some instances the friable form has also been found) doesn’t mean that will continue to be the case as it could be quite old (at least 40 years) with a corresponding deterioration in the cement bonding leading to potentially more damage and distribution when it goes through the shredder during mulch production.

Even if we assume shredding up of ACM didn’t lead to its deterioration – as appeared to be the case in most of the samples that have been tested to date – the risk of it becoming friable will also increase the more it is disturbed. This could include from heavy weather, such as heavy rain or hail, or from being kicked up by children in a playground.

Tip of the Iceberg

While the mulch in your local park might be a cause for concern, it is important to put the situation in context. Australia has a huge legacy of asbestos products in our built environment, with an estimated one in three Aussie homes containing some form of asbestos. It’s in the eaves, under the floor, in the switchboard, in the ceiling, in garage walls and fences… And while the focus is currently on mulch in the school playgrounds, what about the school buildings themselves? Hundreds, if not thousands, of schools still have asbestos cement walls, eaves and ceilings.

This is a major problem that requires a coordinated, whole-of-government response to deal with. The federal government’s Asbestos and Silica Safety & Eradication Agency (ASSEA) developed a National Strategic Plan which will hopefully be adopted soon so that all asbestos from our built environment can be removed in prioritised order according to risk and disposed of safely. The cost of doing so will be cheaper than the continuing expense of piecemeal cleanups and closures every time the media discovers another asbestos hazard, not to mention the ongoing health costs to the victims of asbestos.

How can Out-Task Environmental Help?

From a due diligence perspective, our team can conduct assessments to identify potential ACM and friable asbestos, determine the extent of contamination and assess associated risks to assist councils, landowners, and property developers in navigating the complexities of potentially contaminated land management.

Contact us today to discuss any asbestos related challenges you are currently facing.