Microscopic plastic shards in our oceans may receive much attention, but these microplastics are becoming increasingly common in places close to home.
Microplastics have been found in the soils of a popular New England running trial, according to a new paper from University of New England researchers. The study area was a walking and running trail in the Dumaresq Dam Reserve. The researchers took samples from the trail around the dam to gain a complete picture and predominantly found microplastics made of polyurethane, polypropylene and polyester.
Dumaresq Dam was Armidale’s primary water supply until 1968. Today, it is a popular destination for hikers, trail runners and outdoor enthusiasts.
The reasearchers suggest these microplastics may have long-term implications for biodiversity and ecosystem functioning around the trail corridors. While microplastics are known to be highly mobile and may be transported hundreds of kilometres through the atmosphere, the lead researcher, Ms Nicola Foster, a PhD student at the University of New England, feels she has a good read on their origins.
“There’s often a buzz about plastics bags causing microplastic pollution because they’re so visible, but everyone forgets about shoes,” Ms Foster said.
“Trail running shoes with soft rubber can be a significant source of microplastics to the environment.”
“Footwear with harder rubber, such as hiking or road running shoes, tend not to contribute as many microplastics.”
The paper discovered the volume of microplastics produced by shoes also varies between the surfaces.
“The surface these shoes are on does make a difference.”
“Soil doesn’t cause as many microplastics to be shed while sloped surfaces and asphalt, bitumen or rock tend to produce more microplastics.”
The Dumaresq Dam is a popular fishing destination, home to Australian bass, English perch and rainbow trout, so there’s a possibility this may impact the native fauna.
“Microplastics can be transported with repeated rainfall.”
With this in mind, they may end up in the dam and impact local fish, but Foster remains optimistic for local fish populations.
“These particles may not cause mortality at current levels of microplastic pollution, but may reduce their resilience in their environment.”
If microplastics are seemingly everywhere, it seems impossible to fight against them, but Foster offers some suggestions.
“Both footwear and clothing are a massive source of microplastics, and we need to contact manufacturers to push for more sustainable products that are low abrasion and less toxic.”
“Even if you wear natural fibres, such as cotton or hemp, these still have additives that can leach into the soil and water, which animals then ingest.”