A Griffith University study found childcare services at the top of their list of environments dense with airborne microplastics. Next came the office, then schools, then aged care homes. As well as being a science journalist, Heather Gallagher works in this plastic ‘soup’ as an educator. She wonders how all this plastic will affect society’s most vulnerable.
As an educator with an Outside School Hours Care provider, my uniform is a neon green plastic vest. I serve toast to children on plastic plates and milo in plastic cups. Together we play Connect 4, LEGO, Stickle Bricks, chess – all containing plastic pieces.
The children’s favourite craft activity is using Hama Beads. These are tiny plastic rings, placed on a plastic tray, to make pictures that are melted together with an iron so they can be kept ‘forever’. Plastic is everywhere.
What are microplastics?
The thing about plastic – what makes it so useful – is that it is pretty much indestructible. Over time, plastic doesn’t break down, it breaks up. This is how microplastics are formed and pollution follows, getting smaller and smaller over hundreds or even thousands of years.
As the name implies, microplastic is any piece of plastic less than 5mm in length. Microplastics come from many sources including degraded single-use plastics (think plastic bags and straws), synthetic clothing, tyre debris and resin pellets used in manufacturing.
Then there are deliberately manufactured microbeads, tiny plastic fragments, which are used in many personal care products, including sunscreen.
Sooner or later, a lot of these billions of plastic fragments wind up in our waterways, harming wildlife and marine animals. It doesn’t stop there.
Scientists have found microplastics in human lung cells, faeces, body fluids, placenta and breastmilk.
Plastic soup is the air we breathe, the water we drink and the food we eat. A University of Newcastle study estimated that the average person ingests 5g of plastic every week; the equivalent of a credit card.
On the inside
Dr Amanda Dawson has studied the impact of microplastics on fish. The good news, from the analytical chemist’s perspective, is that while sea creatures ingest plastic, it’s restricted to their stomachs and expelled through their faeces.
Humans, however, have multiple exposure points.
“We ingest a lot, but we breathe in a lot more,” says Dawson. “A lot of chemicals that come from plastics aren’t food-safe because they’re not supposed to be eaten. For example, your jumper isn’t made from food-grade plastics because you’re not expected to eat your jumper. But you still ingest plastics from it. We’re getting little microdoses of chemicals with everything.”
She says it’s almost impossible for humans to avoid consuming microplastics.
“As you touch surfaces with dust you end up with plastics on your fingers. Then maybe you touch your mouth. This happens more with young children, but as we have learnt from COVID – adults seem to touch their face a lot too.”
Last year, Norwegian scientists released the PlastChem State of the Science on Plastic Chemicals report, identifying more than 16,000 chemicals in plastic. At least 4,200 of these chemicals – more than a quarter – are hazardous to humans and the environment. The presence of these chemicals in everyday plastic products means that we are constantly exposed to potentially harmful substances.
The problem is compounded because, as they break up, plastics leach unknown substances and contaminants.
Co-author Dr Zhanyun Wang from the Swiss Federal Laboratories for Materials Science and Technology says while the problem is daunting, there are ways forward. There is, he says, “a feasible way towards chemically simpler and safer plastics. Simplifying plastics is critical for moving towards a safe and sustainable circular economy.”
This does not necessarily confirm the relationship between the ubiquitous presence of plastic and poor health outcomes. More study is needed to determine exactly what plastics are doing to us.
And everyone seems convinced that whatever it is, it’s not great.
Are microplastics causing a new public health crisis?
In a bid to quantify the problem, a citizen science project, the Australian Microplastic Assessment Project (AUSMAP), was formed in 2018. The project, coordinated by the not-for-profit Total Environment Centre and co-founded by Macquarie University, has a mission to count and map the plastic that ends up on freshwater shorelines, such as wetlands and estuaries, and on Australian beaches.
With more than 9,000 volunteers involved since its inception, AUSMAP has identified more than 40 hotspots around the country. Of greatest concern are waterways impacted by run-off from synthetic turf and resin pellets released by manufacturers.
Research director Dr Scott Wilson explains that after locating microplastics, they work with their university partners to test their chemical composition and determine ecological risk and then work towards finding the source of the pollutants.
“Until we count and quantify the levels, we won’t really understand how bad the problem is. And that’s what AUSMAPs been trying to do, raise awareness on the issue and to do so with meaningful data.”
He says AUSMAP is creating a library of microplastics so they can compare chemical compositions and their effects over the years.
“When we first started, we tested for heavy metals and pesticides, but new chemicals are now raising their heads,” he says.
“Plastic is now in our bodies prolifically, across all organs and tissues.”
Australia’s microplastic hotspot
AUSMAP have discovered that Adelaide’s Barker Wetlands has the dubious honour of being the worst offender in the country. Recent samples found more than 796,000 pieces of microplastic per square metre in the parklands. The location is home to 130 bird species and other animals including the vulnerable Murray short-necked turtle.
Much of the pollution has been traced to a plastics recycling factory in nearby Kilburn.
But the situation is complicated. The factory, Recycling Plastics Australia, recently received $20 million in government funding to divert 14,000 tonnes of soft plastic from South Australian landfill.
The project, a partnership between the federal and South Australian governments, is among the first announced under the new Recycling Modernisation Fund Plastics Technology stream. It’s part of a push to increase Australia’s recycling and recovery rates for hard-to-recycle plastics and drive a transition to a safe circular economy.
The South Australian Environment Protection Authority says the wetlands were built in the 1990s to address the run-off from the factory.
“Stormwater enters the wetlands at several points, then is filtered through a series of lagoons before discharging, through a sea wall, into the mangrove estuary of North Arm Creek,” a spokesperson says. “Most of the pollutants being washed off the urban catchment are treated and/or substantially retained in the system, which reduces potential impacts in the marine environment.”
But the Total Environment Centre, which auspices AUSMAP, refutes the claim.
“There are no interception traps at facilities or even monitoring,” says TEC executive director, Jeff Angel. “At AUSMAP, we believe that action at the source to filter out microplastics from the industrial area and urban runoff in the catchment needs to be taken, rather than filling up these wetlands with plastic pollution.”
He quoted a recent Austrian study in the peer-reviewed journal Chemosphere that found cancer cells retain plastics more than other cells.
The study examined the relationship between microplastics and four types of colorectal cancer.
“Our observations underscore the potential of MNPs as hidden catalysts for tumour progression, particularly through enhancing cell migration and possibly fuelling metastasis,” the study says.
Meanwhile, the EPA spokesperson says, “to-date the EPA has not undertaken assessment of pollutants entering these constructed wetlands”.
The P.E.R.T.H trial: a world-first study
Professor Michaela Lucas and her team from the University of Western Australia have been trying to determine the long-term impact of plastics on our health.
The world-first study is still unfolding, but began this year with Perth-based scientists examining the health impact on a test group of people who removed plastic from their lives for a week.
The P.E.R.T.H (Plastic Exposure Reduction Transforms Health) Trial recruited 200 healthy adults aged between 18 and 60 to participate
This was narrowed down to 60 participants, with one control group and four intervention groups.
The control group made no changes to their lives while the four other groups spent a week without plastic-wrapped or packaged food, with no plastic utensils or chopping boards and eliminating personal care products that contained plastic.
Lucas was optimistic that removing plastic from the subjects’ lives might lead to better health outcomes.
“Plastic chemicals are everywhere – in the air we breathe, the food we eat, and the products we use daily,” Lucas says.
“What we don’t yet fully understand is how these plastic polymers and plastic associated chemicals might be contributing to rising rates of chronic conditions such as obesity, heart disease and type 2 diabetes.”
Part of the trial was to determine whether it’s even possible to live plastic free.
“Not only is it difficult to live plastic-free but it’s also expensive,” Lucas says. She says cutting out plastic inflated an average weekly grocery bill from $300 to between $1,500 and $2,000.
To cut plastic out of the food chain, scientists provided participants with new cookware and utensils and wooden chopping boards. Food was delivered in glass jars and meat was wrapped in paper.
“It had a significant impact on their lifestyles,” Lucas says. “For example, with socialising they couldn’t get takeaway or go out. They could really only eat what we provided, and they had to prepare everything themselves. That was another difficulty.”
The trial started with comprehensive medical profiling, detailing each person’s regular plastic exposure. The research team recorded their food preparation and consumption practices, their use of personal products, including soap, shampoo and makeup and their environmental exposure. Did the person drive or ride to work? Was their house carpeted (traps more plastics) or not? Did the participant drink alcohol? Microplastics are found in wine that is sealed with plastic-lined screw caps.
Subjects also had their body composition, BMI and waist circumference recorded. And blood and urine were tested for baseline plastic levels.
Lucas says part of the study was aimed at learning what behaviour leads to plastic exposure and how to reduce it.
“We’re very excited by the quality of the data we’ve gathered,” she says. “Hopefully with this level of plastic reduction exposure data we’ll be able to show better health outcomes.”
A global plastics treaty
Australia is one of 65 countries that are part of the High Ambition Coalition to End Plastic Pollution by 2040. The second part of the fifth and final session of the Intergovernmental Negotiating Committee on Plastic Pollution, hosted by the United Nations Environment Programme, is taking place in Korea in August.
The High Ambition Coalition has three strategic goals – to reduce and restrict plastic consumption, to create a circular economy for plastics that doesn’t impact on human health, and to ensure plastic recycling is not environmentally harmful.
Watch this space. And excuse me, I’m off to iron some Hama Beads.