It is the berries that drive Sarah Rhodes crazy.
With enough effort, Rhodes has found she can buy just about any fresh fruit or vegetable without its plastic wrapping – either naked or packed into a brown paper bag.
But not berries. “All our berries in Australia are all in plastic.” Other countries sell them in cardboard boxes, she says. But not here. It drives her mad.
For the past decade Rhodes has been on a journey to try to rid her life of plastic. “I was quite extreme at one point. It’s more moderate now,” she says. She has accepted some things are too hard, or the alternatives don’t yet work well – like shampoo bars. “I would say they are … OK,” she laughs.
Rhodes is motivated by concerns about the environment, but also her own health. She is aware of the evidence showing plastic builds up in our bodies, where it can mimic human hormones.
But do all the changes Rhodes makes, all her efforts, actually make a difference? Does storing food in glass really matter, when plastics are everywhere?
An Australian study published in top journal Nature Medicine earlier this year suggests individuals really can make a difference to their exposure. Some participants in the study cut the levels of certain plastic-related chemicals in their blood by half – in just a week.
“We were surprised,” says principal investigator Michaela Lucas, a professor at the University of Western Australia. “We were surprised by how easy we found things. How easily we could cut it in a week.”
Lucas’ team recruited 211 participants and extensively surveyed them. What had they eaten in the last 24 hours? What soaps and shampoos and deodorants had they used? What’s your floor made of? Do you use teabags (a major source of microplastics) or loose-leaf?
Then they ran urine and nasal screens – and found every single participant was excreting a cocktail of at least six different plastic-related chemicals every time they were tested; 61.8 per cent had detectable levels of BPA – a chemical used in plastic manufacturing – in their nose.
An umbrella review published in 2024 linked plastic-chemical exposure to a wide range of health risks, particularly in children.
There is “lots of evidence” to suggest these chemicals affect our health, says Mark Green, an associate professor in reproductive biology at the University of Melbourne. “Probably the most evidence we have is for bisphenols (like BPA). That’s been shown in large epidemiological studies that it’s an obesegen. It’s adding to the obesity epidemic.”
Australia’s food safety regulator holds a different view – it says the levels of BPA and phthalates (a key plastic-related chemical) in our food are so low they are unlikely to pose a risk to consumers.
In the new study, associations were seen between bathroom products like skin creams and shampoos and plastic-chemical levels.
And each tin can of food eaten each day increased BPA concentrations in the urine by 14.3 per cent. Tins are typically lined with BPA.
But overall, the strongest predictor of plastic-levels in the urine was how much packaged and highly processed food people ate. That’s likely because plastics are used all the way along the food processing path, from paddock to plate. Plastic containers hold food, plastic-coated machines process it, and it is placed in plastic wrap for sale.
“You think you’re buying an organic tomato. But it’s been grown in a hydroponic plastic glasshouse,” says the Florey Institute’s Professor Anne-Louise Ponsonby, whose research has linked BPA exposure to autism.
Confronted with data like that, Lucas’ team realised simply giving their participants food not packaged in plastics wouldn’t be enough. So they embarked on an odyssey to build a plastic-free food chain.
They involved 150 farmers across Australia, asking them to ship food that had never touched plastic. Fragile items had to be shipped wrapped in wool. “We did not just do a little bit – we went all out,” says Lucas. “This highlights the scale of the challenge for normal people.”
For a week, the team replaced some participants’ food with food that had never touched plastic. Others got new plastic-free kitchenware and utensils, and were asked to line their plastic fridge-drawers with paper towels. A third group got low-plastic bathroom goods: deodorant and dental floss, moisturizers and tooth brushes. A final group got all three interventions.
Changing to a low-plastic diet cut phthalate levels in the urine by between 37 and 44 per cent in just a week. BPA levels dropped 51 per cent. Getting rid of plastics in the kitchen and bathroom cut those levels even further.
The study shows ordinary people can cut their exposure to plastic-related chemicals, says Ponsonby.
But it also makes clear the outsized role governments can have, she says. The biggest decreases in chemical exposure were in people who ate food from a plastic-free food chain – something ordinary people can’t do.
A key step: signing a global treaty to cut plastic production, an ambition that faltered last year in the face of opposition from oil-producing countries.
“People can do something, sure,” says Ponsonby. “But governments are incorrect to put all the onus on individuals. Because we can’t control the plastic in the clothes we wear, or in the air.”
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Liam Mannix is an investigative journalist at The Age. Before that, he was national science reporter for The Age and the Sydney Morning Herald.
Contact him via email or Signal (encrypted) liammannix.18
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