From plastic kettles to pans: Simple swaps to cut microplastics from your kitchen

As the global tide of household plastic rises, a quieter concern is growing: the “invisible” ingredients in our meals. Science now confirms that microplastics — tiny particles under five millimetres — and even smaller nanoplastics have permeated our food chain.

They are in the water we pour, the air we breathe and the food we serve. Recent studies have detected these synthetic crumbs in almost every human tissue, including the heart, bone marrow and brain.

Scientists are working hard to establish the exact health dangers they pose. But according to one of Australia’s pre-eminent researchers, enough is now known to say that we all need to reduce our exposure to microplastics.

Dr Elvis Okoffo, of the University of Queensland’s Alliance for Environmental Health Sciences, says: “There is evidence linking the chemicals in the plastics to adverse health impacts. Now we need to understand what the particles themselves are doing.”

The kitchen is one of the major sites of household exposure and Okoffo’s advice is blunt: “move away from plastic in all its forms”.

It may sound like an overwhelming task, but it doesn’t have to be.

“It’s simple and relatively inexpensive to rid your kitchen of plastic,” says Dr Thava Palanisami from the Global Innovative Centre for Advanced Nanomaterials at The University of Newcastle.

Here’s where to start.

Bin plastic kitchen equipment

The first items for the chopping block in the kitchen are plastic chopping boards. Yes, they are used extensively in commercial kitchens because they are hygienic, but they readily shed strands, which you can see as they develop an almost furry surface as the plastic flakes off. Okoffo suggests replacing them with wooden ones.

Bin all plastic cooking utensils, such as spatulas, stirring spoons and flippers. These are easily and cheaply replaced by wooden implements, such as good old wooden spoons, and metal tools like egg flips, slotted spoons and whisks. “Silicon is fine too; it is much more stable than plastic,” says Okoffo.

Plastic storage containers shed plastic as they suffer wear and tear, especially when they are heated in the microwave. “Never heat single-use plastic containers in the microwave, and try not to heat reusable plastic containers either,” Okoffo says. “Heat definitely causes more particles to break free into the food.”

Warming plastic causes polymer chains to expand and contract, and over time this causes surface degradation, tiny cracks and particle shedding, he says. Not even products labelled “microwave safe” can be trusted because this term refers to the structural integrity of the containers not the fact microplastics may leach.

According to Palanisami, the main issue with storing food in plastic containers is that they deteriorate with use. As they are washed and scratched and battered, they release microplastics.

What to replace them with

Store and heat food in glass containers, or ceramic bowls covered with a plate. For items such as school lunchboxes, Palanisami suggests replacing them with stainless steel containers from the $2 shop.

Avoid plastic drinking bottles

All plastic drinking bottles shed particles, whether single-use or reusable, Okoffo says. A Columbia University study in the US found the average litre of disposable bottled water contained more than 200,000 nanoplastic particles.

Reusable bottles also shed, both from the drinking spout and from the bottle itself, again because as they age, they leach particles, especially if you put them in the dishwasher, says Okoffo.

What to replace them with

Stainless steel bottles with silicon spouts. If you want to be ultra-cautious, fill them with tap water that has been filtered because there are plastics in drinking water (though research is still being done on how to most effectively filter them out).

Replace plastic kettles

Okoffo has been studying microplastic release in plastic kettles at the Queensland Alliance for Environmental Health Sciences by boiling water in them up to 150 times. He and his team reported late last year that plastic kettles shed nano and microplastic for their first 50 boils. The amount was highest in the first few uses but still present after 150 boils.

They found the first boil in a new kettle released almost 12 million nanoparticles per millilitre – equating to almost 3 billion particles in an average 250ml cup. After 150 boils, there were still 205 million nanoparticles per 250ml cup. (The team have not studied how much plastic is shed in older kettles, when the plastic is likely to break down and shed again.) Researchers called for consumer warnings on plastic kettles.

Okoffo recommends buying stainless steel kettles instead.

Discard non-stick frying pans

All non-stick frying pans are coated in chemicals, usually PTFE (polytetrafluoroethylene). Dr Amelia Harray, from the University of Western Australia Medical School, says these chemicals can leach into food during cooking, especially if the ingredients are acidic, fatty or contain alcohol.

An added problem with microplastics (as opposed to the plastic chemicals) arises when the Teflon coating is scratched. A Flinders University study has found a single crack can release 9000 plastic particles. The study found multiple scratches can release millions of microplastics.

“There is some conjecture on exactly how many microplastics are released if the pans are scratched, but whether it is one particle, 1 million or 10 million, we don’t want these microplastics in our bodies,” Palanisami says.