Are we eating plastic?

by Lydia on 24/07/2024 No comments

“Every week you consume a credit card’s worth of plastic.” You may have seen this claim on social media, but is it an urban myth or reality? We’re looking at why it might well be true.

How does plastic get into our food?

Modern-day food packaging is made almost exclusively from plastic – cling wrap, styrofoam boxes, and sachets are just a few examples. As plastic is used the surface breaks up into tiny particles. These are classified by their size. Microplastics are tiny fragments less than 5mm in length (roughly the size of a piece of rice). Even smaller, and invisible to the naked eye, are nanoplastics. These measure 100 nanometers (0.0001mm) or less. To visualise the difference, if a large piece of microplastic were the size of a football, a “large” nanoplastic would be the size of a sesame seed. For the purposes of this article, we’ll call all these fragments “microplastics”. 

Simply opening plastic packaging releases millions of microplastics into the atmosphere and our food.

Certain environments speed up the deterioration of plastic, meaning it releases even more particles. These include heat, such as from a microwave, and fat, grease and acidity from food. Direct contact with food is part of the reason microplastics end up on our plates, but they’re also found in products that haven’t been wrapped in plastic. So how do they get there? 

  • Environment: Microplastics contaminate soil and water. Plants absorb these, or they are ingested by livestock, passing into our fruit, vegetables and dairy products. 
  • Airborne microplastics: Plastic production, use, recycling and incineration release microplastics into the atmosphere, which are then inhaled by animals in the food chain.
  • Agriculture: Water containing microplastics is used for irrigation. Plastic mulch used to suppress weeds is ploughed into the soil where plants and vegetables grow. Even fertilisers are encapsulated in plastic
  • Processing: High temperatures during food processing can increase leaching from plastic equipment. Contact with vinyl gloves worn by food handlers, plastic tubing in processing machines, and the conveyor belt can contribute to the plastic in our meals. 

So one way or another, most of our food and drink contains some level of microplastic. Eating plastic raises serious concerns. But why is this? 

Chemicals in plastic

Up to 50% of plastic, by weight, is chemical additives. These are used to change how plastic behaves – for example making it flexible, hard, heat resistant, or stretchy – or to give it different colours or shine. A staggering 16,325 different chemicals have to date been identified, but the actual number is likely close to 100,000! You’ve probably heard of some already: 

  • Bisphenol A (BPA) hardens plastic
  • Phthalates make plastic soft and flexible
  • Flame retardants make plastic more resistant to heat

A significant portion (26%) of these additives are known hazardous chemicals. These chemicals are linked to issues like reproductive problems, breathing difficulties, increased risk of cancer and behavioural changes

An even larger chunk, 66%, are a mystery – scientists don’t know enough about them to say what their effects could be. Under current regulations, companies are not required to share full information about the ingredients in their plastic packaging. And many of the chemicals present are not even intentionally added – they are by-products of reactions between other additives. 

This is one of the issues with recycled plastic. Melting down and mixing different types of plastic to make a new material creates a complex “cocktail” of unknown chemicals, further complicating our understanding of the health risks.

A large body of independent research shows our constant exposure to the known chemicals in plastic, even at low levels, could pose a serious risk over time. However, the cumulative nature of microplastic exposure makes it difficult to identify the exact chemicals causing health issues. This lack of clarity is an issue for regulators. 

What regulations are there to protect us?

Some regulations are in place to limit harmful chemicals, but these vary depending on location and the specific types of plastic. The current approach relies on risk-based assessment. This means chemicals can be used freely with limited safety information and need to be proven hazardous before they are banned. This can take up to 20 years! It also allows for “regrettable substitution”, where companies can replace a banned chemical with a structurally similar one with a different name. A prime example is Bisphenol A (BPA). It was commonly found in reusable plastic water bottles until it became restricted due to safety concerns. It’s been replaced with other bisphenols, like BPS or BPF which are likely just as harmful.

Chemicals used in consumer goods and packaging should instead follow the precautionary principle. This says chemicals need to be proven safe before they can be used. With this approach, when there is not enough data to establish safety, we assume there may be risks. 

Negotiations for a global plastics treaty are well underway. Microplastics and chemical migration are high on the agenda. Scientists and activists are pushing for greater transparency in chemical use and a global shift towards the precautionary principle. The plastics industry is resisting, claiming the need for “trade secrets”, and saying a risk-based approach is enough. 

Join us in calling for a strong plastics treaty, that protects us against harmful chemicals, by signing this petition. To learn more about what a strong treaty looks like head to the dedicated section of our website.

LydiaAre we eating plastic?

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