Diving into microplastics: What is the impact on health?

Microplastics are everywhere in our water, food, and even our balls. Let’s dig in.

What are microplastics?

The use of plastics (polymers) in our society has increased exponentially since the '50s, however, the term ‘microplastics’ was coined in 2004 to describe the tiny plastic particles first found in the ocean.

Microplastics are largely generated by the uncontrolled physical degradation of plastic waste over time. For a time, the cosmetics industry had the ingenious idea to manufacture ‘microbeads’ (microplastics) for personal care products but thankfully, these began being phased out in the 2010s.

Particles can be as small as 1 micron — which is tiny compared to a human red blood cell at 7-8 microns — so it’s no surprise we’re finding them in our bodily tissues.

Beyond microparticles, common chemical additives in plastics have also had alarming consequences. BPA (bisphenol A) and phthalates are toxic endocrine-disrupting chemicals that leach into the environment and affect the health and fertility of many life forms.

Where are microplastics commonly found?

Unless you’re moving to Mars with Elon, dodging microplastics is near impossible. They’re in the water we drink, the food we eat, the air we breathe, and the clothes we wear!

Some common sources of microplastic exposure:

• Water: 81% of 159 global tap water samples contain microplastics [1]

• Food: If it’s in the water then it’s in our food and processed food is the worst [2]

• Food packaging: Even food packaging (incl. kitchen wrap) can break down during use [3]

• Coffee cups: Takeaway coffee cups are lined with polyethylene and release microplastics on exposure to hot liquids [4] — no matter if the cup is ‘eco’ from plant-based polymers

• Canned drinks/food: Even cans are lined with plastic to prevent corrosion [5]

• Synthetic clothing: Fibres are shed from synthetic fabrics during wearing and washing

• Personal care products: Microbeads in exfoliating scrubs and toothpaste

• Vehicle tyres: A major source of microplastics in our urban environments comes from tyres [6]

• Plastic litter: The most obvious source of microplastics (environmental degradation of plastic waste)

How harmful are microplastics?

Microplastics can bioaccumulate and have been detected in numerous human samples including the lungs, liver, spleen, placenta, blood, sputum, colon, saliva, faeces, urine, semen and now testes.

Microplastics can increase physiological stress, cellular damage, inflammation, oxidative stress, and immune responses which have been implicated in disrupting the following systems:

• Reproductive: Decreased fertility, gonadal damage and reduced offspring weight in animal studies [7]

• Hormonal: Endocrine disruptors (BPA and phthalates) can result in decreased testosterone levels and alterations to both adipogenesis and energy production [8][9]

• Genotoxicity: DNA damage observed from polystyrene nanoparticles [10]

• Gastrointestinal: Promote inflammatory bowel disease and microbiome disturbances [11]

• Lungs: Associations with lung cancer, asthma and hypersensitivity pneumonitis [12][13]

• Immune: Accumulation of bacteria and other microorganisms on microplastics as biofilms are potential vectors for infection [14]

• Blood: Associations between long-term plastics exposure (specifically styrene) with leukaemia and bladder cancer [15]

• Skin: Allergic reactions and contact dermatitis [7]

They can even induce epigenetic changes, which may span generations [16].

Our understanding of the breadth and severity of the impact of microplastics is still emerging. Most existing evidence is based on animal studies [11] or sub-optimal retrospective human studies [17]. However, it is reasonable to be concerned about what we are learning.

So, what can we do about microplastics?

Here are some practical tips to reduce exposure.

• Underwear: Replace stretch boxers with 100% cotton as we all know it can get hot down there

• Gym gear: Get hot and sweaty in natural fibres instead of microplastic-prone gym shorts and singlets; Ryker was one of the first brands to go after this space but there are many others now

• Coffee cups: Take <5 mins to have your coffee in a mug at the cafe or bring a KeepCup

• Packaged foods/drinks: This is one of the hardest to avoid as everything is in a package at the supermarket these days (even avocados!) but it’s good to be mindful of it where possible

• Water filter: Install a high-quality water filter (ideally reverse osmosis plus re-mineraliser)

• Air purifier: Regularly clean and ventilate living spaces to reduce airborne microplastics

• Natural carpet: Go one step further and remove synthetic fibre carpets [18]

• Natural bedding: Cotton/linen sheets plus wool underlays and natural duvet filling (I prefer wool duvets for better thermoregulation and moisture-wicking properties vs. duck down)

There’s a whole movement around reducing plastic consumption but it’s best to start with the most practical changes before we decide to go off-grid in the bush.

Microplastic detox?

There’s no ‘microplastic detox protocol’ with reasonable evidence yet. Perhaps it will include strategies such as probiotics [19], chelating materials [20], and antioxidants [21] but it’s too early to make recommendations outside of avoidance.

Nevertheless, expect plenty of snake oil to emerge as we all become more concerned about microplastics.

This post contains general information about health and wellness practices. It is not intended as medical advice and should not be treated as such. Please consult with a healthcare professional before starting any new health regimen. This information is provided without any representations or warranties, express or implied.