The menace of microplastic

Plastic is not so fantastic as new evidence reveals microplastic could be entering the human food chain. 

If you’re reading this while drinking a cup of tea then you might be interested to know that an estimated 11.6 billion microplastic particles are released into a mug of tea from a single plastic-based tea bag, not to mention an additional 3.1 billion nanoplastics, according to researchers from Montreal’s McGill University. Suddenly that cuppa might not taste quite so refreshing. And, as you throw on a jumper for the crisp spring mornings, you may not be aware that every time a jumper is washed – if it’s made with acrylic, as many of them are rather than polyester or cotton – it will, says a study from Plymouth University, release nearly 730,000 microfibres per wash. With a microfibre being anything up to 5mm in length, one wash could produce over two miles’ worth.

While the harm done to the planet by single-use plastic such as carrier bags, bottles and straws has risen in the scale of public consciousness, the pervasive presence of virtually invisible microplastics has not had the same level of attention. But while they both have potentially catastrophic environmental consequences, the implications for human health from microplastics could be far more serious.

Plastic pollutants

What exactly are microplastics? According to the US National Oceanic and Atmospheric Administration, they are pieces of plastic debris less than 5mm in length. They can come from larger items of plastic that have degraded or could have been manufactured to be used as microbeads in health and beauty products, or they might have come from microfibres in clothing.

...an estimated 11.6 billion microplastic particles are released into a mug of tea from a single plastic-based tea bag, not to mention an additional 3.1 billion nanoplastics...

Whether manufactured or as a result of degradation, the potential size of the problem is huge. A study published by the Marine Debris Working Group at the National Center for Ecological Analysis and Synthesis, University of California found that microplastic particles in the sea in 2014 ranged from 15 to 51 trillion particles, which had a combined weight of between 93 and 236 thousand metric tons.

Once in the world's oceans, the tiny plastic particles can be ingested by the smallest zooplankton all the way up to the largest whales, says the UK’s Marine Conservation Society (MCS). The National Geographic has highlighted how microplastics can block digestive tracts, diminish the urge to eat and alter feeding behaviour in aquatic creatures, with some species starving and dying. In turn, it says, the micropollutants within the plastic are toxins that “could potentially be passed into animal tissue and up the food chain to us as seafood customers.” Like the tea bag plastic particles, we could all be ingesting plastic with an unknown impact on our health both in the short and long term.

The impact on human health

At the recent Plastic Heath Summit held in Amsterdam, the University Medical Centre (UMC) Utrecht revealed that when human immune cells recognise and attack microplastics, they die quickly following contact. Potentially this could compromise immune systems leading to increased incidence of diseases like cancer, while digested microplastics could harbour higher levels of bacteria, again compromising health. The chemical additives in the particles themselves may also be dangerous.

...microplastic particles in the sea in 2014 ranged from 15 to 51 trillion particles, which had a combined weight of between 93 and 236 thousand metric tons.

Some organisations however have been considering the health implications at least as far as drinking water is concerned. “Based on the limited information we have, microplastics in drinking water don’t appear to pose a health risk at current levels,” said Dr Maria Neira, the World Health Organisation’s Director, Department of Public Health, Environment and Social Determinants of Health. But we need to find out more adds Neira: "We urgently need to know more about the health impact of microplastics because they are everywhere – including in our drinking water.”

The asbestos of tomorrow

Given the environmental impact and the unknown health consequences, could microplastics be the next big liability risk for manufacturers who are using plastic? For a material with so many advantages in terms of cost and flexibility, it's unlikely that plastic consumption will be eradicated in the near future but could lessons learnt from a previous 'miracle' material help inform today's efforts to reduce plastic use and ensure safer disposal?       

In the late 1800s, asbestos was growing in use particularly in construction where its fire-retardant properties were particularly valued for areas like cladding, insulation and protective clothing, even ending up in talcum powder and toothpaste. It wasn’t until the 1960s however that the true health implications of asbestos were being played out as those exposed over their working lives began to suffer from fatal diseases like mesothelioma. Today, people are still dying from the effects of asbestos and there is evidence that workers in developing countries continue to be exposed to its use. It is not inconceivable to think that microplastics are on the same corrosive path as asbestos.

Awareness is growing

The positive news is that over a hundred years since plastic was first developed, the signs are that the human health dangers from plastic are beginning to be understood. “There is now an increased awareness of pollution and bigger issues like climate change amongst manufacturers,” says Olivia Reynolds, General Liability Underwriter at Hiscox London Market. “So, it’s no surprise that concern around microplastics is also growing but the risk is still far from being fully understood." 

It is not inconceivable to think that microplastics are on the same corrosive path as asbestos.

As a potentially serious risk however, the insurance industry is starting to sit up and take notice. “We insure manufacturers who make plastic products from a general liability perspective. Cover includes pollution protection for incidents like sudden and accidental spills into waterways for example, but there is no specific cover for an issue like microplastic contamination given the journey of microplastics is very difficult to track,” says Reynolds. “But there is the potential that we could see big class action lawsuits start to arise once more is known about the damage that microplastics can do and the traceability of how they got into the environment.”

No room for complacency

Importantly, adds Reynolds, it's key the insurance industry stays close to the research as scientists look at what the likely microplastic implications for human health will be. “We’re continuing to monitor the risk as a potential exposure that could hit hard when and if the science is able to prove a definitive link between human health and the ingestion of microplastics. Meanwhile, none of us can afford to be complacent about what this risk could mean for the insurance industry in the long term.”