5 days ago
- Health
- The Herald Scotland
Microplastics. Not just bottles. Here's what we should fret about
This week, the world is coming together to thrash out an agreement on the UN Global Plastics Treaty. In a world where plastic production is exponential increasing, this is crucial. Plastics and particularly microplastics, into which these useful and adaptable materials break down, are of increasing concern, and contributing to a global plastic pollution crisis.
At the heart of the concern are microplastics, small pieces of plastic less than 5 mm in diameter. They vary widely in terms of the chemicals associated with them – making assessing their health impact and risk difficult. Increasingly they are everywhere from the placenta of unborn babies to the Arctic - and it's the plastic waste sources we don't talk about that most worry me.
But what is the problem with them? And what do we actually know about their impact on human and planetary health?
1. Research is starting to show microplastic impact on human health
It's still early days in research terms. As the European Environment Agency has put it, 'While much data is available on the presence of microplastics in the environment, knowledge on the health impacts of microplastics is currently lacking.'
But the evidence is gradually building. A recent US study, for instance, found both microplastics and nanoplastics in higher concentrations in placentas from premature births than in those births that went to full term.
Last week The Lancet launched an independent, indicator-based global monitoring system: titled the Lancet Countdown on health and plastics.
'Plastics,' the Lancet report said, 'cause disease and death from infancy to old age and are responsible for health-related economic losses exceeding US$1·5 trillion [£1.1 trillion] annually. These impacts fall disproportionately upon low-income and at-risk populations.'
In a series of letters published last week, titled Act Boldly or Fail, scientists called for 'legally binding targets to cap and reduce plastic production and the phase-out of toxic additives and chemicals in plastics'. They reminded negotiators that the costs of inaction are not abstract, but "can be counted in cancers, reproductive harms, and respiratory conditions".
Dr Cressida Bowyer, Deputy Director of the Revolution Plastics Institute at the University of Portsmouth, said: 'There is clear and growing evidence that plastic poses serious risks to human health. Yet the approach to health protection in the treaty still hangs in the balance. In order to operationalise the global plastics treaty objective to 'protect human health and the environment from plastic pollution' the treaty must directly address human health impacts in the core obligations of the treaty.'
2. In the UK we use, and produce more plastic per capita than average
According to EHA, the global average consumption of short-life plastic per person per year is 20.9 kilograms, but the average plastic consumption per capita in the UK is 31.1 kilograms.
Research by The Big Plastic Count has shown that households are throwing away 1.7 billion pieces of plastic a week—amounting to 90 billion pieces a year.
3. Less than 10% of plastic globally is recycled
That's the figure calculated by an OECD report published earlier in 2022. And in the UK, that rate is looking like 17%.
4. The problem is still growing exponentially.
As the Lancet puts it, production has increased 'from 2 megatonnes (Mt) in 1950, to 475 Mt in 2022 that is projected to be 1200 Mt by 2060.' Alongside that, pollution has risen, with now 8000Mt of plastic waste polluting the planet.
5. Microplastic concentrations are rising in Scotland's seas
Marine Scotland data, obtained in a freedom of information request by the Ferret last year, revealed that the highest concentration of microplastics found in Scotland was in a sample taken from the Solway Firth, where surface water was estimated to contain 210,891 microplastics per square kilometre.
It was also nearly two and a half times higher than the largest sample taken previously in the firth in 2016.
Large concentrations of microplastics in waters were also found south of Tiree (106,453 microplastics per square kilometre), off the East Lothian coast near Dunbar, (81,982 per square kilometre) and in the North Sea oil and gas area of Long Forties (36,304 microplastics in a sample).
Winds of Change on microplastics (Image: Derek McArthur)
6. We've banned some single-use plastic products – but still new items keep coming along
We can celebrate the successes of banning cotton buds and plastic straws, but these plastic items are just the tip of the plastic-berg, with new single-use products always coming on the market, and eventually, hitting our shorelines and landfills. Just last week an open letter called for the banning of the latest single-use scourge, the disposable dental flosser.
7. Microplastics are entering our soil through sewage sludge
One way in which microplastics are entering the environment is via sewage sludge spread on farmland. A study, carried out by the James Hutton Institute and Robert Gordon University, found the prevalence of microplastics in soil was more than 15 times its initial level after four years of sewage sludge application on a farm in North Lanarkshire. The study also found that the number of microplastics in the soil remained relatively unchanged 22 years after application.
8. They are in our food
A University of Catania study found them in a wide range of vegetables, including lettuce, broccoli, carrots, potatoes, apples, and pears, with apples and carrots showing the highest levels. They are also in the fish we eat. A US peer-reviewed study detected microplastics in 99%, or 180 out of 182, samples of seafood in Oregon.
9. They are in our brains
Research, which looked into postmortem samples from brains spanning a period between 1997 and 2024 found that levels were increasing.
10. Our clothes are a major source
We think about plastic bottles, but we don't think enough about the microfibres leaking from our plastic clothes. A University of Leeds report found that UK laundry generates up to 17,847 tonnes of microfibres each year (243g per person), weighing the equivalent of 'around 1,500 double-decker buses'.
11. But so is this rarely talked about microplastic source
But, what's not talked about nearly enough – it sometimes feels as if there is an omerta around the subject – is the biggest source of intentionally produced microplastics, the rubber crumb infill found on artificial turf pitches. This crumb in the UK is chiefly produced from end-of-life tyres.
Earlier this year, Defra published an evidence project report that stated that artificial sports pitches are the main source of intentionally added microplastic pollution in the UK.
According to the Scottish environmental charity, Fidra, 'Each year, thousands of tonnes of microplastics are lost during their use (mainly playing football but also other sports), maintenance, and disposal, ultimately ending up in our drains, soils, rivers, and eventually wildlife.
Though the EU had already announced a crumb rubber ban in 3G pitches to come fully into force in 2013, the UK has not yet followed suit. Responding to the DEFRA report, Professor Andrew Watterson of University of Stirling, criticised the delay.
'The Defra report provided all UK governments with a two year delay on taking similar action to the EU if it wished to follow their lead.'
'It now looks as if those governments will send the report out for wider consultation and further delay."
Prof Watterson said that report appeared geared 'in many respects to weight economic factors highly and downplays externalised costs to wider 'society', sustainability and the need for an effective circular economy". He believes a phase out of 3G rubber crumb pitches is 'necessary and quite feasible'.
12. Recycling may be exacerbating the microplastic problem
Research carried out by Strathclyde University found that the chopping, shredding and washing of plastic in a recycling facility resulted in wastewater. If the results are more widely representative, that would mean that as much as six to 13 percent of incoming waste may be being turned into microplastics.
