Microplastic pollution in our streams and rivers
Recent studies have shown that microplastics are having a negative impact on the health of the River Thames and its inhabitants. Scientists at the Royal Holloway University of London have discovered that crabs and other organisms ingest plastics, including the fibres from the outflow of washing machines and fragments of plastic packaging. The quantity of plastic pollution found in the Thames exceeds that measured in other European rivers such as the Danube and Rhine.
In Watlington our chalk stream, the Chalgrove Brook, eventually joins the Thames at Dorchester-on-Thames. Are we in Watlington likely to be contributing, albeit in a minor way, to the problem?
What are the main sources of microplastics found in rivers? One study estimated that synthetic clothing contributes by about 35% to the global release of primary microplastics in the world’s oceans. According to the Royal Holloway University study, on the River Thames, fibres from washing machine outflows and potentially from sewage outfalls, are most commonly ingested by wildlife; but fragments from the breakup of larger plastics are most abundant in the water. Another major source is road traffic emissions from tyres and brakes.
Looking at one of these sources in more detail, washing synthetic clothing, reveals how complex the issue is. A recent study by the UK Water Industry Research shows that sewage treatment works are removing around 99.9% of microplastics. However, even low concentrations passing through could be an issue due to the large volume of effluent discharged. In addition, not all sewage always goes through the full treatment process and instead goes to a storm overflow. Even when the microplastics are removed by the treatment process they end up in the sludge which is put back onto the land as fertiliser. One study showed that textile characteristics, such as the type of fibres constituting the yarns and their twist, influenced the release of microfibres during washing. Also in some fabrics the number of times an item has been washed reduces the microplastics released.
Is there anything we can do? There is a product you can buy called a Guppy Friend – this mesh laundry bag goes into your washing machine. This is the first device developed and marketed specifically to prevent microfibre pollution. The Guppy Friend retails at £25.
So are we in Watlington contributing to the problem and can we do anything? It seems that our everyday activities such as washing our clothes and driving are contributing to the problem but we can take action. There are some simple actions that may have an impact such as wearing more natural fibres, washing our clothes in a ‘guppy bag’, wearing less new clothing, wearing clothes more before washing them and reducing our car usage. Some of these might be actions we choose to take anyway to reduce our carbon footprint.
Jeanette Wooster – Watlington Climate Action Group