Significant drop in levels of toxic ‘forever’ chemicals in England’s rivers

Liverpool's waterfront, with its mix of modern high-rise office blocks and the Edwardian Baroque Royal Liver Building, from across the River MerseyGetty/Peter Chadwick LRPS
Esme Stallard

Senior climate and science reporter

Levels of the two most toxic “forever” chemicals in England’s rivers have dropped by nearly a third over the last decade, according to new figures from the Environment Agency (EA).

The decline in the chemicals, PFOS and PFOA, has been put down to stricter restrictions on their use in products after increasing evidence emerged of their damaging impact on human health and the environment.

One expert studying the impact of the chemicals said it was “brilliant” to see how far the UK has come on this issue.

Thousands of other forever chemicals, known officially as PFAS, remain in use but the regulator said its report showed the need for them all to be better monitored and regulated.

PFAS were first developed in the 1930s in the US and became popular with companies making products like frying pans and firefighting foam because of their useful, oil-resistant, water-resistant and electrical properties.

They are called forever chemicals because their natural resistance means they take a very long time to break down naturally.

The earliest types of these chemicals were called PFOS and PFOA. But two decades ago researchers started to find that they were linked to tissue damage in animals and increased rates of certain serious health conditions such as testicular cancer.

As a result, PFOS was all but banned in the UK in 2010 and PFOA in 2020.

The latest data from the regulator, published on Thursday, shows that the concentrations in English rivers of PFOS and PFOA over the last ten years have now fallen by 30% and 29% respectively.

Levels in freshwater fish have fallen 49%.

“It’s brilliant to see how far we have come in the last 10 years,” said Dr David Megson, reader in environmental forensics at Manchester Metropolitan University.

There are thought to be around 15,000 other PFAS, although only around 200 are frequently used.

The EA said that despite increasing research into these compounds, “uncertainty remains regarding the toxicity of many PFAS”. It said its findings “reinforces the need” for regulating all PFAS rather than one by one.

The chemicals industry has long opposed such an approach, arguing that there is currently no, or limited, evidence to suggest that other PFAS are toxic and that some have vital uses such as in life-saving medical equipment.

The regulator is now regularly testing for 60 other PFAS to build a picture of contamination across the country, and earlier this month the government announced it would begin monitoring levels in people’s bodies.

The EA report acknowledged that while concentration levels have fallen, because the chemicals take so long to break down, the overall amount still in the environment is likely to have remained unchanged – they have simply been diluted and been washed into the sea.

“There is a lot to do, and this report provides an essential foundation to support investigations to make the polluters pay for any damage they have caused,” said Megson.

One of the few ways to permanently destroy PFAS is by high-temperature incineration – there are just two such suitable sites in the country currently.

Related topics

  • Water pollution
  • Environment

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