Levels of the two most toxic 'forever chemicals' in England's rivers have fallen by almost a third over the past decade, according to new data from the Environment Agency (EA). The decline in PFOS and PFOA has been attributed to tighter restrictions on their use following mounting evidence of their harmful effects on human health and the environment.
Significant Reduction
The latest figures, published on Thursday, reveal that concentrations of PFOS and PFOA in English rivers have dropped by 30% and 29% respectively over the last ten years. Levels in freshwater fish have fallen even more sharply, by 49%. "It's brilliant to see how far we have come in the last 10 years," said Dr David Megson, a reader in environmental forensics at Manchester Metropolitan University.
PFAS, or per- and polyfluoroalkyl substances, were first developed in the 1930s in the US and gained popularity for their oil-, water-, and heat-resistant properties, making them ideal for products like non-stick pans and firefighting foam. However, their extreme persistence in the environment earned them the nickname 'forever chemicals'. The earliest types, PFOS and PFOA, were linked to tissue damage in animals and increased rates of serious health conditions such as testicular cancer. As a result, PFOS was effectively banned in the UK in 2010, and PFOA in 2020.
Ongoing Concerns
Despite the decline, thousands of other PFAS remain in use. The EA estimates there are around 15,000 different PFAS, though only about 200 are commonly used. The agency's report acknowledges that uncertainty persists regarding the toxicity of many of these compounds, reinforcing the need to regulate all PFAS as a class rather than individually. The chemicals industry has long opposed such an approach, arguing that there is limited evidence of toxicity for other PFAS and that some are essential for life-saving medical equipment.
The EA is now routinely testing for 60 additional PFAS to map contamination across the country, and earlier this month the government announced it would start monitoring levels in people's bodies. However, the report notes that while concentrations have fallen, the overall amount of these chemicals in the environment is likely unchanged because they break down so slowly; they have simply been diluted and 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," Megson added.
One of the few methods to permanently destroy PFAS is high-temperature incineration, but there are currently only two suitable sites in the UK. As concerns grow, the government has launched a plan to tackle 'forever chemicals', and investigations continue into workers exposed to toxic chemicals in firefighting foam.
