Introduction to Forever Chemicals
Water suppliers have been ordered to tackle potentially harmful levels of so-called "forever" chemicals in the drinking water of more than six million people. Forever Chemicals, or PFAS, are a group of thousands of substances used in everyday products. They are persistent pollutants that accumulate in the environment, and a small number of them are associated with an increased risk of some serious diseases.
What are Forever Chemicals?
Forever chemicals have been used extensively since the 1940s in thousands of products, from frying pans to medical devices to school uniforms. They entered the environment – and the drinking water being treated – over time through washing of PFAS products, storm runoff and releases from industrial sites. This could include using PFAS as stormwater filters to leach through landfills or firefighting training areas, where the use of firefighting foam directly and persistently releases chemicals into the environment.
Health Risks Associated with Forever Chemicals
The study of PFAS is an emerging field, but a small number of these chemicals have been found to pose significant risks to human health. Earlier this year, the World Health Organization expressed significant concerns via two specific compounds. It has been classified PFOA as carcinogenic and PFOS as possibly carcinogenic – increasing the risk of thyroid, testicular and kidney cancer. Both substances are now banned.
Presence of Forever Chemicals in Drinking Water
Over the last four years, 1.7 million tests for individual Forever chemicals have been carried out across the network. At least 9,432 of them recorded PFAS levels above the level that could pose a potential threat to human health. If a test result is above or likely to be above this value, the Drinking Water Inspectorate will issue enforcement notices to the water company requiring measures to ensure water safety.
Challenges in Removing Forever Chemicals
The chemistry of PFAS means they don’t break down easily, so even in the event of a ban they will remain in the environment unless they are treated by water utilities. Removing PFAS presents a significant challenge for water companies with conventional water treatment infrastructure. There are technologies such as nanofiltration that are occasionally used by the water industry and could be used on a larger scale, but these involved high costs and huge energy requirements.
Regulation and Guidelines
The Drinking Water Inspectorate has said that water quality remains safe because once a sanction is imposed, water suppliers are required to increase testing, change or increase PFAS treatment, or remove a drinking water source entirely. However, environmental groups and the Royal Society of Chemistry have raised concerns that the UK guidelines are not legally binding and that limits, which are 2.5 times higher than those in the US, should be lowered.
Response from Water Companies and Government
Water UK told that no matter where you are in the country, when you turn on your tap you will enjoy the best drinking water in the world. But speaking to the Today show, CEO David Henderson said the chemicals should be banned given the rising cost of treatment. The government is currently preparing a white paper in response to an independent review, which will include changes to drinking water inspection.
