PFAS Regulations of Drinking Water in the UK

In recent years, the topic of PFAS (per- and polyfluoroalkyl substances) has garnered significant attention, specifically in relation to drinking water.

PFAS are chemicals found in a variety of household and industrial products. They are often referred to as “forever chemicals”, because they do not break down in the environment. Their persistence in the environment and the potential risks they can have on human health have led to growing concerns about their presence in drinking water.

What are PFAS?

PFAS are a group of over 10,000 synthetic chemicals used in a wide range of products, from non-stick cookware to water-repellent fabrics, and even firefighting foam, since the 1940s. These substances are known for their durability, making them highly resistant to heat, water, and oil. However, this resistance means that PFAS do not easily break down in the environment, meaning that over time they can accumulate in soil, water and living organisms. These chemicals are essentially invisible to human senses which means they are difficult to identify, study and address. PFAS molecules are highly mobile and once they enter the water supply, they can circulate all over the planet.

Why are PFAS a concern in drinking water?

PFAS can enter the water supply through industrial activities, waste disposal, or runoff from contaminated land. Once in the water, they can be ingested by humans, leading to potential health risks. Studies have linked PFAS exposure to a range of health issues, including liver damage, immune system disruption, and an increased risk of certain cancers. Research suggests that children are more sensitive to the harmful effects of PFAS chemicals as they eat more food, drink more water and breathe more air per pound of body weight than adults. The U.S Geological Survey found that over 45% of America’s tap water is estimated to contain PFAS. Due to these concerns, the regulation of PFAS in water has become a priority in the UK and other countries around the world.

PFAS regulations in the UK

To address the potential risks posed by PFAS, the UK has implemented measures to regulate these substances in drinking water. The Drinking Water Inspectorate (DWI) in England and Wales are responsible for monitoring and enforcing water quality standards.

Although no specific statutory limit currently exists for PFAS in drinking water, the DWI has issued guidance to help safeguard public health. In 2021, they recommended a precautionary limit of 100 nanograms per litre for the combined concentration of 20 different PFAS compounds in drinking water. This guidance acts as a reference point for water companies to evaluate and manage the presence of these chemicals. This is in line with guidance from the World Health Organisation (WHO) and the European Union, which have also set strict limits on PFAS in water. However, many experts are calling for tighter regulations in the UK for PFAS, and industry body Water UK wants to see all PFAS chemicals banned completely. 

How are PFAS detected in drinking water?

Detecting PFAS in drinking water requires specialised testing methods, as these chemicals are present in very low concentrations. UK water suppliers are required to carry out regular testing for PFAS, particularly in areas where contamination risks are higher. These tests help ensure that the water meets the required safety standards and that any contamination is addressed promptly.

If PFAS contamination is detected, water companies must take immediate action to reduce the levels of these chemicals. This could involve using advanced filtration technologies, such as activated carbon or reverse osmosis, which are effective at removing PFAS from water. These systems are increasingly being used to provide safe, clean drinking water, particularly in areas with known contamination.