UK accused of lagging behind on ‘forever chemicals’

The UK has been accused of failing to act rapidly enough to control levels of so-called “forever chemicals” in drinking water after research found “significant contamination” in London’s supply.

The Royal Society of Chemistry (RSC) said the UK was falling behind other developed nations by not having standards for PFAS levels in drinking water.

Per-and polyfluoroalkyl substances (PFAS) are a group of chemicals, including perfluorooctanoic acid (PFOA), and perfluorooctane sulfonic acid (PFOS) that have been linked to numerous human health problems including cancers. These substances have been widely used since the 1950s in household and industrial products such as non-stick products, stain-resistant carpets and clothing, and fire retardants.

The European Union and the United States have more stringent removal targets for maximum contaminant levels, which the research indicated all samples taken in London would have failed.

Samples were taken in Battersea, Harrow and Heathrow that showed PFOS levels far above what the RSC proposed as a maximum limit. At Harrow, 14 nanograms/litre was detected, which was 1.4 times higher than RSC’s suggested level.

The research was carried out on behalf of a water filtration producer called Bluewater, which uses reverse osmosis to remove traces of forever chemicals.

Reverse osmosis can itself be problematic because it is energy intensive and rejects as waste around one-third of the water as it treats the substances out.

Bluewater’s research analysed samples from locations across the capital for PFOA and PFOS that were found to contain “deeply disturbing” levels of the substances according to research scientist Ahmed Fawzey.

The samples were tested for two PFAS, they showed:

• Battersea: PFOA 2.4 ng/L, PFOS 3.0 ng/L
• Heathrow: PFOA 5.1 ng/L, PFOS 5.3 ng/L
• Harrow: PFOA 3.6 ng/L, PFOS 14.0 ng/L

He said the current thresholds for PFAS are “confusing” and called for a swift re-evaluation of the maximum guideline level from the current 100 nanograms/litre to 10 nanograms/litre.

According to the US Environmental Protection Agency only 20% of PFAS exposure comes from drinking water, with the majority attributed to food.

The head of the Drinking Water Inspectorate (DWI), Marcus Rink, previously told Utility Week that levels of contamination in the UK and the United States are not comparable, and therefore the UK’s approach is appropriate.

Rink pointed to reports that claimed that 50% of the drinking water in the US has PFAS detected. Meanwhile in the UK, analysis of 310,000 samples revealed that 3.8% had a detection and none were above 0.1ug/l in final water.

He called for better toxicological understanding through the formation of a standards board to help determine whether regulation is needed.

Utility Week’s Drinking Water Conference highlighted work being done by the water sector to address this looming concern, however it also shone a light on the work still to be done.

Peter Jarvis, professor of water science and technology at Cranfield University, said research into two of the 200+ plus PFAS compounds are relatively well known, but there remains a vast range that researchers have no information on.

Matt Hill, lead environmental advisor at Yorkshire Water, explained that traditional biological style treatments are more effective at removing PFOS from wastewater than newer style treatments.

However, he warned that PFOS can only be removed effectively using “really expensive drinking water treatment processes” such as pressurised membrane filtration, with granular activated carbon, or ion exchange. These would be prohibitively expensive to apply to wastewater treatment, he added, while calling for bans of harmful substances to control the risk.