PFAS in tap water: safe today, concerns for tomorrow

Greenpeace’s large-scale PFAS campaign [Verbied giftig PFAS – Greenpeace Nederland] became the top news story in the Netherlands yesterday. National media outlets, including NOS News and NPO Radio 1, as well as numerous regional broadcasters, reported extensively on the new online postcode map. As millions of Dutch people discover which “colour code” applies to their tap water, attention is also turning to policymakers, drinking water companies, and the scientific community.

Vewin, the umbrella organisation representing Dutch drinking water companies, immediately issued a clear statement on drinking water quality. Behind the scenes, KWR Water Research Institute has been conducting research for years into practical solutions to the problem. But what does the news about water quality actually mean for consumers, and what solutions are available to improve water quality?

Vewin: “The water is safe, but we are mopping up with the tap still running”

The Association of Dutch Drinking Water Companies (Vewin) responded immediately to Greenpeace’s report. It emphasised that Dutch tap water meets the applicable European legal standards everywhere and is completely safe to drink. This is also confirmed by both the Dutch National Institute for Public Health and the Environment (RIVM) and Greenpeace. Although PFAS concentrations in drinking water exceed the RIVM’s health-based guideline value in some locations (the concentration we would ideally like to achieve), this does not mean that tap water is unhealthy. Unfortunately, PFAS is found everywhere, and there is no guarantee that other beverages are free of PFAS either. Moreover, the amount of PFAS we ingest through food is approximately four times greater. Bottled water has other disadvantages, including a high environmental impact and often the presence of microplastics. There is therefore no reason to stop drinking tap water.At the same time, however, Vewin is sounding the alarm about the future. Because of their properties, PFAS compounds are extremely difficult to remove from water. Drinking water companies are currently investing millions of euros in the development and implementation of costly treatment technologies to remove PFAS. Meanwhile, PFAS discharges continue—and are even increasing. This is not only due to the well-known chemical industry, but also to PFAS that enter the environment through wastewater after being used by consumers, as well as the use of PFAS-containing pesticides in agriculture. This makes it increasingly difficult for drinking water companies to meet the guideline value. The sector is therefore calling for a rapid and comprehensive European ban on the production and use of PFAS. Its position is unequivocal: “What doesn’t go in doesn’t have to be taken out.”

KWR: The scientific facts behind water treatment

While Greenpeace is driving the public debate, KWR provides independent scientific data. Greenpeace’s PFAS map is based on publicly available measurement data that have, among other things, been validated using KWR methodologies. KWR’s work regularly receives attention in the media:

• The pros and cons of household filters: Commercial companies are eagerly capitalising on consumer concerns by promoting household PFAS filters. KWR experts, including Dr Ir Roberta Hofman-Caris, recently concluded, including on the television programme Radar, that these consumer filters are unnecessary. Not only are they generally unable to remove PFAS effectively, they can also promote bacterial growth, potentially posing a much more serious health risk than low concentrations of PFAS. Centralised treatment by drinking water companies is much safer and more reliable.
• PFAS adsorption using activated carbon: Many water companies use activated carbon filters to adsorb PFAS and other contaminants, such as pesticides and pharmaceuticals. KWR and the drinking water companies are investigating how this adsorption process can be improved through their joint Waterwijs research programme. Research has now also demonstrated that PFAS are actually broken down during the reactivation of activated carbon, meaning they do not simply return to the environment.
• TFA as an emerging contaminant: Recent research by KWR and the Human Environment and Transport Inspectorate (ILT) has shown that TFA (the smallest and highly mobile type of PFAS) is already present in 73% of shallow groundwater.
• KWR models indicate that, without intervention, TFA will reach deeper groundwater layers within 20 years—the layers from which most of our drinking water is produced. By comparison, 21,000 kg of TFA enters the Dutch environment through pesticides every year. This quantity alone would be sufficient to raise the concentration in eight times the total annual Dutch drinking water production above the RIVM guideline value.
• Effective removal: Reverse osmosis (RO) is capable of removing all dissolved substances from water, including PFAS. However, there are two challenges associated with using RO. From 1,000 litres of contaminated water, the process produces 800 litres of clean water while leaving 200 litres containing five times the original concentration of contaminants. This concentrate would ideally need to undergo further treatment, with the PFAS preferably being destroyed. As part of the PAK PFAS research programme, KWR is developing specific technologies for this purpose.

The ball is now in the politicians’ court

The extensive media attention has highlighted the tension surrounding the issue. The Dutch drinking water sector has extensive expertise in producing clean drinking water. However, the presence of PFAS in the environment requires a fundamentally different approach—one that presents enormous technical, financial and environmental challenges, including the use of chemicals and energy. KWR’s data and Vewin’s call for action reinforce the attention that Greenpeace is bringing to this issue. The responsibility now lies with the Dutch Ministry of Infrastructure and Water Management and European policymakers to tackle the pollution at its source once and for all.