PFAS - the 'forever chemicals' in drinking water
PFASs summarise a group of over 4,500 industrial chemicals. They are extremely stable and long-lived, accumulating and persisting in the environment for decades, if not centuries. Meanwhile, they can be detected even in the most remote areas. Experts speak of “forever chemicals”. They enter the human food chain. The consequences for human health and the environment cannot yet be estimated.
In human blood samples, quantities of PFASs are already found that are considered harmful to health. 98 percent of US citizens have PFAS in their blood, the value for Europe is not fundamentally different. In Germany, too, every child already has the forever chemicals in their body; one fifth even in such high concentrations that limit values are exceeded.
Extensive research by the Süddeutsche Zeitung, WDR and NDR together with other European media now show the extent of environmental pollution for the first time. The “Forever Pollution Project” has located more than 17,000 sites across Europe with relevant PFAS pollution – 1,500 sites also in Germany.
One of the well-known examples of PFAS contamination is the Ältötting region in Upper Bavaria. There, PFOA was produced in the chemical park in Gendorf. Although production has been closed down 15 years ago, the substance can still be found in soil, groundwater and the blood of local residents.
Although the hazardous nature of PFAS chemicals is known since a long time, there are still no mandatory rules in Germany for the disposal of PFAS in water, air or soil. There are also no limit values for groundwater and drinking water so far. NDR, WDR and “Süddeutsche Zeitung” (SZ) asked more than 150 regional water suppliers in Germany whether they test their water for PFAS. While a few test their water for the chemicals, the majority does not test for PFAS at all, because there is no legal obligation to test. Without a corresponding obligation, there is also no systematic control.
The upcoming update of the German Drinking Water Ordinance in 2023 provides for the first time binding limits for four substances of particular concern in the PFAS group in drinking water, but these will not apply until 2026 at the earliest. Only then will drinking water suppliers nationwide treat the water with a further purification stage (e.g. with activated carbon), with the help of which the PFAS in drinking water can be successfully reduced. Today, very few water utilities have such a cost-intensive purification stage.
What is particularly absurd is that while water suppliers will have to comply with limit values in the future, there are still no such limit values for the group of substances in industrial wastewater and exhaust air. This means that the substances can continue to enter the environment and thus water and soil unregulated. In the “Forever Pollution Project”, the media also show how industry is fighting a ban on the substances with all means at its disposal.
Reducing PFAS in drinking water
Even though it is not yet possible to make a serious general statement on the filtration of PFAS from drinking water, it is clear that activated carbon binds the chemicals and thus reduces them. Therefore, in addition to its membrane filter systems, Seccua also offers a Seccua biofilter, which is filled with granular activated carbon. The pollutants are not removed from the water mechanically, but through the physical-chemical process of adsorption (binding), in which the substances accumulate on the surface of the activated carbon. The new optimised model of the Seccua biofilter, which will be available soon, will have an even larger activated carbon volume and surface area and thus an even better filtering performance to effectively reduce pollutants such as PFAS. In addition, Seccua offers the new under-sink filter Seccua MK7, which is simply installed under the sink and also reduces PFAS with its purification stage of activated carbon, thus ensuring safe and clean drinking water.
The time when the filter modules have to be changed depends on the local contamination of the respective tap water. An exact durability is currently being determined by tests and also depends on the individual case, as not only PFAS, but the total sum of all pollutants must be taken into account. With the MK7, a change is necessary after 5,000 litres or six months.