Microcontaminants place a considerable burden on our water courses, but removing them from wastewater requires considerable technical resources. Now, ETH researchers have developed an approach that allows the efficient removal of these problematic substances.

In our everyday lives, we all use a multitude of chemical substances, including cosmetics, medications, contraceptive pills, plant fertilisers and detergents—all of which help to make our lives easier. However, the use of such products has an adverse effect on the environment, because many of them cannot be fully removed from wastewater at today’s water treatment plants. As micropollutants, they ultimately end up in the environment, where they place a burden on fauna and flora in our water courses.

As part of a revision of the Waters Protection Act, parliament therefore decided in 2014 to fit an additional purification stage to selected water treatment plants by 2040 with a view to removing microcontaminants. Although the funding for this has in principle been secured, the project presents a challenge for plant operators because it is only possible to remove the critical substances using complex procedures, which are typically based on ozone, activated carbon or light.