In 1998, the maximum concentration of micro pollutants, such as heavy metals, drug residues, pesticides and other substances in the water of Swiss lakes and waterways was set at 0.1 μg/litre.
This month Switzerland’s government decided to change this limit, reducing it for some pollutants, but setting it significantly higher for many others.
Among the 38-long list of pesticides, 26 will soon have limits exceeding 0.1 μg/litre. The limits for a few such as glyphosate (3600 times higher), ethofumesate (2600 times higher), and iprovalicarb (1900 times higher) really stand out.
Maximums for some drug residues will be well above the old limit. The allowable concentration of bezafibrate, an anti-cholesterol drug, will soon be 40,000 times the old limit. Limits for carbamazepine (20,000 times), an epilepsy drug, and naproxen (8,600 times), an anti-inflammatory drug, will far exceed to old limit too.
The new limits were calculated by the Centre Écotox Eawag-EPFL based on their effect on aquatic organisms.
The government said that rules related to the use of pesticides will remain unchanged.
WWF Switzerland responded strongly to the news. Specifically in relation to pesticide limits, Daniela Hoffmann, WWF’s agriculture expert said that these changes clearly contradict the main objective of the laws protecting waterways and ignore the precautionary principle, pointing out past failures. In the 1940s DDT, whose insecticide effect was discovered by the Swiss chemist Paul Hermann Müller, was considered harmless. DDT use is now banned across much of the world.
The new limits will come into force on 1 November 2018.