Nathalie Chèvre was a guest on Radio Télévision Suisse's (RTS) ‘La Matinale’ programme. The French-language SRG broadcaster asked the ecotoxicologist to categorise the results of the investigation by the consumer programme «A Bon Entendeur». Her verdict is clear: «The permitted pesticide levels in water are disproportionate to the toxicological effects». According to the researcher, consumers need not worry when consuming the mineral waters in question. Although harmful substances can be detected in certain drinks, water is perhaps the least of what we are exposed to.

In particular, the study detected substances that are banned in the mineral waters of Henniez, Valser, Swiss Alpina and San Pellegrino. Residues of chlorothalonil were also found. This is a fungicide that was used in agriculture. The EU banned it in 2019. Switzerland followed suit, but Syngenta has lodged an appeal against the decision.

In an interview with RTS, ecotoxicologist Nathalie Chèvre explains that there is no cause for concern regarding the residues of this product. She points out that the substance found in the affected mineral waters is not chlorothalonil per se, but degradation products «which are not known to be carcinogenic».

According to the Water Protection Ordinance, groundwater used as drinking water may not exceed the limit of 0.1 micrograms of pesticides per litre. However, the ecotoxicologist points out that this limit is no longer up to date. Ultimately, the limit value says nothing about the toxicological effects. It was set in the 1980s and 1990s because the 0.1 micrograms corresponded to the performance of the analytical tools of the time. In other words, it corresponded to what could be detected at the time. It is not a limit value motivated by health concerns.

The limit value has nothing to do with the risk of poisoning. According to the researcher, the standards are problematic because «a water can be above this standard without there being a health problem». The scientist also points out that it is not dangerous to drink bottled water or tap water in Switzerland. And she adds: «Before we look at the water, we should look at what's in our food or cosmetics».

When asked about the pesticide residues in mineral water, another expert reacts in a relaxed manner: «We are aware of these results and they correspond to the controls we carry out», Christian Richard, cantonal chemist for the canton of Vaud, comments to «24heures» and reminds us that Vaud's mineral water continues to comply with food law.