The ban occurred amid an ongoing review of 100 substances, the agriculture office said.
New laboratory results had been provided by firms indicating the toxicity of certain chlorothalonil by-products.
The office said: “It is not possible to exclude that some chlorothalonil by-products do not have a long-term negative effect on health.”
The agriculture office supports the EU Commission’s assessment that chlorothalonil should be classified as a carcinogen. According to the World Health Organisation (WHO), chlorothalonil is especially toxic to fish and aquatic invertebrates. Exposure to the agent can cause kidney and stomach damage, including tumours, in rodents. A ban on the substance will take effect in the European Union in 2020, following conclusions from the European Food Safety Authority that the agent could pose a health risk.
Drinking water risk
Swiss officials said it was important to “act quickly” to reduce the presence of chlorothalonil by-products in groundwater, as they may exist at levels above legal standards set for drinking water in Switzerland.
Last June drinking water in a village in canton Fribourg had to be cut after excessive amounts of chlorothalonil were discovered.
The Swiss authorities say the requirements for approval of plant protection products have been tightened in recent years. They say products that were eligible for approval 20 years ago are not necessarily the same today. The pesticide approval process in Switzerland is currently being reviewed by an external audit firm.
The government is taking measures against contaminated drinking water with its action plan to reduce pesticide pollution and the Agricultural Policy 22+, but critics say these do not go far enough. Two popular initiatives on drinking water are pending. Although the government has rejected these, voters are likely to have the final say next year.
More
More
Pesticide companies ‘seriously deficient’ on human rights, says UN toxics expert
This content was published on
The UN Special Rapporteur on Toxics believes pesticide companies and the Swiss government should do more to phase out hazardous chemicals.
Should raw milk sales be banned or should consumers decide?
Swiss food regulations do not allow raw milk to be sold for direct consumption. However, a loophole allows 400 raw milk vending machines to do just that.
COP29: Swiss NGOs call for strong financial support
This content was published on
Ahead of COP29, Swiss NGOs call for wealthy nations to pay $1,000 billion a year to help other countries solve climate problems.
Real Swiss wages likely to rise in 2025, says UBS bank
This content was published on
Higher wages and falling inflation are likely to boost Swiss purchasing power, which will be dragged back by rising health premiums.
This content was published on
Switzerland has a new tectonic map at a scale of 1:500,000, containing updates to geometry, distribution and nomenclature of the tectonic units.
This content was published on
Swiss artist Daniel Spoerri, known for his artworks using leftover food with dirty cutlery and crockery, has passed away in Vienna at the age of 94.
Climate change tipped to alter Swiss avalanche patterns by 2100
This content was published on
Climate change is expected to result in fewer avalanches overall in Switzerland but to increase the danger of wet snow avalanches by 2100.
Pesticide companies ‘seriously deficient’ on human rights, says UN toxics expert
This content was published on
The UN Special Rapporteur on Toxics believes pesticide companies and the Swiss government should do more to phase out hazardous chemicals.
This content was published on
Swiss pesticide approval procedures are still far from transparent, fueling strong suspicions of collusion between the authorities and industry.
Pesticide residues found on 93% of organic Swiss farms
This content was published on
Most fields on organic farms in Switzerland are contaminated with pesticides, according to a study by the University of Neuchâtel.
This content was published on
A UN representative is demanding action following reports that Swiss crop science company Syngenta is selling highly hazardous pesticides abroad.
You can find an overview of ongoing debates with our journalists here . Please join us!
If you want to start a conversation about a topic raised in this article or want to report factual errors, email us at english@swissinfo.ch.