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
Swiss Politics
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.
Boats sail to Solothurn to celebrate 700 years of Le Landeron
This content was published on
The challenge of crossing Lake Biel from Le Landeron to Solothurn without a motor was taken up by 16 amateur crews on Saturday. The competition is part of Le Landeron's 700th anniversary celebrations.
Swiss cantonal ministers keep low profile on social media
This content was published on
A small base of followers and neutral posts: these are the conclusions that emerge from a study published by UNIL researchers into the use of social networks by councillors of state.
Swiss rents forecast to rise up to 5% annually, housing chief warns
This content was published on
Rents on the Swiss market are set to rise by between 3% and 5% a year over the next few years, warned Martin Tschirren, Director of the Federal Housing Office (FHO), on Sunday. "Demand for housing remains higher than supply".
This content was published on
The Council of the Swiss Abroad, meeting today in Bern, passed a resolution in favour of the new Electronic Identity Act (Id-e), which will be put to the vote on 28 September.
One person consumes 4.8 megawatt hours of electricity
This content was published on
On average, the Swiss consume 4.8 megawatt hours of electricity per year. According to Velobiz.de, this is roughly equivalent to the amount generated by all 176 cyclists in the Tour de France during the entire race.
Outgoing ICRC chief in Ukraine defends neutrality amid war
This content was published on
Swiss national Jürg Eglin, outgoing head of the International Committee of the Red Cross in Ukraine, reflects on his tenure.
Green party leader criticises government’s neo-liberal policy
This content was published on
The Green Party delegates' meeting opened on Saturday morning in Vicques (JU) with a speech by party president Lisa Mazzone. Mazzone took particular aim at the Federal Council's policy towards the United States.
Working on Sundays is detrimental to well-being, says Swiss study
This content was published on
A study by the University of Bern shows that working on Sundays is detrimental to well-being and particularly affects women.
Safra Sarasin private bank and former asset manager sentenced
This content was published on
The Office of the Attorney General of Switzerland has fined private bank J. Safra Sarasin CHF3.5 million for aggravated money laundering. A former bank employee received a six-month suspended prison sentence.
JPMorgan to pay CHF270 million to settle 1MDB claims
This content was published on
JPMorgan Chase has agreed to pay CHF270 million to the Malaysian government to settle all issues related to its role in the 1MDB financial scandal.
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.