Gesundheitstipp analyzed 30 popular beers in Switzerland from both large and small breweries and found that 12 of them contained residues of glyphosate, the active ingredient in the widely-used weedkiller Monsanto, often used on crops including barley and wheat.
Topping the list was Coop Prix Garantie lager, containing 21 micrograms per litre of glyphosate, far more than the second highest, Guinness draught, which contained 13 micrograms.
Oettinger Export, Calanda (brewed by Heineken), and Einsiedler lager from the Rosengarten brewery in the canton of Schywz all contained traces of the pesticide, as did La Salamandre from popular Jura microbrewery BFM and even an organic beer from the Graubünden brewery Bieraia Tschlin.
Reacting to the study Coop said its beer was brewed in Germany and that the Swiss government considered these “traces” to be harmless, said Swiss daily Blick.
Supermarkets Aldi and Lidl, whose beers were also highlighted by the study, said they would take the issue seriously and “respond immediately to new insights” according to Blick.
The Gesundheitstipp study followed a similar analysis of German beers by the Environmental Institute in Munich which found that the country's 14 most popular beers all contained traces of the pesticide.
All 14 exceeded Germany's legal limit for glyphosate in drinking water, of 0.1 micrograms per litre.
Glyphosate is the most used pesticide by farmers in Switzerland and is approved by the Swiss federal office of agriculture.
However in March last year the WHO's cancer agency published a report saying the pesticide was “probably carcinogenic to humans”.
Following the report Coop – along with a second Swiss supermarket chain, Migros – removed Monsanto from its shelves.
But the Swiss government refused to ban the sale of products containing glyphosate, saying in a statement in July that the latest studies into the pesticide found no evidence of it being carcinogenic.
Based on current data the Swiss federal health office (BAG) “considers that traces of glyphosate coming from the use of this product as a weedkiller are harmless to the public”, said the statement.
The WHO cancer agency had no new international studies available upon which to base its reclassification of glyphosate, it said.
In September Swiss broadcaster RTS reported that glyphosate was found in the urine of 40 percent of participants in a study carried out in French-speaking Switzerland.
Toxicologist Vincent Perret told the broadcaster at the time that gylphosate doesn't stay long in the body, so finding it in 40 percent of those tested means “that population is fed glyphosate in a chronic, permanent manner”.
Reacting to that study, BAG said the amount of glyphosate found in the urine was “very small and harmless to health”.
In Switzerland glyphosate is mostly used to promote the fertility of the soil, according to BAG.
“The use of glyphosate just before the harvest, as used by other countries to speed up the maturity of crops, is not authorized in Switzerland,” it added.