Strong action is urgently needed to get farmers off the chemical treadmill.

Sandra Bell, Friends of the Earth's nature campaigner, said: 'From frogs to bees, there is mounting evidence that the pesticide bombardment of our farmland is having a major impact on our precious wildlife. He added that in the field, multiple sprays of a variety of pesticides was likely and that chemicals might run off into ponds where frogs lived. According to our knowledge, no significant impact on amphibian populations has been reported despite the widespread and global use of the fungicide pyraclostrobin.'īrühl said the method, a single spray directly on to the frogs, sometimes at just 10% of the label rate, was a 'realistic worst-case' scenario. Under normal agricultural conditions amphibians are not exposed to such pesticide concentrations. The study, published on Thursday in Scientific Reports, concluded: 'The observation of acute mortality in a vertebrate group caused by commercially available pesticides at recommended field rates is astonishing, since 50 years after the publication of Rachel Carson's Silent Spring one would have thought that the development of refined risk-assessment procedures would make such effects virtually impossible.'Ī BASF spokesman disputed the findings: 'This study was performed under laboratory 'worst-case' conditions. Other fungicides, herbicides and insecticides also showed acute toxicity, even when applied at just 10% of the label rate, with the insecticide dimethoate, for example, killing 40% of animals within a week. It killed all the common European frogs used as test animals within an hour when applied at the rate recommended on the label. The most striking results were for a fungicide called pyraclostrobin, sold as the product Headline by the manufacturer BASF and used on 90 different crops across the world. His team chose widely used fungicides, herbicides and insecticides. But pesticides are not required to be tested on amphibians, said Brühl: 'We could only find one study for one pesticide that was using an exposure likely to occur on farmland.' More than a third of all amphibians are included in the IUCN 'red list' of endangered species, with loss of habitat, climate change and disease posing the biggest threats.īrühl had previously studied how easily frogs can absorb pesticides through their permeable skins, which they can breathe through when underwater. Trenton Garner, an ecologist at the Zoological Society of London, said: 'This is a valuable addition to the substantial body of literature detailing how existing standards for the use of agricultural pesticides, herbicides and fertilisers are inadequate for the protection of biodiversity.'Īmphibians are the best example of the great extinction of species currently under way, as they are the most threatened and rapidly declining vertebrate group. That should translate into a dramatic effect on populations.' 'It is the simplest effect you can think of: you spray the amphibian with the pesticide and it is dead. 'You would not think products registered on the market would have such a toxic effect,' said Carsten Brühl, at the University of Koblenz-Landau in Germany.

Insecticides and pesticides orthro