Glyphosate safety profile for non-target wildlife and plants
When herbicides are sprayed on fields, wildlife and plants other than weeds are also likely to come into contact with them. Therefore a number of studies are prescribed by the authorities to ensure that substances do not pose any unacceptable risks to non-target plants and animals. The required studies are conducted with representative species of various forms of wildlife, including insects, earthworms, birds and mammals.
Science-based evaluations conducted by regulatory bodies and other scientific institutions have concluded that typical glyphosate usage does not pose any unreasonable risks to wildlife when used according to label directions. Glyphosate is readily degraded by soil microbes to aminomethylphosphonic acid (AMPA) and carbon dioxide and, therefore, generally dissipates rapidly from agricultural environments as well as from more complex ecosystems such as forests and wetlands. In addition, glyphosate adsorbs strongly in the soil which limits its ability to run off fields and enter water bodies and limits the exposure of any organisms outside the site of application 4,5,7.
In all the organisms tested, including earthworms, birds, mammals and arthropods, glyphosate exhibited only low toxicity at typical application rates. Honeybees were not affected by a glyphosate based-formulation even when they were fed high concentrations or exposed in semi-field studies when gegetation adjacent to beehives over-sprayed 2. These results are also supported by a recently completed bee brood study conducted to meet current EU testing requirements for the ongoing glyphosate renewal process.
Moreover, potential risks for most aquatic organisms are mild or negligible if glyphosate is used according to label instructions, and fish, frogs and aquatic invertebrates are not affected by typical glyphosate usage. Since glyphosate does not bioaccumulate in fish or other animals it is not expected to have long-term impacts on the ecological food chain.
Together these results have led to glyphosate being considered as a comparatively benign herbicide compared to most alternative products for chemical weed control.
Because of this relatively favourable safety profile, glyphosate products have even been used in protected habitats such as the Galapagos Islands and the Florida Everglades to protect the native flora from invasive weed species 1,6.
- Study: Glyphosate and AMPA chronic risk assessment for soil biota (2016)
- Glyphosate safety profile for human health
- Environmental fate and behaviour of glyphosate
Last update: 11 April 2016