Page 27 - Green knowledge 2022

Photo: Oskar Puschmann
Low concentrations of glyphosate in streams
Results from monitoring of the pesticide glyphosate in agricultural streams performed by NIBIO, show no basis to say that drainage from glyphosate to the surface water will result in negative environmental effects in Norway
Potential negative environmental consequences from widespread use of glyphosate have been a talking point in recent years. The EU is now assessing whether to phase out the pesticide.
A report from NIBIO highlights connections between environmental concentrations of glyphosate in areas’ agricultural streams and factors that affect the concentrations, such as weather conditions and operational and spraying practices. The study is focused on two agricultural catchments dominated by cereal production included in the national monitoring programme JOVA in the periods 1997–2000/2001 and 2016–2018. Glyphosate is used annually in these areas to control weeds.
“Through JOVA we now have over 25 years of monitoring data from the field. This means that we have the data which show the pesticide levels in agricultural streams over long periods,” explains Marianne Stenrød, Director of Division of Biotech- nology and Plant Health at NIBIO.
“The monitoring data for glyphosate show low concentrations in relation to the environmental toxicity of this substance, and we do not expect these levels to cause any negative environmental effects,” says Stenrød.
The main findings were that glyphosate persists longer in the Norwegian environment than previ- ously assumed, and that the substance has been detected in most water samples that have been analysed in agricultural areas where the agent is used regularly over larger areas. But these also showed that the concentrations are mainly low.
“The current practice therefore does not pose a hazard to the water environment,” concludes Stenrød.
Purpose: Understanding and knowledge of which factors affect detected concentrations of glyphosate in the water environment in order to provide recommendations for sustainable agricultural activity.
Contact: Director Marianne Stenrød. E-mail: marianne.stenrod@nibio.no, phone: +47 482 97 607. Division of Biotechnology and Plant Health
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