Frightening study

How glyphosate affects marine life

(Bild: stock.adobe.com/Pixavril, stock.adobe.com/Kolevski.V, Krone KREATIV)

Even the smallest amounts of pesticides irreparably damage important protozoa in the sea. Viennese researchers have discovered that an herbicide containing the active ingredient glyphosate has a particularly negative effect.

For the experiments at the Institute of Palaeontology at the University of Vienna, the scientists, who worked together with Polish colleagues, chose foraminifera - tiny, shell-bearing creatures that occur in coral reefs - as test objects. Foraminifera have been around for hundreds of millions of years. The single-celled organisms are usually found in the sea and react quickly to environmental changes, making them good bioindicators. Researchers have now investigated how pesticides affect the metabolic activity of a foraminifera species (Heterostegina depressa). 

Specifically, an herbicide, an insecticide and a fungicide were tested in different concentrations. "Even the lowest concentrations of herbicides or fungicides - we are talking about concentrations of 0.0001 percent, which can certainly be found in today's coral reefs - led to irreparable damage to the foraminifera," explained study leader Petra Heinz from the Institute of Paleontology at the University of Vienna in a press release.

The use of the controversial weedkiller glyphosate was extended for another ten years in the EU last year.(Bild: APA/AFP/Kenzo TRIBOUILLARD)

Glyphosate brought metabolic activity to a standstill
The "treatment" with glyphosate damaged the foraminifera after just one day to such an extent that metabolic activity was no longer detectable, according to lead author Michael Lintner, also from the University of Vienna, in the journal "Marine Pollution Bulletin". The fungicide also led to complete deactivation. According to the data, the insecticide had a significantly less negative effect on the foraminifera, or only at higher concentrations. 

Serious threat to marine reefs
Increasing storms and increased pesticide use due to intensive agriculture could lead to a significant increase in pesticide concentrations in the sea, the researchers fear. But even low concentrations would pose a serious threat to the health of marine reefs.