Levels of glyphosate in vineyard soils and potential adverse effects to the environment

Abstract: Glyphosate is a broad-spectrum herbicide and is the most used worldwide, accounting for around 25 % of the global herbicide market. Recently, the use of this herbicide become one of the hottest debates between scientific community as well as national/international authorities. The European Food Safety Authority (EFSA) classified glyphosate as safe, however there are several studies that suggest it is toxic to aquatic and terrestrial organisms. Thus, this work intends to contribute to the knowledge about the behaviour and toxicity of glyphosate in the environment. For this purpose, the potential adverse effects of glyphosate to aquatic and terrestrial organisms were evaluated using an artificial soil contaminated with different concentrations of glyphosate. In parallel, the levels of this herbicide were monitored in two different vineyards from the Douro Demarcated Region (Portugal) over one year. Preliminary results showed that, the highest concentrations of glyphosate were, as expected, observed during the application period (in February) for both vineyards, and levels decreased in the following months. According to the results of ecotoxicological assays, it is not expected that levels of Glyphosate found in vineyard soils will pose a risk to both terrestrial and aquatic organisms.