Persistence of pesticides threatens European soils

Two researchers from the scientific team of the European Diverfarming project at the University of Wageningen (Netherlands), Violette Geissen and Coen J. Ritsema, have analysed surface soil samples from 11 European countries, searching for traces of the pesticides used in the area of agriculture and they have confirmed the persistence of this type of product in the land.

After analysing 317 samples taken in 2015 from 11 European countries belonging to six different cropping systems, the study "Pesticide residues in European agricultural soils: a hidden reality unfolded" concluded that 83% of said samples contained pesticide residues (76 different types of compounds). Some 58% of that percentage were mixes of pesticides, as opposed to 25% which came from a single type of substance. Glyphosate, DDT (banned since the 1970s) and broad-spectrum fungicides were the main compounds detected.

Increased social concern regarding this issue has two basic precepts: the major persistence of pesticides in the soil (as shown by this study) and the toxicity for some non-objective species (those which are not targeted). Considering that the residues accumulate in the uppermost part of the soil, they will easily become airborne due to air currents.

To face up to this problem, the Diverfarming project financed by the H2020 programme of the European Commission, proposes a more rational use of the land and the inputs that are incorporated therein: water, energy, fertilisers, machinery and pesticides. A series of alternatives are proposed for preserving the soil microorganism balance and, therefore, the biodiversity and its very health. These range from the use of new non-persistent pesticides, bio-stimulants, organic composts or to ally with crop diversification which contributes to balanced insect communities and thus to the absence of pests.

According to the study, the presence of mixes of pesticide residues in the soil is more the rule than the exception, which illustrates the need to evaluate environmental risks in the case of these combined compounds to minimise their impact.

Those who are cultivating the land are becoming increasingly aware that in order to have good produce they need good soil, which means that studies such as that by Geissen and Ritsema, as well as strategies such as those proposed by Diverfarming are more and more essential in the European agriculture sector.

Diverfarming is a project financed by the Horizon 2020 Programme of the European Commission, within the challenge of "Food Security, Sustainable Agriculture and Forestry, Marine, Maritime and Inland Water Research and the Bioeconomy," which counts on the participation of the Universities of Cartagena and Córdoba (Spain), Tuscia (Italy), Exeter and Portsmouth (United Kingdom), Wageningen (Netherlands), Trier (Germany), Pecs (Hungary) and ETH Zurich (Switzerland), the research centres Consiglio per la ricerca in agricoltura e l'analisi dell'economia agraria (Italy), the Consejo Superior de Investigaciones Científicas (Spain) and the Natural Resources Institute LUKE (Finland), the agrarian organisation ASAJA, and the companies Casalasco and Barilla (Italy), Arento, Disfrimur Logística and Industrias David (Spain), Nieuw Bromo Van Tilburg and Ekoboerdeij de Lingehof (Netherlands), Weingut Dr. Frey (Germany), Nedel-Market KFT and Gere (Hungary) and Paavolan Kotijuustola and Polven Juustola (Finland)).