Pesticide use in agroecosystems: Consequences ¡

The discovery of pesticides provided man with new and powerful tools for his incessant fight against pests. Nowadays its use is recognized all over the world as an effective, relatively simple and fast method for its control. Usually, the active product of a pesticide is obtained by the chemical industry in a degree of purity ranging from 75 to 98%, the rest being manufacturing impurities. The technically pure product is not usually used directly in agriculture, hence the so-called formulations are used that contain the active matter more or less diluted in a solid support or liquid solvent, together with adjuvant substances that improve its action.

It is important to note that, from the toxicological point of view, these pesticide formulations include carrier substances, diluents such as water or organic solvents, additives and impurities, which may have toxic potential by themselves. It is for this reason, that the contamination of the environment by the chemical substances that are dragged out of the treatment areas, this situation has led to criticism regarding the use of pesticides and causes great concern when the effects that they bring with them are observed not only in the treated areas but in the untreated areas where long-term effects are manifested when more persistent chemical pesticides are used.

The contamination of water by pesticides occurs when they are washed away from crop fields to rivers and seas, causing the death of various forms of life necessary for the balance of some ecosystems. That is why they constitute a current problem, due to their stability in the environment, their concentration and transformation in living organisms. In areas of intensive agriculture, water is one of the resources that presents a high risk of contamination by pesticides because it is continuously exposed to the arrival of these substances. Medrano, Gutierrez and Ortega (2012), point out that waste is incorporated into aquifers and surface waters by being dissolved or suspended in the return waters used in irrigation.

Among the pesticides that are found as the main pollutant of rivers, lagoons, springs, surface waters and for human consumption, there are organophosphates, these are widely used in agriculture and although they degrade quickly in the environment, they are highly toxic, since they can affect human health causing permanent neurological damage. That is why the European Union legislation establishes a maximum of 0.1 µg/L of each of these pesticides for human consumption water without the total of them exceeding 0.5 µg/L.

Currently, there are few who doubt the benefits associated with the use of pesticides, in fact, the need for the use of pesticides to achieve continuity in the food supply, the maintenance of the quality of the same and sustainable production at a reasonable price, is a reality admitted by governments and international organizations, being the use of pesticides a universal practice and still in constant growth, especially in developing countries.

Once the pesticide is applied, the soil becomes the main reservoir of these substances, which can lead to a degradation of this natural component, considerably affecting the biology of the soil that is of great importance for the degradation of organic matter. Among the pesticides that can generate these effects are herbicides, fertilizer fungicides, among others. The presence of these substances in soils is produced by direct or indirect application in the different stages of evolution of a given crop.

Dear readers, in our geographical area that is purely rural with large expanses of agricultural areas, at some point statistics were published that indicated how in 2006, farmers in the southern area of the Lake used approximately five million kilograms of agro-toxic, part of which are discharged into rivers and waterways by rains and irrigation waters. Scientific research on environmental issues goes from the urgent to the extreme priority, since, in all the places on the planet where man has traveled, he has left a sequel of ruin and misery as a result of a productive, aggressive and decadent economic system that destroys the natural environment irreversibly.

This minimalist vision of man is decisive when pondering the current reality, which seeks to generate a new professional profile of the university graduate committed and dedicated to the unquestionable cause of helping the environment, since, the preparation of young people in this area is vital because of its transcendence, linking students from universities and technological in the cause of environmental quality constitutes one of the most important assets in the most harmonious development of humans with the environment. Unfortunately, human beings are currently considered the most dangerous environmental liability that the history of the planet has ever had, we must ask ourselves if we are making the right decisions to train future graduate professionals as men and women capable of facing the most urgent needs of the future.