Urgency of Hygienic Rating of Pesticides in the Soil

Abstract

The requirement concerning the implementation of the research in the extreme soil-climatic conditions promoting the maximum migration in environments contacting to the soil (water, air, plants), and also providing most their intensive impact on processes of self-cleaning and a soil microbiocenosis is one of the basic provisions of the theory of hygienic rating of active ingredients of pesticides in the soil. For the creation of extreme conditions, the experiment is carried out on the sandy soil possessing the maximum filtering, minimal sorbing and absorbing ability. The observance of a principle of extremeness is provided with executing the research at microclimatic parameters (temperature, humidity, ultraviolet radiation), pesticides promoting the maximum migration on contacting media and the use in the experiment of plants concentrators creating a considerable margin of the safety in hygienic rating. All investigations are carried out in the standard and comparable soil and microclimatic conditions with the use of the uniform simulating standard modeling soil standard based on the constant granulometric and physical-chemical structure of the sandy soil and uniform microclimatic parameters. By analogy to a rating of active ingredients of pesticides in water of reservoirs, atmospheric air, etc., studies are carried out not in natural surroundings, but only in uniform comparable with experimental conditions on laboratory modeling installations. On the basis of the established threshold concentration on migratory water, migratory air, translocation and all-sanitary indices of harm there is chosen the limiting one, on which maximum concentration level is established. Established maximum concentration limits of active ingredients of pesticides in the soil are the uniform in size for any soil-climatic conditions. On the established uniform maximum concentration limit of active ingredient of pesticide in the soil if necessary it can be determined the regional maximum concentration limit for conditions of the concrete soil and climatic region. In the calculation of this size, there are considered leading factors: temperature, humidity of the soil, maintenance of a hummus, рН, porosity, bacterial load, etc. The factors characterizing the influence of these factors on processes of migration and a detoxication of active ingredients of pesticides were found on the basis of the research have been carried out on natural samples of the soil of this region.