[Model of the assessment of the risk of conditions of the work with the use of pesticides: results and development].

There is implemented the development of the model of assessment of the risk from working conditions/ This model allows to solve the problem of the safe use of pesticides in agricultural production of the Russian Federation. The importance of the parallel assessment of the risk for the specific factor of the external exposure to operators (SF ex.) and absorbed dose (SF int.) is presented. Studies of more than 500 pesticides have shown the following correlation of the SF ex. and SF int.: in 8.3-37.5% cases SF ex. and SF int. were practically equal, in 44.8-85.7% cases SF ex. was higher up to by 10 times and in 8.3-26.3% cases SF int. is higher up to by 30 times. Introduction of the new evaluation criterion SF int. increases reliability of the risk assessment.

[Hygienic regulation of neonicotinoids derivative in the soil].

For the assurance of the safe regulations for the use in agriculture persistent in soil insecticide neonicotinoids derivative, studies have been executed to investigate its impact on the soil microbiocenosis and migration to the neighboring environment of the active ingredient of this pesticide and the preparation based on it. On the ground of obtained experimental data there were determined threshold doses for the following indices of the harmfulness: migration-water, translocation (transmission into plants) and general sanitary indices. There were established limiting indices of the harmfulness: translocation and migration-water indices. The maximum permissible concentration (MPC) of neonicotinoids derivative in the soil accounted for 0.5 mg/kg of the soil. This content of the pesticide in the soil prevents its accumulation in plants in concentrations exceeding the maximum permissible levels (MPLs), in food products, it fails both to give rise in its transition in groundwater above the MPL for water reservoirs and influence on the soil microbiocenosis and self-purification processes.

[The improvement of methodical approaches of hygienic regulation of pesticides in water bodies].

The article highlights the methodical features of hygienic regulation of pesticide preparation in water bodies, concretizes and supplements (specified) number of positions of the acting current methodical document on hygienic evaluation of new pesticides. From the position of the comprehensive hygienic standardization there are marked principles of the study of MPC for pesticides in water bodies, there is substantiated the expediency of expanding the arsenal of methods for determination of threshold concentrations of pesticides on the impact on organoleptic properties of water and sanitary regime of reservoirs, shows the role and importance of hydrolysis processes of active ingredients ofpesticides in water, which should be considered in the assessment of the impact of drugs on the processes of self-purification of water bodies.

Nongenotoxic (epigenetic) carcinogens: pesticides as an example. A critical review.

The following groups of pesticides are considered in this review by supposed mechanisms of their carcinogenicity: hepatocarcinogenic pesticides, pesticides - peroxisome proliferators, pesticides as endocrine disruptors, goitrogenic pesticides, pesticides producing sustained cell proliferation and some others. With very rare exceptions, pesticides do not react with DNA directly and the mechanisms of their carcinogenicity are, in general, similar to those of other nongenotoxic (epigenetic) carcinogens, namely: promotion of spontaneous initiation, cytotoxicity with sustained cell proliferation, oxidative stress, formation of activated receptors and some others. Genotoxicity of pesticides varies from its complete absence (propiconazol as an example) to a very pronounced one (captafol) with remaining compounds in between. These two compounds demonstrate full correlation between genotoxicity and carcinogenicity (or their absence). Many pesticides give positive results in some tests for genotoxicity but these results are frequently controversial, not readily reproducible, or obtained only at toxic dose levels. The weak genotoxicity of the majority of pesticides is easily explainable by their rather severe testing before their introduction into practical use. The above mechanisms are threshold-based and therefore pesticides are regulated through NOEL/safety factor. There exist examples of lack of correlation between genotoxicity and carcinogenicity: some pesticides are genotoxic (although not strongly) but noncarcinogenic, others are considered as nongenotoxic but are strongly carcinogenic (chlorothalonil, acetochlor). The general scheme of the promoters' effect is presented in which an important role is attributed to the cytochrome P-450 induction (some pesticides are the cytochrome P-450 inducers), formation of reactive oxygen species and peroxitome proliferation. Teratogenesis Carcinog. Mutagen. 20:229-240, 2000.

Hygienic classification of pesticides in the Russian Federation.

Hygienic classifications of pesticides used in the Russian Federation are presented. The classifications cover both technical products and preparative forms of pesticides. Four classes of hazards are distinguished: extremely hazardous, hazardous, moderately hazardous, and slightly hazardous. These four classes are used for classifying general toxicity (peroral, skin, inhalation), cumulative, allergic, teratogenic, embryotoxic, reproductive, mutagenic, carcinogenic effects, and the stability in soil. The class of the hazard is determined on the basis of toxicohygienic evaluation of a pesticide, taking into account a limiting criterion of the hazard.