[Establishment and activities of scientific school of industrial toxicology in institute].

The article deals with stages of establishment and development of toxicologic studies in the Institute over 90 years. The authors stress the role of professor N.S. Pravdin and RAMSc Corresponding Member I.V. Sanotsky in formulation and solving major problems of toxicology, in specifying its methodologic background. Priority directions in theoretic and applied research are presented, main results are given.

[Hygienic standardization of biotechnological strains in water reservoirs: current state and perspectives].

The question of need for standardization and validation of the complex methods to establish the maximum concentration limit (MCL) ofbiotechnological strains in the water of water bodies is under discussion. On the basis of the experimental studies it has been shown that a unified quantitative criterion for safety could not to be recommended for biotechnological strains and therefore requires the study of each strain in order to substantiate the safe level in water of water bodies. Proposed biosafety program should include the study of pathogenic properties in acute experiments and specific effects in subchronic experiments to study the influence of strains on the process of water purification and a risk assessment of transformation products of chemicals and the justification of the safety factor when establishing MCL t in terms of the toxic effect.

[Scientific basis for hygienic classification of jeopardy caused by microorganisms applied in biotechnologies].

Based on studies of action characteristics (pathogeneity, general toxicity, immunotropic and dysbiotic effects) of 28 biotechnologic strains assigned to various taxonomy groups (Gram-negative and Gram-positive bacteria, nocardial actinobacteria and actinobacteria, mold fungi and yeast-like fungi) and literature data, the authors suggested hygienic classification of microorganisms according to their jeopardy effects in the body and adjusted this classification to recommendations of international organizations (WHO, OECD).

[Comparative studies of microbial strains used in biotechnology for the elaboration of biosafety standards].

Comparative studies of different microbial strains used in biotechnology as potentially hazardous for human health agents demonstrated their ability to cause adverse effects such as toxicity, immunotropic action, sensitization, and alteration of normal intestinal microflora in rats. It was shown that certain microscopic fungi of genera Aspergillus, Penicillum, and Candida as well as some gram-negative bacteria can affect the immune system and disturb the balance of microflora in rat intestines. Actinomycetes were found to produce minimal adverse effects. These observations can be used to elaborate hygienic safety standards for the work with industrial microorganisms and thereby reduce or minimize the risk of occupational infection and immune disorders.

[Problem in the hygienic regulation and standardization of biotechnological strains in reservoir water].

The pattern of the negative effect of biotechnological strains belonging to different taxons was experimentally studied. The effect of the strains manifested as imbalance of immunocompetent cells, development of immediate and delayed hypersensitivity, and altered qualitative and quantitative characteristics of the autochtonic microflora of the intestine. The minimum acting (10(5) cells/l) and non-acting (10(4) cells/l) enteral exposure levels were determined for the bulk of the test strains. Analysis of the authors' findings and the data available in the literature made it possible to propose a study program on the hygienic regulation and standardization of industrial microorganisms and their based microbiological products in the reservoir water.

[Problems and perspectives in the hygienic regulation of biotechnological strains of microorganisms].

The state-of-the-art of hygienic standardization of biotechnological strains of microorganisms is considered. The last century's investigations accumulated abundant experimental data on the estimation of the adverse effect of the strains, formulated main guidelines for evaluating the negative activity of producing strains, and proposed a schematic diagram for toxicological and hygienic investigations of new biotechnological strains. Further studies made it possible to elaborate their human hazard classification, to improve study programs, to substantiate a priority list, and to develop approaches to assessing the occupational microbiological risk.

[The immunotropic and allergenic activity of hydroxyapatite with an ultrahigh degree of dispersion]. / Izuchenie immunotropnoi i allergennoi aktivnosti gidroksiapatita ul'travysokoi dispersnosti.

Hydroxyapatite is a well-known biologic material intended for intraosseous implantation which is widely used in practical dentistry. The agent causes no inflammatory reaction at the site of administration and is not characterized by acute or chronic toxicity. The possibility of development of specific contraindications against hydroxyapatite has not yet been studied; such contraindications might be connected with its possible immunotropism and allergenic activity which are to this or that measure present in all materials used for implantation into the bone. Since hydroxyapatite is known as surfactant, we used in our studies its modification characterized by the highest specific surface known at present, and therefore the most biochemically active. "Cold", that is, not exposed to high-temperature treatment ceramics was used in order to prevent reduction of hydroxyapatite reaction capacity. Complex of animal experiments showed that hydroxyapatite cannot possess immunotropic or allergenic characteristics.