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The contributors used the sensibilization threshold to establish MACs for the dust of the fodder yeast produced as a result of pulp and paper waste products' recycling. The product belongs to the group of substances with low toxicity. It does not produce local irritation and exhibits sensibilization properties in case of both epi- and intracutaneous introduction. The sensibilization threshold in repeated introductions of protein-containing dusts was registered at 4.1 mg/m3. In industrial conditions, the fodder yeast concentrations at the level of about 4 mg/m3 caused increased morbidity with temporary disability.

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The paper presents the results of a study of the qualitative composition and quantity of pollutants in atmospheric air in the course of operational wear of the road surface, braking system and tire treads of automobiles. On the basis of field research in samples ofatmospheric air ofthe city of St. Petersburg there were identified compounds of heavy metals andpolycyclic aromatic hydrocarbons (PAHs). There was established the dependence of the level of air pollution on traffic flows in locations of the city. Pollutants were shown to enter the air environment mainly in the form offine dust particles. There was justified the need for the control ofproducts of wear the road traffic complex in the hygienic assessment of the quality of ambient air ofmegalopises.

The paper reviews literature on the current aspects of the diagnosis and expert appraisal of focal osteoplastic masses in the lung upon dust exposure to dust factors. It considers different aspects of the pathogenesis of osteoplastic changes in the tissue structural elements of pulmonary histione. Current views on the prevalence, etiology, and pathogenesis, as well as morphological changes in the development of this abnormality, its association with the dust damaging effects of human activities are reflected.

The paper gives data on the prevalence and pattern of chronic bronchopulmonary diseases (CBPD) in 188 workers engaged in carbonyl production of nickel versus 162 auxiliary process workers. Chronic bronchitis was the most common disease in both groups (11.2 and 5.6%, respectively). 9.6% of the carbonyl production workers were found to have toxic pneumofibrosis developing mainly in those having a service length of more than 20 years. As compared with auxiliary process workers, the nickel production process workers had a higher risk of CBPD (odds ratio 1.80; 95% confidence interval 1.00-3.22; p = 0.04496) who also came to the front in the pattern of occupational diseases (73.2% of all cases).

The paper analyzes an association between occupational risk factors in the female workers of greenhouses and allergic diseases in their children. The major factors contributing to the occurrence of allergic disease in children are their maternal employment in greenhouses with harmful working conditions, much dust in an apartment, a family history of allergic diseases, and unfavorable family lifestyle.

The authors consider the organization of a system for monitoring of ambient air pollution by suspended matter (by fractions of less than 10 microm and less than 2.5 microm) as one of the most urgent tasks in the harmonization of the Russian and western methods for assessing the quality of the environment. The frame plan for organization of ambient air suspended matter monitoring in the countries of Eastern Europe, Caucasia, and Central Asia, proposed by the WHO European Regional Office provides basic guidelines for this system and may be adapted to Russian conditions, as evidenced by the author's experience. The paper summarizes the basic results of the studies that have established the association of respiratory disease in junior schoolchildren with exposure to PM10 and PM2.5.

The urgency of the discussed issue is caused by the need to provide the technology of industrial recycling of technogenic dust in air of mining enterprises. The main aim of the study is to develop the technique for calculating the efficiency of the existing dedusting systems - centrifugal inertia with air exhaust louver, wet and magnetic ones. The methods used in the study: system approach with analytic calculations, methods of experiment measurements and investigations of dedusting systems. The results: The paper introduces the technique for calculating the efficiency of the developed dedusting systems: centrifugal inertia with air exhaust louver, wet and magnetic ones. To ensure regulatory residual dust concentration in emissions taking into account the reliability of dust collectors in their operation the authors have estimated the efficiency of the systems under conditions differing from the experimental ones. The paper describes the technique, design and operation principle of new devices for analyzing dust particulate materials. The article considers the concept of integrated models and constructions of certain devices and systems to analyze dust particulate materials. The concept combines new and existing complementary methods, and means of analysis of dust particulate materials. The work is devoted to investigation of estimation problem for different logical models and mode of operation of new devices for the analysis of dust particulate materials. Application of the devices proposed can significantly reduce duration of analysis in comparison with the known methods: in one device the separation of the particle size is done by sedimentometer, in another device - by particle motion rate in the air. The paper considers the concept of integrated ecology problems which combines complementary methods and devices for the analysis of dust particulate materials and powders disperse composition. The authors propose the methodology for calculating the efficiency of the developed dedusting systems: the centrifugal inertia with air exhaust louver, wet and magnetic ones. It is shown that the account of equations of parameters connections in new devices applying a new analyzing technique for powder and dedusting materialsparticle distribution determines the difference from zero of estimations approximations. It allows solving the estimation problem of particle sizes, fractions, control and diagnosis out-of-frame of traditional approaches to the problem solution.

The paper deals with the use of a laser flow-type fluorescence aerosol particle counter to evaluate the concentrations of microbes in the surface air under high dust content. Various circuits of flow-type optic aerosol recorders are analyzed. Flow spectral luminescence analysis of some particles flow while exciting the fourth harmonics of a pulse laser on yttrium-aluminium garnet with neodymium by ultraviolet radiation is shown to be the most optimum method for indication of individual aerosol particles. Experiments were conducted on the authors' model of a pilot plant based on this method. The model of a laser flow-type optic analyzer was developed for experimental studies that give a clear display of biological aerosols in complex aerosols. The laser flow-type analyzer-based unit developed may provide a fluorescence signal of aerosol particles in the flow of a sample and that light diffusion signal from them at an exciting light wavelength of 266 nm. Experiments with BVC aerosols and soil dust particles were conducted in different regions of Russia. They showed it possible to detect and to rapidly calculate soil microorganisms by laser flow-type fluorescence assay of individual particles when excited by ultraviolet radiation.

Sensibilization activity of the fodder yeasts grown on the sulphate wastes of pulp and paper mills in inhalation, into and onto skin injection experiments with guinea pigs was studied. This activity depended on the action intensity. Application onto skin is more effective, than injection into skin. 10 mg/m3 caused statistically significant allergic effects in inhalation experiments, but 0.8 mg/m3--had no significant effects.

The paper deals with the problem of dependency of the reduction of microbial contamination and of dust pollution of the air mediu min the CAMERA-BOXES with a liminary flux on the aeration degree. It was shown that the degree of aeration in the camera-box constituted from 330 to 1060, with the rate of the air flux at the filter exit of from 0.2 to 0.6 m/sec. Vertical laminar flux provided release of the air from the microbes and dust. The use of the camera-box with a laminar flux for work requiring sterile conditions is recommended.

Paper is the second part of the literature review on house dust mites (including 1985). It deals with the diagnosis of the dust mite allergy, the nature of the mite allergens, distribution and population density of the mites in various premises, seasonal population dynamics and population age structure of the dermatophagoid mites, life cycle and breeding of Dermatophagoides pteronyssinus and D. farinae on different food substrates. The methods of the house dust mite control are discussed. The original data on the house dust mite distribution in Moscow is shown. A comparative estimation of the results of mite antigens in the house dust discovering by the acarological and three immunological methods are given.

Dustiness of the mine atmosphere during carrying out exploitation is one of the most hazardous factors threaten to health and life of employees. Also it is large hazard for all type of mechanical and electrical devices operating in mining headings. Coal dust is also very dangerous due to its possibility of explosion. Currently applied technologies of rock mass mining process, entire transport process of output and applied ventilation system cause that rock and coal dust is presented practically in each of the mining heading. Practically, is impossible to eliminate dust from mining headings. However, one can determine its parameters and potential ways its displacement. In the paper there is presented modeling research methodology of dustiness state in a driven dog heading. Developed model is the basis for this methodology, including the diphase flow of mixture of air and dust in the mining heading. Analysis was performed for real driven dog heading. Based on performed analyses, distributions of particular fraction and movement trajectories of selected dust grains were determined. Developed methodology gives a lot of opportunities for analysis of dustiness state in mining headings and in other compartments. It enables to determine parameters of particular grains and their impact on ventilation parameters of the air stream in the tested headings. Obtained results can also be used to reduce dust hazard.

Introduction. The paper considers the mathematical analysis of the fractional composition of dust generated during the operation of the rail-cutting machine. It is established that the studied polydisperse material is well described by the one-parameter exponential distribution. At the same time, the lognormal particle size distribution, whose parameters are determined by mathematical programming methods, seems adequate for the purposes of calculating cyclones. The work objective was to develop mathematical methods for correct averaging of the size and mass parameters of dust under the solid metal machining.Materials and Methods. We studied the possibility of approximating experimental data by Rosin – Rammler distributions (classical, generalized three-parameter P(x, D, n, m), and simplified exponential P(x), in which n = 1). The corresponding results were compared to each other and to the data of approximation of the lognormal and double lognormal functions. These results indicate close approximation quality using the following model distributions P(x):• five-parameter double lognormal;• three-parameter type of Rosin-Rammler;• two-parameter classical Rosin - Rammler;• one-parameter exponential.Results. The primary physical analysis of cutting waste was carried out by the laboratory measuring complex Fritsch Analysette 22 Compact which uses the LALLS – low angle laser scattering method. The built-in software provides output of measurement results in primary graphic and digital forms. It was found that the simplest exponential distribution is best suited for a detailed analysis of the dust particle-size distribution based on the experimental data.This distribution enables reproduction of all the integral indicators provided by the instrumental measuring complex along with the graphical data.Discussion and Conclusions. The results obtained can be used to rationalize the local suction machine, and the mathematical models and algorithms can be used for the parametric analysis of any dust captured by cyclones.