[Late changes in the body function of the inhabitants in the area of the eastern Urals radioactive trace]. / O nekotorykh otdalennykh izmeneniiakh sostoianiia organizma zhitelei v zone Vostochno-Ural'skogo radioaktivnogo sleda.

Using a mathematical methodology based upon the theory of pattern recognition, the adequacy of this methodology being confirmed by the corroborative results obtained with neuro-net non-parametric methods of analysis, it proved possible to discriminate reliably between generalized organism's statuses, as described with a big number of laboratory indices, of the inhabitants of different areas of a big industrial city which differ in levels of radioactive and non-radioactive environmental pollution.

[Percutaneous effects of iodine inhibit the development of experimental silicosis]. / Tormoziashchee deistvie ioda na razvitie éksperimental'nogo silikoza pri perkutannom vozdeistvii.

Experiments on white rats proved that the silicotic pulmonary changes slowed with the tails periodically immersed into iodine solution. Those pulmonary changes were due to inhalation of quartzite dust and especially due to intratracheal administration of standardized quartz dust DQ12. Influenced by inhalation of dust containing quartz, the rats demonstrated characteristic alterations in cytologic features of bronchial and alveolar lavage water. The "iodine baths" also declined those alterations, that may prove higher resistance of pulmonary macrophages to cytotoxic effects of quartz. This hypothesis finds a support in experiments with culture of rat peritoneal macrophages. If incubated in a medium with low iodine concentrations and subsequently washed off, the macrophages demonstrate lower incidence of cytotoxic effects due to the next incubation with particles of DQ12. The macrophage's higher resistance against cytotoxic agents is believed to result directly in antisilicotic effect of iodine, so "iodine baths" could be recommended for pathogenetic therapy and medical prophylaxis of silicosis.

On the relationship between activation and breakdown of macrophages in the pathogenesis of silicosis (an overview).

Silica particles cause considerable damage to macrophages resulting in their eventual breakdown. At the same time, the development of silicosis involves a number of mechanisms associated with the activation of macrophages. In suggesting schemes for the pathogenesis of this disease many authors associate the central part with activation, completely neglecting damage to cells. Our experiments have shown, however, that much of the activation phenomena could be reproduced in vitro or in vivo by exposing macrophages to macrophage breakdown products. Alternatively, the secondary character of activation is demonstrated by the fact that it reveals itself only at silica doses which cause part of the cells to lose their viability in the same culture. Our data show that the range of macrophage activation phenomena which could be considered as secondary with respect to the breakdown of cells includes the production of neutrophil attractants, enhanced co-operation with T lymphocytes, increase in phagocytic activity, enhancement of cellular O2 consumption and peroxidation, an increase in the activity of dehydrogenases, reduction in the activity of 5'-nucleotidase, and some other effects. Although not denying that small silica doses may be able to exert a direct activating influence upon the macrophage we do, however, believe that the most important and primary role in the pathogenesis of silicosis is played by the damage to and the breakdown of this cell.

[Effects of antioxidant state on individual susceptibility to silicosis (an experimental study)]. / Vliianie antioksidantnogo statusa organizma na individual'nuiu predraspolozhennost' k silikozu (éksperimental'noe issledovanie).

The authors proved that animals having higher natural antioxidant activity and lower intensity of lipid peroxidation are more resistant to fibrogenic effects of quartz. The peritoneal macrophages obtained from those animals show higher resistance to quartz exposure "in vitro". Parameters characterizing antioxidant system should be included into a group of indexes describing propensity to silicosis.

[Experimental study on risk factors of pneumoconiosis caused by dust in the industry of new construction materials containing glass and coal waste]. / Eksperimentalnoe izuchenie pnevmokoniozoopasnosti pylevogo faktora v proizvodstve novogo tipa stroitelnykh materialov iz stekla i ugolnogo shlaka.

The study compared cytotoxicity and fibrogenic ability of quartzitic dust to that appearing at 3 sites of light building filler production based on ground glass or clinker. Obtained results prove possible pneumoconiosis development caused by exposure to such dust types, especially in the production using ground glass. The MAC in this type of production is 2 mg/cu m, for the dust in production using clinker the MAC is 4 mg/cu m.

[Significance of short-term cytotoxicity tests for hygienic assessment of industrial aerosols]. / O znachenii sistemhy kratkovremennykh testov na tsitotoksichnost dlia gigienicheskoi kharakteristiki promyshlennykh aérozolei.

The evaluation of low-soluble particles toxicity for human phagocytes (primarily, for macrophages) was proved to have advantages in predicting their effects on the human body and in rapid toxico-hygienic regulation. The preference is given to tests "in vitro". If comparative toxicities of substances in group are discordant according to different "in vitro" tests the decision must be made after the "in vivo" evaluation of cytotoxicity: in 24 hours after the intratracheal administration of small doses of these low-soluble particles the bronchoalveolar lavage is examined cytologically. Reliable neutrophilia in lavage is of great value.

[Hygienic regulation of dust of magnesium-silicate minerals and fireproof materials]. / O gruppovoi gigienicheskoi reglamentatsii pyli magnezialno-silikatnykh mineralov i ogneupornykh materialov iz nikh.

Chronic experiments on rats showed that the dust of silicomagnesian refractory and dunite (a raw material for refractory production) extracted in Kytlym differ insignificantly in fibrogenic activity, but rank below the quartzite extracted in Pervouralsk (MAC-1 mg/cu m). The short study analyzing the cytologic changes of bronchoalveolar lavage determined the cytotoxicity of silicomagnesian refractory and 4 other types of dunite. The estimated cytotoxicity also ranked below that of quartzite from Pervouralsk. The MAC equal to 4 mg/cu m was suggested for the group of aerosols produced by dunite and silicomagnesian refractories. These aerosols are assigned to the 3rd jeopardy class and possess basically fibrogenic activity.

Trends and perspectives of the biological prophylaxis of silicosis.

Based on earlier paper in this journal, as well as on new data concerning factors predetermining individual susceptibility to silicosis, we propose a comprehensive system of recommendations aimed at increasing the working population's resistance against the harmful action of silica dust. These recommendations consider, on one hand, the criteria of possible selection for employment in dusty industries of individuals who do not possess characteristics making them especially sensitive to this harmful action (collective biological prophylaxis), and on the other hand, the influences that could diminish such sensitivity (individual biological prophylaxis). Some ethical and practical problems of the biological prophylaxis of occupational diseases and a mathematical approach to predicting its effectiveness are also discussed.