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Methods of intensifying the anaerobic microbial decomposition of the organic fraction of municipal solid waste (MSW) on an MSW landfill and in anaerobic reactors were studied. It was discovered that it is preferable for the initiation and stabilization of the process of anaerobic digestion of organic waste in laboratory bioreactors at 20 and 50 degrees C to use a mixture of activated suspension of soil from the anaerobic zone of the landfill and digested sewage sludge. Stimulation of methanogenesis was shown in field conditions when digested sewage sludge was added directly into the upper layer of anaerobic zone of the landfill. The investigation of methane production during fermentation of concentrated food waste with a mixture of excessive activated sludge in the laboratory under thermophilic conditions (50 degrees C) has shown that the main problem at the first stage of the process was the acidification of the digested mixture due to the accumulation of volatile fatty acids. It was shown that for stable operation of the bioreactor under thermophilic conditions the amount of inoculum added during the start up should be no less than 30%-50%--based on volatile suspended solids. A sharp decrease in the digestion temperature from 50 to 20 degrees C did not cause methanogenesis termination, since the thermophilically fermented biomass contained both thermophilic and mesophilic methanogens.

Several active microbial communities that form biogas via decomposition of cellulose and domestic food waste were identified among 24 samples isolated from different natural and anthropogenic sources. The methane yield was 90-260 ml CH4/g from microbial communities grown on cellulose substrates, office paper, and cardboard at 37 degrees C without preprocessing. Under mesophilic conditions, bioconversion of paper waste yields biogas with a methane content from 47 to 63%; however, the rate of biogas production was 1.5-2.0 times lower than under thermophilic conditions. When microbial communities were grown on DFW under thermophilic conditions, the most stable and effective of them produced 230-353 ml CH4/g, and the methane content in biogas was 54-58%. These results demonstrated the significance of our studies for the development of a technology for the biotransformation of paper waste into biogas and for the need of selection of microbial communities to improve the efficiency of the process.

A screening study was performed to identify factors of the raised risk of cardiovascular and bronchopulmonary diseases among workers involved in weapons and military technology recycling and disposal. A high prevalence of risk factors such as smoking, excess body mass, adiposis, disorders of the carbohydrate, lipid and purine metabolism was found for workers aged 35 years and older. Circulatory, musculoskeletal, and eye diseases prevailed in the structure of first diagnosed diseases. Taking into account an unfavorable profile of risk factors, groups with the raised risk of cardiovascular and bronchopulmonary diseases were identified. An expansion of the standard scope of examination in the framework of regular medical monitoring in compliance with the applicable regulatory documents by inclusion of screening studies would provide additional opportunities for the early diagnosing and prevention of the above diseases.

According to the national plan of actions on environmental protection, industrial garbage recycling is to be introduced in Almaty and Astana for the sustainable development of the Republic of Kazakhstan. Integrated assessment of the hazard of garage is made by the sanitary-and-chemical and sanitary-and-epidemiological indices to provide the hygienic and ecological reliability of a procedure for neutralization and utilization of solid garbage (SG). According to the data obtained, Astana SG Astana in summer is characterized by the high total level of bacterial contamination. The indices of microbial contamination of SG and soil near the dustbins correlate with the density of population and the maturity of an infrastructure. Comparison of the sanitary-and-epidemiological indices of different types of SG (wastes from housing facilities, wholesale and retail outlays, and education, culture, and entertainment institutions) revealed no significant differences. According to the sanitary-and-helmintological indices, the Astana soil should be classified as pure (noninvasive). Involvement of SG into industrial recycling should be accompanied by a hygienic assessment of the hazard of waste and the reliability of used technologies in the context of warning and on-going sanitary surveillance.

Methane oxidation in the cover soil of the Khmet'evo municipal landfill in Moscow oblast was investigated. Methane emission from the experimental parcel of the site was highly inhomogeneous. At a depth of 45-60 cm, the pore gas mainly consisted of CH4 (60-70%) and CO2 (30-40%). In the upper horizons of the cover soil, the concentration of these gases sharply decreased. Techniques for estimation of the methane-oxidizing activity in the cover soil of the landfill were tested. The rate of methane oxidation in the soil, the factor limiting methane emission from the surface of the site, correlated with the cell number of culturable methanotrophic bacteria. The method of indirect immunofluorescence revealed ten known species of methanotrophic bacteria in enrichment cultures obtained from samples of the cover soil. Our results also indicate the presence of unknown psychrotolerant methanotrophs that are active at the low temperatures characteristic of Moscow oblast.

The paper presents the results of a study of the impact of large-scale solid waste storage on ascariasis morbidity in the population. The use of sewage sediments as an organic soil fertilizer to grow strawberries and table greens is shown to substantially increase the risk of Ascaris infection in the population. Storage of solid domestic garbage on specialized dumping grounds does not lead to mass environmental pollution with geohelminthic eggs.

Operation of enterprise for radioactive waste processing and disposal does not influence negatively physical and mental development of children and adolescents residing in the area under observation. In some parameters, physical and mental development of children and adolescents residing in the area under observation surpasses that in reference area--that could be due to social and economic peculiarities.

The paper presents the results of sanitary and hygienic investigations whose reason was the situation established with the removal of dumping earth in the dwelling area of Mitino Microdistrict 8 gamma. The removed dumping earth found to have formaldehyde, benzenes, acetaldehyde, phenols, aromatic hydro carbons, polyaromatic compounds was a source of bad smelling substances that had entered the ambient air. A special study of the earth showed that it might yield volatile and bad smelling compounds, such as organic sulfides, aldehydes, mercaptans, ketones, etc. Their harmful health effects (during operations and in the late period) seem to be unlikely. When such work is under way, it is necessary to inform the population about possible consequences.

Based on the hygienic analysis of the currently available methods for decontamination and processing of solid waste from long-distance trains, the authors have developed a system for its collection and utilization. The hygienic aspects of the reconstruction and construction of railway objects are presented by taking into account the proposed system for refuse collection and processing.

The waste-water system of small localities is an important measure for their sanitary well-being. At present, the firm "Ekobios" produces and installs block-module plants for sewage treatment in small localities.

One of the most hygienic methods for the solid municipal waste to manage is the biothermal treatment with pyrolysis of uncompostable fractions and subsequent utilization of intermediate products. This scheme of municipal solid waste management has been realized in the Leningrad experimental factory for the mechanized treatment of municipal waste.

In the processing of the waste products of phosphorus containing fertilizer production, several major health-related factors were identified depending on the industrial site's peculiarities: unfavourable microclimate conditions (both cold and heat), relative temperature differences, noise and vibration caused by the equipment, semi-product's, additives' and finished product's dusts, fluorine- and phosphorus-containing substances' affects and poor illumination. The proposed data were used for health-related improvements in the occupational conditions.