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Examination covered 245 individuals and included characteristics of endocrine state of pulp and paper plant workers over 2011-2012, in comparison with data from 1990, as well as comparison with reference groups of male workers with no contact with chemical'industry in Arkhangelsk. Findings are both in main and reference groups general decrease in levels of cortisol, thyroxin;progesterone, testosterone, insulin, somatotropin and increased serum level of estradiol. With that, inside both groups, reliable tendencies to increased levels of cortisol, thyroxin, insulin, SSH and lower concentration of progesterone in the pulp and paper plant workers vs. the reference group members. Positive tendency was absence of abnormal concentrations of insulin, SSH and lower frequency of high cortisol levels in the pulp and paper plant workers nowadays.

Anaerobic microbial conversion of organic substrates to various biofuels is one of the alternative energy sources attracting the greatest attention of scientists. The advantages of biogas production over other technologies are the ability of methanogenic communities to degrade a broad range of substrates and concomitant benefits: neutralization of organic waste, reduction of greenhouse gas emission, and fertilizer production. Cellulose-containing materials are a good substrate, but their full-scale utilization encounters a number of problems, including improvement of the quality and amount ofbiogas produced and maintenance of the stability and high efficiency of microbial communities. We review data on microorganisms that form methanogenic cellulolytic communities, enzyme complexes of anaerobes essential for cellulose fiber degradation, and feedstock pretreatment, as biodegradation is hindered in the presence of lignin. Methods for improving biogas production by optimization of microbial growth conditions are considered on the examples of biogas formation from various types of plant and paper materials: writing paper and cardboard.

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.

Hydrolytic ability of laboratory enzyme preparations from fungus of the Penicillium genus was investigated using kraft pulp from nonbleached softwood and bleached hardwood cellulose as substrates. The enzyme preparations were shown to efficiently hydrolyze both softwood and hardwood cellulose. The yields of glucose and reducing sugars were 24-36 g/l and 27-37 g/l from 100 g/l of dry substrate in 48 h, respectively, and depended on the number of substrate grinding cycles.

The effect of cellocandin, an enzymatic preparation from Getrichum candidum 3C-106 with cellulolytic and xylanolytic activities, on defibring of waste paper and acceleration of desiccation of paper pulp was studied. It was shown that cellocandin accelerated defibring of waste paper to cellulose fibers and desiccation of cellulose suspension.

Sanitary-chemical, bacteriological and toxicological characterization of sediments in the regions of the pulp and paper mills sewage letting out are given. Methods of the analytical control are offered.

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.

The use of the Ames test for the analysis of industrial effluents from cellulose production and sewage waters varying in the degree of purification with the aid of a metabolic activation system from rat and fish liver with Salmonella strains TA 98 and TA 100 revealed a strong direct mutagenic effect of strain TA 100 in samples after cellulose chlorination. The multistage procedure of sewage water purification allows to remove practically completely the mutagenic substances. A simultaneous study of cytotoxic effects of industrial effluents on mammalian cells shows that the mutagenic activity is exhibited in not toxic concentrations. The urgency of a regular biological control over the genotoxicity of industrial effluents from the sulfate production of cellulose is under discussion.

The effect of paper thermal destruction on its luminescence spectra and luminescence excitation spectra in the spectral ranges of 400-550 nm and 250-450 nm, respectively, was studied. It is proposed to use the characteristic changes in the intensity and shape of the luminescence spectra as a criterion for the state of paper insulation of power transformers. On the basis of the analysis performed, it was concluded that when luminescence is excited at a wavelength of 360 nm, none of the main components of the paper can contribute to the recorded luminescence spectra. It is assumed that the resulting luminescence spectra are due to the emission of various impurities that enter the paper during its production.

Background. Development of technology for obtaining peracetic pulp from oat straw and its use in the production of one of the paper mass types. Objective. Determination of peracetic cooking technological parameters’ optimal values for oat straw peracetic cellulose quality indicators. Methods. The oat straw cooking was carried out with peracetic acid at 95 ± 1 °C from 90 to 180 min for hydromodulus 8:1 and 7:1, using a sodium tungstate catalyst. To determine the oat straw peracetic cellulose mechanical indexes, laboratory samples of paper weighing 70 g/m2 were made. Results. Technological parameters’ optimum values (temperature, cooking duration, hydromodulus, hydrogen peroxide and acetic acid concentration) for the oat straw delignification process were established. It is shown that the sodium tungstate catalyst addition to the cooking solution at a rate of up to 1 % of the plant raw material weight helps to reduce the lignin content in cellulose to 15 %. A diagram of the cellulose yield dependence on its residual lignin content for various methods of non-wood plant material species delignification is constructed. The high efficiency of the peracetic method for obtaining cellulose from non-wood plant raw materials, in particular from oat straw, has been confirmed. It is determined that the obtained peracetic cellulose from oat straw has high mechanical indexes. Conclusions. Oat straw peracetic cellulose can be used for the production of paper and cardboard mass types, in particular wrapping paper.