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In the paper there are presented data of field observations of the spectrum of viruses, contained in the waste waters. The studies were performed on the territory of the city and the territory unfavorable for hepatitis A. In the territory of the big city by RT-PCR in the waste liquid the enterovirus RNA was detected in 45% of samples; astroviruses--90%; noroviruses--80% and 15% of rotaviruses. Samples from 2 wells were slightly positive for the presence of HCV RNA A. In the waste liquid on the territory, unfavorable for viral hepatitis A, in 100% of the samples there were determined noro- and astroviruses RNA and adenovirus DNA, in 75%--enterovirus RNA; 50%--HAV RNA and a 25%--rotavirus RNA.

The authors propose a new heterogeneous photo sensitizer containing aluminum tetrakis [bis(cholinyl)phenylthio)] phthalocyanine grafted onto silica as an active phase. A poliovirus type 1 LSc2ab and RNA-containing phage MS2 model was used to show that the sensitizer had photo decontaminating activity against viruses and may be used to purify water from viral contamination. The mechanism for removal of viruses from water is two-step and involves the adsorption of the virus on the heterogeneous sensitizer particles and the photodynamic inactivation of the adsorbed virus.

The paper outlines materials on how to improve a method for indication of water viral pollution in different water objects of the environment, by applying a MFM filtration module based on tangentially radial-mode water microfiltration and viral concentration on the positively charged membranes, by using the secondary stage of concentration. Experimental and full-scale studies have demonstrated that this method for virus isolation has a high effectiveness and is based on the employment of the materials made in Russia. This determines its rapid introduction into the system for the sanitary-virological monitoring of practical laboratories of various departments, which will favor the higher efficiency of epidemiological surveillance as an integral part of nonspecific prophylactic measures of virus infections of water etiology.

In the buccal epithelial micronuclear test, only the higher frequency of cells with any nuclear degenerative changes is considered to be attributable to the adverse influence of environmental factors. Comprehensive examination of 223 children of 5-7 years of age, going to kindergartens and schools has indicated that the frequency of cells with nuclear chromatin condensation and incomplete nuclear lysis decreased when ambient air contamination was increased in the territories of children's establishments and when the child's throat was contaminated with Staphylococcus aureus or the pharyngeal resident microflora inhibited. Some poor conditions of the nasal and buccal mucosae were also associated with the increase or decrease of cell frequencies. It is suggested that nuclear chromatin condensation and nuclear lysis (rather than other signs of cell degeneration and death) reflect natural cell aging. A moderate toxic effect causes epitheliocytic physiological development retardation and a more intensive effect accelerates aging of cells and induces their death.

The paper describes an accelerated procedure for isolating enteric viruses and a scheme for evaluating the viral contamination of pure waters, which involves the concentration of the viruses from the great water volumes by means ofa MFM 0142 membrane module with tangential filtration through an electropositive membrane (MMK) with a pore size of 0.2 microm, followed eluent determination of RNA of viruses by RT-PCR in combination with coliphages or ICC by RT-PCR.

Hygienic standardization of soil sarin, soman, and Vx levels established the threshold and subthreshold concentrations of the agents from the general sanitary, translocational, and migratory water and migratory air safety indices. Substantiation of their maximum allowable concentrations (MAC), the limiting safety index is a migratory air index for soman and sarin and a migratory water index for Vx. Soil MACs of sarin, soman, and Vx are 2 x 10(-4), 1 x 10(-4), and 5 x 10(-5) mg/kg, respectively.

The article is dedicated to present-day problems of sanitary-virologic monitoring of water with different degree of pollution. The authors assess some indirect indicators of viral contamination of water and present perfected methods of water monitoring such as PCR, OT-PCR, and OT-PCR integrated with tissue culture for detecting viral RNA and DNA.

Quantitative relationships were studied between the indicators (common coliform bacteria (CCP), glucose-positive bacteria (GPB), thermoduric bacteria (TDB), coliform bacteria, enterococci, clostridia, coliphages) and the opportunistic (Pseudomonas aeruginosa, Proteus, Klebsiella) and pathogenetic (Salmonella and intestinal viruses) microorganisms at the stages of effluent purification and decontamination, in processes of self-purification in the water reservoirs and of water preparation at water-supplying stations, as well as in the association with the incidence of acute intestinal infections of bacterial and viral genesis in different climatic zones of the country. Salmonella and the opportunistic bacteria of the Enterobacteriaceae family and Pseudomonas aeruginosa were found to be highly resistant to detoxifying agents and environmental factors, adaptable, able to reproduce in pure water, to long survive in underground waters, and to accumulate when water is desalinated at the erections. The cases of intestinal infections were found in the population using the portable water of the standard quality in terms of E. coli, TDB, CCB, and enterococci. In this case only the wider integral index of GPB, which includes the indices of E. coli, TDB, CCB, as well as lactose-negative pathogenic and opportunistic species retains its sanitary significance in terms of all signs and is a reliable indicator of the potential epidemic hazard of drinking water use. Long-term studies have provided evidence for the sanitary value of coliphages as indicators of viral drinking water contamination.

The authors made an experimental study of the efficiency of water purification procedures based on the combined use of active chlorine and coagulants and hygienically evaluated the procedures. The study included the evaluation of water disinfection with various coagulants and active chlorine; the investigation of the processes of production of deleterious organic chlorine compounds; the assessment of the quality of water after its treatment. The coagulants representing aluminum polyoxychloride: RAX-10 (AQUA-AURATE 10) and RAX-18 (AQUA-AURATE 18), and aluminum sulfate, technically pure grade were tested. The treatment of river water with the coagulants RAX-10 and RAX-18, followed by precipitation, filtration, and chlorination under laboratory conditions, was shown to result in water disinfection to the levels complying with the requirements described in SanPiN 2.1.4.1074-01. RAX-18 showed the best disinfecting activity against total and heat-tolerant coliform bacteria, but also to the highly chlorine-resistant microrganisms--the spores of sulfite-reducing Clostridia, phages, and viruses. Since the coagulants have an increased sorptive capacity relative to humus and other organic substances, substitution of primary chlorination for coagulant treatment may induce a reduction in the risk of formation of oncogenically and mutagenically hazardous chlorinated hydrocarbons.

The paper presents the data of Russian and foreign authors, as well as these author's findings of the significance of coliphages as indicators of viral contamination of drinking water. Coliphages may be used as indicators of viral drinking water contamination and for evaluation of the efficiency of drinking water purification in waterworks.

On the territory of town Perm there are some factors of hygienic, climatic and technical nature which yearly influence microbial pollution of drinking water and seasonal incidence of intestinal infections of obscure etiology. It was shown in several years investigations.

Bound chlorine in doses 0.8-1.2 mg/l does not inactivate viruses in water. Chlorine can be active against hepatitis A viruses in concentration not less than 4.2 mg/l with the virion content in water 10(5)/ml and at least 20 min exposure.

It has been found out that a coli-phage is a more reliable indirect indicator of viral pollution of drinking water that the existing indirect bacterial indicators. Coli-phages concentration in drinking water on the level of single PFU/1 is evidence of disturbances in the barrier function of water-treatment facilities with respect to viral microflora and of the possible epidemic danger of water with respect to viral infection. The absence of coli-phages in I 1 of water sample should be considered the standard level of coli-phages of drinking water.