Introduction. The increasing bacterial contamination of water bodies requires an increase in water quality control’s reliability to ensure epidemic safety against waterborne infections. Therefore, researchers in both Russia and Europe came to the conclusion that it is necessary to search for indicator microorganisms that can more accurately suggest the presence of pathogens. microorganisms in water than traditional indicators. The aim of the study was to justify the introduction of indicator indices of fecal contamination “generalized coliform bacteria” and Escherichia coli to assess the safety of drinking water Material and methods. The article provides an analysis of domestic and international regulatory documents and literary materials regulating the quality of drinking water in terms of sanitary and microbiological indicators and assessment criteria. The results of many years of experimental and field research carried out by research organizations and practical organizations of the Federal Service for Supervision of Consumer Rights Protection and Human Welfare are presented. Results. On the territory of Russia, “general coliform bacteria,” is one of the indicator indices chosen according to the fermentation of lactose, determine the safety of drinking water. The water does not take into account pathogenic bacteria (Salmonella, Shigella) and a number of lactose-negative opportunistic bacteria, causative agents of intestinal infections. The study of microorganisms isolated from the feces of patients confirms the frequency of occurrence of lactose-negative microorganisms to varying from 20 to 100% of strains. With an annual trend towards a decrease in the percentage of non-standard drinking water samples in terms of microbiological indices, general intestinal infections (GII) of unknown etiology increase, i.e. risk of GII. If the quality of drinking water does not correspond to thermotolerant coliform bacteria (TCB), 95% of samples contain E. coli. Therefore, the determination of E. coli more reliably indicates the intake of fresh fecal contamination and provides efficiency in taking measures to eliminate an unfavorable situation than TCB. Conclusion. Reasons are given for the introduction of more reliable microbiological indicators of water safety control, such as - “generalized coliform bacteria” with the preservation of the abbreviation GCB, combining both lactose-positive and lactose-negative bacteria, determined by the sign of glucose fermentation, negative oxidase test and negative stain according to Gram and E. coli as an indicator of recent faecal contamination, which will allow the assessment of water quality for a wide range of bacteria of the order Enterobacterials, corresponding to the modern taxonomy of Enterobacteriaceae NCBI, will ensure harmonization with international requirements and the safety of drinking water for the population.
Introduction. The proposed criteria for the sanitary-bacteriological assessment of the quality of tap water must ensure its epidemic safety. In conditions of intensive bacterial contamination of water bodies, a special role is played by the barrier function of water treatment plants in relation to infectious agents. The overall quality of microorganisms is the pronounced resistance in the aquatic environment, primarily resistance to a number of chlorine-containing disinfectants, which guarantee the preservation of the population in drinking water undergone a water treatment system. Therefore, it is necessary to consider other possible ways of disinfection, such as ultraviolet irradiation. Determination of the effective dose of ultraviolet (UV) disinfection against bacterial, viral and parasitic contamination of drinking water. Material and methods. Tap water was used as model water for research. The effectiveness of UV irradiation with doses of 25, 40, 60 mJ / cm2 against microorganisms was studied. Results. In the course of the work, it was established that the UV disinfection technology with a dose of at least 25 mJ/cm2 can be recommended as a disinfection method when used in conjunction with chlorination. Conclusion. In water treatment technology, a dose of at least 25 mJ/cm2 of UV irradiation can be recommended as a method of disinfecting water in case of microbial contamination by bacteria and viruses at a concentration not exceeding nˑ102 cells/virions in 100 ml, and at a concentration of microbiological contamination nˑ103 cells/virions in 100 ml of water, the use of UV disinfection can be recommended only in conjunction with chlorination and with the provision of indices on the residual chlorine in the distribution network before serving to the consumer. The presented scheme will increase the barrier role of water treatment facilities with respect to viral and bacterial contamination, provide a prolonged decontamination effect, contributing to the suppression of bacterial growth in breeding nets and limit the level of parasitic water contamination during water treatment.
There was executed the assessment of the method of the detection and identification of sanitary-indicative microorganisms in water samples with the use of test systems IDEXX manufactured by IDEXX Laboratories, Inc (USA), based on the use of chromogenic culture media and reagents in accordance with the methodology developed by the manufacturer. IDEXX method was found not to be inferior to the reference methods of water analysis applied in Russia and in international practice. Comparative evaluation of crops showed the consistency of results, as in the study of contaminated water with natural microbiocenoses and water modeling of water bodies, contaminated by daily cultures test microganisms. The method allows reduce time of an analysis due to the exclusion of the biochemical reactions (oxidase activity, fermentation of carbohydrates, formation of indole, etc.) needed to determine species of microorganisms, and to obtain the final result of the analysis after 24 hours. On the basis of obtained results test systems IDEXX Laboratories (USA) may be applied on the territory of the Russian Federation for the assessment of water quality according to sanitary-microbiological indices
There were identified priority pollutants in water of the Moscow river below the city (petroleum products, lead, cadmium, zinc, copper; anionic surfactants), which can affect the natural microbiocenosis of surface water. The presence in surface waters heavy metals - cadmium in a concentration of 4 MPC for fishery purposes, of lead at a concentration of 5 MPC for fishery purposes, oil at a concentration of 49 MPC, zinc at a concentration of 10 MPC for fishery purposes, anionic surfactants at the concentrations below the MPC, and also at excess of MPC by 5 times for chlorides, nitrites and nitrates to a large extent was established to affect the viability of indicator bacteria - coliforms, E. coli, enterococci, while maintaining in the water of pathogenic bacteria - Salmonella and parasitic pathogens living Entamoebae spp. and cystic viable vegetative forms of pathogenic protozoa Flagellata spp. and viable helminth eggs Larvae spp.
1 Федеральное государственное бюджетное учреждение «Центр стратегического планирования и управления медико-биологическими рисками здоровью» (ФГБУ «ЦСП») Минздрава России 2
The increasing chemicalization of production and life leads to the pollution of water bodies by chemicals, the effect of which on the micro - and macro - organisms is poorly understood. This section of the study in sanitary bacteriology is becoming ever more topical and is an important task of modern hygienic science. One of complicacies of the study of the problem is related with the fact that the presence of only experimental data fails to be sufficient, as the impact of any given chemical substance on different bacteria in the experiment does not mean that under natural conditions, similar results will be obtained. One reason for this may be the inhibitory effect of the given chemical on biological properties of bacteria, while in field conditions in the water several chemicals interacting with each other can exist. In this regard, the aim of the work was to assess the indicator value of sanitary and microbiological indices of epidemic hazard of water use in conditions of chemical pollution of surface water bodies.
The used methodology of the scientific substantiation of indicators is in the establishment of the conformity of laws of vital activity of indicator and pathogenic microorganisms in the real conditions of the action of the complex of factors, including disinfecting agents. In the one water sample simultaneously there were determined both the general indicator (GICB), thermotolerant (TTCB), glucose positive (GPCB) coliform bacteria, E.coli. On the base of long-term research in the various regions of the Russian Federation, as well with bearing in mind the analysis of domestic and foreign data, comparing the water quality and the incidence of intestinal infections in population it is recommended to use the index of determination of the total number glucose positive coliform bacteria (GPCB), which brings together a much broader range of bacteria of the Enterobacteriaceae family in comparison with total coliform bacteria (TCB) and thermotolerant coliform bacteria (TTCB) and warrants the absence in the test volume of water as an indicator lactose positive (E.coli, TCB, TTCB) and pathogens (salmonella) and potentially pathogenic bacteria which do not ferment lactose. Proposed index of GPCB is shown to allow to assess epidemiological risks not only more accurate, but also more efficiently without increasing the cost performance of bacteriological research.
Criterion of the epidemic safety of drinking water is the absence of pathogenic and potentially pathogenic microorganisms. Currently, water quality control is performed in terms of the index of total coliform bacteria (TCB). TCB index oriented to the labile lactose sign has not sufficient relevance in the determination of the degree of the epidemic danger in the water use in relation to Salmonella and potentially pathogenic microorganisms. The frequency of detection of GCB in standard quality of drinking water as well as the application of the methodology for the assessment of the microbial risk of the occurrence of bacterial intestinal infections with the use of integral index--GCB, provide the most reliable prediction of risk in the occurrence of water-caused intestinal infections and more objectively reflect the epidemiological importance of drinking water in their distribution among the population. Proceeding from the data obtained, it is advisable to carry out the quality control of drinking water with the use of the broader indicator index GCB- detected from basic signs of the Enterobacteriaceae family--glucose fermentation and oxidase test and oxidase test.
Promising application of nanoparticles and nanomaterials is the creation of sanitary hygienic means of new generation used for disinfection of water and indoor surfaces of mass use, furniture, sanitary technical equipment by virtue of modifying traditional materials to bring them effective biocidal properties, and for the development of methods in vitro for assessment their toxicity In this paper the possibility of the use various forms of silver, copper and aluminum as disinfectant for bacterial test organisms in the aquatic environment and assess their toxicity on biological models of continuous culture of BGM cells (a stable line of African green monkey kidney cells) and HEp-2 (Human epithelial type 2 (HEp-2) cells, derived from a human laryngeal carcinoma) is considered.
The analysis of literature data was carried out and performed research justifying the epidemic value of detection in water P. aeruginosa in drinking and domestic water use. The were revealed features of the vital activity of P. aeruginosa in water bodies as opposed to conventional microbiological indicators. It was shown that the coliform group indices can not guarantee the epidemic safety of drinking water use in relation to P. aeruginosa. The data obtained justify the need for the introduction of P. aeruginosa as an additional index in monitoring the water quality of centralized and decentralized water supply.
The analysis of literature data was carried out and performed research justifying the epidemic value of detection in water P. aeruginosa in drinking and domestic water use. The were revealed features of the vital activity of P aeruginosa in water bodies as opposed to conventional microbiological indicators. It was shown that the coliform group indices can not guarantee the epidemic safety of drinking water use in relation to P aeruginosa. The data obtained justify the need for the introduction of P aeruginosa as an additional index in monitoring the water quality of centralized and decentralized water supply.
Москва The analysis of literature data was carried out and performed research justifying the epidemic value of detection in water P. aeruginosa in drinking and domestic water use. The were revealed features of the vital activity of P. aeruginosa in water bodies as opposed to conventional microbiological indicators. It was shown that the coliform group indices can not guarantee the epidemic safety of drinking water use in relation to P. aeruginosa. The data obtained justify the need for the introduction of P. aeruginosa as an additional index in monitoring the water quality of centralized and decentralized water supply. Key w ords: bacteria index, regulation, Pseudomons aeruginosa, features of vital activity, auxiliary indicator of the quality of drinking water.
For the purpose of harmonization of microbiological and parasitological indices and benchmarks there was performed the comparative analysis of the requirements for the quality of drinking water in respect of the epidemic safety on the basic regulations of Russia, the Directive Council of the European Union EU, WHO, the United States, Canada, Australia, Finland, Sweden, Brazil, France, Japan and China. As a result, there were revealed the priority bacteriological, virological and parasitological parameters: E. coli--indicator of recent fecal contamination, coliforms, heterotrophic bacteria colony count (Heterotrophic plate count), which is in the water legislation of the Russian Federation is characterized as total bacterial count (TBC), being an integral index of the quality of wastewater treatment technologies and hygienic condition of the water supply systems, coliphages as an indicator of viral contamination. In the Guidelines for drinking-water quality control, WHO and a set of countries there is recommended a more wide range of indicators: enterococci, Clostridium perfringens, Pseudomonas aeruginosa, enteroviruses, parasitological indices. With aim of harmonization of the requirements for the quality of drinking water in the Russian Federation with international approaches to the revision of the Sanitary Regulations and Norms (SanPin) 2.1.4.1074 into the project there are introduced priority indicator parameters of bacterial, viral and parasitic contamination of water, evidence-based guidelines.
For the purpose of harmonization of microbiological and parasitological indices and benchmarks there was performed the comparative analysis of the requirements for the quality of drinking water in respect of the epidemic safety on the basic regulations of Russia, the Directive Council of the European Union EU, WHO, the United States, Canada, Australia, Finland, Sweden, Brazil, France, Japan and China. As a result, there were revealed the priority bacteriological, virological and parasitological parameters: E. coli -indicator of recent fecal contamination, coliforms, heterotrophic bacteria colony count (Heterotrophic plate count), which is in the water legislation of the Russian Federation is characterized as total bacterial count (TBC), being an integral index of the quality of wastewater treatment technologies and hygienic condition of the water supply systems, coliphages as an indicator of viral contamination. In the Guidelines for drinking-water quality control, WHO and a set of countries there is recommended a more wide range of indicators: enterococci, Clostridium perfringens, Pseudomonas aeruginosa, enteroviruses, parasitological indices. With aim of harmonization of the requirements for the quality of drinking water in the Russian Federation with international approaches to the revision of the Sanitary Regulations and Norms (SanPin) 2.1.4.1074 into the project there are introduced priority indicator parameters of bacterial, viral and parasitic contamination of water, evidence-based guidelines.
Promising application of nanoparticles and nanomaterials is the creation of sanitary hygienic means of new generation used for disinfection of water and indoor surfaces of mass use, furniture, sanitary technical equipment by virtue of modifying traditional materials to bring them effective biocidal properties, and for the development of methods in vitro for assessment their toxicity. In this paper the possibility of the use various forms of silver, copper and aluminum as disinfectant for bacterial test organisms in the aquatic environment and assess their toxicity on biological models of continuous culture of BGM cells (a stable line of African green monkey kidney cells) and HEp-2 (Human epithelial type 2 (HEp-2) cells, derived from a human laryngeal carcinoma) is considered
Water samples and surface swabs from 15 Moscow public indoor swimming pools (SP), where disinfection was carried with the use of chlorine reagents, were studied and excess of bacteriological indicators standards was revealed, infestants of fungous skin and nails diseases were allocated. The research results showed both the absence of epidemic significant information value of bacteriological indicators in relation to infestants of fungous diseases and discrepancy of efficiency of existing recommendations for disinfection actions to requirements on providing sanitary-and-epidemiologic safety of SP visitors.
Due to intensive anthropogenic pollution of water environment generally accepted indicators of epidemic security of water bodies - common bacteria and thermotolerant coliform bacteria do not always permit to obtain an objective characterization of bacterial contamination of tap water. From the point of view of authors the integral index - glucose positive coliform bacteria most adequately reflect the sanitary-hygienic and epidemiological situation of water bodies. In monitoring for bacterial quality of tap water it is advisable to determine glucose positive coliform bacteria, that will provide the relevance of estimation of the epidemiological safety of water use. According to the method developed by the authors the calculation of the index of population risk of acute intestinal infections occurrence in dependence on the quality of tap water in Azov and Tsimlyansk towns.