Domestic swimming pools. Water systems

The efficacy of electrolytically generated copper and silver ions (400 and 40 μg/L, respectively) was evaluated separately and in combination with free chlorine (0.2 and 0.3 mg/L) for the inactivation of coliphage MS-2 and poliovirus type 1 in water at pH 7.3. The inactivation rate was calculated as log10 reduction/min: k = −(log10Ct/C0)/t. The inactivation of both viruses was at least 100 times slower in water containing 400 and 40 μg/L copper and silver, respectively (k = 0.023 and 0.0006 for MS-2 and poliovirus, respectively), compared with water containing 0.3 mg/L free chlorine (k = 4.88 and 0.036). Significant increases in the inactivation rates of both viruses were observed in test systems containing 400 and 40 μg/L copper and silver, respectively, with 0.3 mg/L free chlorine when compared with the water systems containing either metals or free chlorine alone. Poliovirus was approximately 10 times more resistant to the disinfectants than coliphage MS-2. This observation suggests either a synergistic or an additive effect between the metals and chlorine for inactivation of enteric viruses. Use of copper and silver ions in water systems currently used in swimming pools and spas may provide an alternative to high levels of chlorination. Key words: enteric viruses, poliovirus, coliphage MS-2, bacteriophage, disinfection, inactivation, copper, silver, chlorine.

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Domestic swimming pools. Water systems

10.3403/30294823u ◽

2016 ◽

Keyword(s):

Water Systems ◽

Swimming Pools

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Persistent Cutaneous Infection Due to Mycobacterium Immunogenum, a Relatively Novel Species

SKIN The Journal of Cutaneous Medicine ◽

10.25251/skin.2.1.11 ◽

2018 ◽

Vol 2 (1) ◽

pp. 69-74

Author(s):

Skyler M White ◽

Katrina N Kesterson ◽

Michael G Wilkerson

Keyword(s):

Nontuberculous Mycobacteria ◽

Novel Species ◽

Water Systems ◽

Distilled Water ◽

Healthy Patient ◽

Swimming Pools ◽

Cutaneous Infection ◽

Cutaneous Infections ◽

Municipal Water ◽

Minimal Scar

Mycobacterium immunogenum is a species of nontuberculous mycobacteria (NTM) that has been recently identified as the cause of cutaneous infections.1-3 Historically, the majority of NTM infections were attributed to contamination of municipal water systems due to inadequate equipment sterilization. Many of these organisms have been found to grow in distilled water and display resistance to chlorine, formaldehyde, mercury, and standard disinfectants.4 In the environment, M. immunogenum has been isolated in swimming pools and adjacent showers.5 A limited number of cutaneous infections with Mycobacterium immunogenum have been reported, and an even smaller number of cases have been reported in immunocompetent individuals. We report a case of a persistent cutaneous infection with M. immunogenum in a previously healthy patient successfully treated with clarithromycin 250 mg twice daily for eight weeks. After treatment, the patient remained free of infection and only a minimal scar remained.

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Effecting Partial Elimination of Isocyanuric Acid from Swimming Pool Water Systems

Water ◽

10.3390/w11040712 ◽

2019 ◽

Vol 11 (4) ◽

pp. 712

Author(s):

Marina Corral Bobadilla ◽

Eliseo Vergara González ◽

Rubén Lostado Lorza ◽

Fátima Somovilla Gómez

Keyword(s):

Acid Concentration ◽

Water Systems ◽

Swimming Pool ◽

Swimming Pools ◽

Raw Water ◽

The European Union ◽

Water Network ◽

Pool Water ◽

Isocyanuric Acid ◽

Swimming Pool Water

It is essential to disinfect the water in swimming pools in order to deactivate pathogenic microorganisms. Chlorination of swimming pool water provides rapid and long-lasting disinfection, but leads to the formation of potentially toxic compounds, including isocyanuric acid, that are used to stabilize chlorine in pool water. Hygiene and health guidelines require an isocyanuric acid concentration in swimming pools of 25 to 75 ppm and that there be no level in excess of 100 ppm. This paper provides a new method to partially remove isocyanuric acid from the water of swimming pool systems with the use of melamine-based reagents. A melamine-photometry process stabilizes the isocyanuric acid. The melamine-based reagent that is added to the raw water reacts with the isocyanuric acid and forms a precipitated salt. The reaction also creates turbidity that is proportional to the isocyanuric acid concentration in the water. It was noted in this study that the optimum functioning range of melamine doses in the raw water was 0.04 to 0.06 g/L and that the reduction of isocyanuric acid in raw water increased as the dose of melamine was increased. Thus, it is necessary to obtain an estimate of the dose of melamine that is necessary to reduce the isocyanuric acid in the water without needing to add fresh water from the network to dilute it. Finally, it can be stated that eliminating isocyanuric acid that has accumulated in a pool’s water by treatment with melamine provides an efficient process, as it eliminates the amount of isocyanuric acid that is necessary to conform to the human health criteria of the European Union Directive 2006/7/EC. Treatment with melamine also reduces water network consumption and sewer discharge by successive purges that eventually will become unnecessary. Therefore, this proposed method is environmentally and economically beneficial.

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The effect of temperature and chlorine residual on the presence of Legionella spp. in water systems of public and tourist facilities

Journal of Health Sciences ◽

10.17532/jhsci.2017.413 ◽

2017 ◽

Vol 7 (1) ◽

pp. 50-58 ◽

Cited By ~ 2

Author(s):

Adna Besic ◽

Zarema Obradovic ◽

Adisa Dautbegovic ◽

Amina Obradovic

Keyword(s):

Membrane Filtration ◽

Tap Water ◽

Statistical Significance ◽

Water Systems ◽

Residual Chlorine ◽

Swimming Pools ◽

Filtration Method ◽

Heating Systems ◽

Significant Difference ◽

Free Residual Chlorine

Introduction: Legionella bacteria are ubiquitous microorganisms mostly found in artificial water environments, especially those which produce aerosol, such as swimming pools, saunas, and spas. Development of Legionella depends on several factors, including water temperature and chlorine. The aim of this study was to evaluate the occurrence of Legionella spp. to the temperature and free residual chlorine in tap water, water from fountains, swimming pools, cooling and heating systems. Methods: We collected 238 samples of water taken from different places and analyzed the presence of Legionella spp. by BAS EN ISO 11731-2:2009 - Water quality – Detection and enumeration of Legionella - Part 2: A direct membrane filtration method for waters with low bacterial counts, as samples were the waters with low expectancy of bacterial contamination compared to the temperature and free residual chlorine. The X2 test was used to show statistical significance. Results: Legionella spp. was detected in 18.62% of tap water and in 8.82% samples of water taken from fountains, swimming pools, and cooling and heating systems. The highest number of positive samples were detected in waters with the temperature higher than 20°C and lower than 50°C. The highest number of positive samples were reported by the concentration of free residual chlorine lower than 0.2 mg/l. The X2 test showed a statistically significant difference between positive and negative results for the presence of Legionella spp. among three groups of water samples. Conclusion: The research has shown a connection between environmental factors and the presence of Legionella spp. in the water systems of public and tourist facilities.

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