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Incidence of co-resistance to antibiotics and chlorine in bacterial biofilm of hospital water systems: Insights into the risk of nosocomial infections. J Infect Public Health 2023; 16 Suppl 1:210-216. [PMID: 37951730 DOI: 10.1016/j.jiph.2023.10.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Accepted: 10/26/2023] [Indexed: 11/14/2023] Open
Abstract
The presence of biofilms in drinking water distribution systems (DWDS) in healthcare settings poses a considerable risk to the biological security of water, particularly when the biofilm bacteria demonstrate antimicrobial resistance characteristics. This study aimed to investigate the occurrence of antibiotic-resistant bacteria (ARB) in biofilms within DWDS of hospitals. The chlorine resistance of the isolated ARB was analyzed, and then chlorine-resistant bacteria (CRB) were identified using molecular methods. Additionally, the presence of several antibiotic resistance genes (ARGs) was monitored in the isolated ARB. Out of the 41 biofilm samples collected from hospitals, ARB were detected in 32 (78%) of the samples. A total of 109 colonies of ARB were isolated from DWDS of hospitals, with β-lactam resistant bacteria, including ceftazidime-resistant and ampicillin-resistant bacteria, being the most frequently isolated ARB. Analyzing of ARGs revealed the highest detection of aac6, followed by sul1 gene. However, the β-lactamase genes blaCTX-M and blaTEM were not identified in the ARB, suggesting the presence of other β-lactamase genes not included in the tested panel. Exposure of ARB to free chlorine at a concentration of 0.5 mg/l showed that 64% of the isolates were CRB. However, increasing the chlorine concentration to 4 mg/l decreased the high fraction of ARB (91%). The dominant CRB identified were Sphingomonas, Brevundimonas, Stenotrophomonas, Bacillus and Staphylococcus with Bacillus exhibiting the highest frequency. The results highlight the potential risk of biofilm formation in the DWDS of hospitals, leading to the dissemination of ARB in hospital environments, which is a great concern for the health of hospitalized patients, especially vulnerable individuals. Surveillance of antimicrobial resistance in DWDS of hospitals can provide valuable insights for shaping antimicrobial use policies and practices that ensure their efficacy.
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Microbial indicators in municipal solid waste compost and their fate after land application of compost. JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2023; 21:85-92. [PMID: 37159731 PMCID: PMC10163187 DOI: 10.1007/s40201-022-00841-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 10/22/2022] [Indexed: 05/11/2023]
Abstract
Despite the extensive agricultural use of municipal solid waste (MSW) compost, there is little information about microbial characteristics of the MSW compost and fate of microorganisms following land application. This study was designed to determine the microbial quality and germination index (GI) of the MSW compost as well as fate of indicator microorganisms after application of MSW compost. The results showed a high fraction of samples are immature (GI < 80). In 27% and 16% of samples fecal coliforms and Salmonella were detected in a range exceeding the recommended value for unrestricted application of compost, respectively. HAdV was also detected in 62% of samples. Fecal enterococci were detected with relatively high concentrations in all samples and showed higher survival rate than other indicators in land-applied MSW compost. The results showed that climate condition significantly contributed to the decline of indicator bacteria in land-applied compost. The results highlight the need for further quality monitoring of compost to ensure that its application does not lead to environmental or human health problems. Furthermore, because of the high concentrations and high survival rate of enterococci in compost samples, they can be specifically proposed as an indicator microorganism for MSW compost quality monitoring.
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PM 2.5-associated bacteria in ambient air: Is PM 2.5 exposure associated with the acquisition of community-acquired staphylococcal infections? JOURNAL OF ENVIRONMENTAL HEALTH SCIENCE & ENGINEERING 2020; 18:1007-1013. [PMID: 33312619 PMCID: PMC7721920 DOI: 10.1007/s40201-020-00522-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 08/13/2020] [Indexed: 05/19/2023]
Abstract
Particulate matter (PM), a major component of air pollution, is an important carrier medium of various chemical and microbial compounds. Air pollution due to PM could increase the level of bacteria and associated adverse health effects. Staphylococci as important opportunistic pathogens that cause hospital- and community-acquired infections may transmit through air. This study aimed to obtain knowledge about the concentration of airborne bacteria as well as staphylococci associated with particulate matter with a diameter of less than 2.5 micrometers (PM2.5) in ambient air. The impact of meteorological factors including ultraviolet (UV) index, wind speed, temperature, and moisture on microbial concentrations was also investigated. Quartz filters were used to collect PM2.5 and associated bacteria in ambient air of a semiarid area. Airborne bacteria were quantified by culture method and Staphylococcus species identified by molecular methods. The mean (SD) concentration of PM2.5 and airborne bacteria was 64.83 (24.87) µg/m3 and 38 (36) colony forming unit (CFU)/m3, respectively. The results showed no significant correlation between the levels of PM2.5 and concentrations of bacteria (p < 0.05). Staphylococcus species were detected in 8 of 37 (22%) samples in a concentration from 3 to 213 CFU/m3. S. epidermidis was detected with the highest frequency followed by S. gallinarum and S. hominis, but S. aureus and methicillin-resistant Staphylococcus aureus (MRSA) were not detected. No significant correlation between the concentrations of bacteria with meteorological parameters was observed (p < 0.05). Our finding showed that, although the study area is sometimes subject to air pollution from PM2.5, the concentration of PM2.5- associated bacteria is relatively low. According to the results, PM2.5 may not be a source of community-associated staphylococcal infections.
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Effects of irrigation with secondary treated wastewater on physicochemical and microbial properties of soil and produce safety in a semi-arid area. WATER RESEARCH 2018; 144:356-364. [PMID: 30053626 DOI: 10.1016/j.watres.2018.07.047] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 07/15/2018] [Accepted: 07/18/2018] [Indexed: 05/21/2023]
Abstract
Water scarcity is becoming one of the largest problems worldwide. Agricultural reuse of wastewater has been considered a valuable and reliable alternative, alleviating the pressure on freshwater resources in arid and semi-arid regions such as the Middle East. Inadequate microbial quality of treated wastewater is a challenge for developing countries, which limits agricultural reuse of wastewater. This study assessed the impact of irrigation with secondary treated wastewater (STWW) on soil properties as well as the safety of various types of crops as compared with tap water (TW) irrigation through a furrow system. Total and fecal coliforms and Escherichia coli were monitored as indicator bacteria in STWW, irrigated soil and harvested crops. The presence of pathogenic E. coli O157, Salmonella and Shigella was also monitored in all samples using a combination of culture and molecular methods. The microbial quality of wastewater in terms of E. coli concentration (4.18 Log MPN/100 ml) failed to meet the world health organization (WHO) recommendation for irrigation of root and leafy crops (≤103 and ≤ 104E. coli per 100 ml for root and leafy crops, respectively). No significant effects on physicochemical properties of the soil irrigated with STWW was found in comparison with control plots, except for electrical conductivity (EC) and sodium adsorption ratio (SAR), which were slightly higher in STWW soil samples. Although the microbial quality of soil was affected by STWW irrigation, a relatively low concentration of E. coli was detected in soil. No microbial contamination in terms of E. coli was found on harvested maize and onion. E. coli contamination of lettuce and spring onion was found for both irrigation schemes. No STWW, soil or crop samples were found positive for pathogenic bacteria. According to the analyzed parameters, STWW could be safely used as an alternative source for irrigation of root and leafy crops.
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Synthesis and characterization of a novel stimuli-responsive magnetite nanohydrogel based on poly(ethylene glycol) and poly(N
-isopropylacrylamide) as drug carrier. J Appl Polym Sci 2018. [DOI: 10.1002/app.46657] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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PEGylated graphene oxide/Fe3O4 nanocomposite: Synthesis, characterization, and evaluation of its performance as de novo drug delivery nanosystem. Biomed Mater Eng 2018; 29:177-190. [DOI: 10.3233/bme-171721] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Estimation of health risks caused by exposure to enteroviruses from agricultural application of wastewater effluents. WATER RESEARCH 2017; 125:104-113. [PMID: 28841422 DOI: 10.1016/j.watres.2017.08.028] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Revised: 07/08/2017] [Accepted: 08/11/2017] [Indexed: 05/21/2023]
Abstract
Agricultural reuse of wastewater is a common practice worldwide, especially in arid and semiarid area due to the freshwater scarcity. Wastewater irrigation in the Middle East, one of the most water-stressed regions in the world, could be a key factor for socio-economic development, but the microbial contamination of untreated or partially treated wastewater is a serious public health concern. Potential transmission of enteric viral infections through wastewater reuse in agricultural activities represents a true health risk for exposed individuals. Accordingly, it is important to assess the health risks associated with wastewater reuse. A quantitative microbial risk assessment (QMRA) with Monte-Carlo simulation was used to estimate the annual risk of enterovirus (EV) infection and disease burden for farmers and consumers of wastewater-irrigated lettuce in Iran, a semiarid country in the Middle East region. Risk analysis was performed based on the measured concentrations of EV in effluent of two activated sludge wastewater treatment plants (WWTP). Wastewater effluent sampling was carried out over a nine-month period, and the presence of total and fecal coliforms and EV was determined. Fecal coliform bacteria were found at a high level exceeded the guideline limit for wastewater reuse in agriculture. EVs were detected in 40% of samples with the highest frequency in summer with a mean of 12 and 16 pfu/ml for WWTP-A and B, respectively. Statistical analysis showed no correlation between the concentration of fecal coliforms and EV. The estimated infection risk for EVs was 8.8 × 10-1 and 8.2 × 10-1 per person per year (pppy) for farmers of WWTP-A and -B, respectively which was about 2 log higher than the tolerable infection risk of 2 × 10-3 pppy. The estimated risk for lettuce consumers exhibited a lower level of infection and disease burden but higher than the guideline limits. The median disease burden for consumption of lettuce irrigated with activated sludge effluents was about 10-3 Disability Adjusted Life Years (DALY) pppy which exceeded the WHO guideline threshold of 10-4 DALY pppy. The results of study indicated that the activated sludge effluents require an additional reduction of EVs to achieve the acceptable level of risk for agricultural reuse of wastewater.
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Detection of antibiotic resistant Acinetobacter baumannii in various hospital environments: potential sources for transmission of Acinetobacter infections. Environ Health Prev Med 2017; 22:44. [PMID: 29165152 PMCID: PMC5664838 DOI: 10.1186/s12199-017-0653-4] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2016] [Accepted: 04/20/2017] [Indexed: 11/10/2022] Open
Abstract
Background Antibiotic resistant Acinetobacter baumannii has emerged as one of the most problematic hospital acquired pathogens around the world. This study was designed to investigate the presence of antibiotic resistant A. baumannii in various hospital environments. Methods Air, water and inanimate surface samples were taken in different wards of four hospitals and analyzed for the presence of A. baumannii. Confirmed A. baumannii isolates were analyzed for antimicrobial susceptibility and also screened for the presence of three most common OXA- type carbapenemase-encoding genes. Results A. baumannii was detected in 11% (7/64) of air samples with the highest recovery in intensive care units (ICUs). A. baumannii was also detected in 17% (7/42) and 2% (1/42) of surface and water samples, respectively. A total of 40 A. baumannii isolates were recovered and analysis of antimicrobial susceptibility showed the highest resistance towards ceftazidime (92.5%, 37/40). 85% (34/40) and 80% (32/40) of the isolates were also resistant to imipenem and gentamicin, respectively. Resistance genes analysis showed that 77.5% (31/40) strains contained OXA-23 and 5% (2/40) strains contained OXA-24, but OXA-58 was not detected in any of the strains. Conclusion Detection of antibiotic resistant A. baumannii in various samples revealed that hospital environments could act as a potential source for transmission of A. baumannii infections especially in ICUs. These results emphasize the importance of early detection and implementation of control measures to prevent the spread of A. baumannii in hospital environments.
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Electrically conductive nanofibrous scaffolds based on poly(ethylene glycol)s-modified polyaniline and poly(ε-caprolactone) for tissue engineering applications. RSC Adv 2016. [DOI: 10.1039/c6ra22280c] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The objective of this study was to design and development of electrically conductive nanofibrous scaffolds composed of PEGs-b-(PANI)4 and PCL for tissue engineering applications.
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Sewage sludge composting: quality assessment for agricultural application. ENVIRONMENTAL MONITORING AND ASSESSMENT 2015; 187:709. [PMID: 26508019 DOI: 10.1007/s10661-015-4940-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Accepted: 10/20/2015] [Indexed: 05/02/2023]
Abstract
In order to use sewage sludge (SS) composts in agriculture, it is extremely important to estimate the quality of compost products. The aim of this study was to investigate the quality of composted SS as a fertilizer and soil amendment especially in semi-arid areas. To determine the quality and agronomic value of the SS compost products, analyses on pH, electrical conductivity, organic matter content, C/N ratio, phytotoxicity, microbial load, and heavy metal content of composted anaerobically digested SS, with different proportions (1:1, 1:2, and 1:3 v/v) of green and dry plant waste, as bulking agents, were performed. The 1:2 and 1:3 mixtures of SS and green/dry plant waste were the most beneficial for composting, with final composts attaining high organic matter degradation and exhibiting low amounts of heavy metals, a relatively high germination index, and significant reduction of pathogens, suggesting the agricultural relevance of composted SS and green/dry plant waste at 1:2 and 1:3 (v/v) proportions. pH and electrical conductivity were also within the permissible limits. With respect to international standards, it appears that composted SS and green/dry plant waste at 1:2 and 1:3 proportions pose no threat to soil or plant quality if used in agriculture or land restoration.
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Modification of polythiophene by the incorporation of processable polymeric chains: Recent progress in synthesis and applications. Prog Polym Sci 2015. [DOI: 10.1016/j.progpolymsci.2014.11.004] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Monitoring of airborne bacteria and aerosols in different wards of hospitals - Particle counting usefulness in investigation of airborne bacteria. ANNALS OF AGRICULTURAL AND ENVIRONMENTAL MEDICINE : AAEM 2015; 22:670-3. [PMID: 26706974 DOI: 10.5604/12321966.1185772] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
INTRODUCTION AND OBJECTIVE The presence of airborne bacteria in hospital environments is of great concern because of their potential role as a source of hospital-acquired infections (HAI). The aim of this study was the determination and comparison of the concentration of airborne bacteria in different wards of four educational hospitals, and evaluation of whether particle counting could be predictive of airborne bacterial concentration in different wards of a hospital. MATERIALS AND METHOD The study was performed in an operating theatre (OT), intensive care unit (ICU), surgery ward (SW) and internal medicine (IM) ward of four educational hospitals in Isfahan, Iran. A total of 80 samples were analyzed for the presence of airborne bacteria and particle levels. RESULTS The average level of bacteria ranged from 75-1194 CFU/m (3) . Mean particle levels were higher than class 100,000 cleanrooms in all wards. A significant correlation was observed between the numbers of 1-5 µm particles and levels of airborne bacteria in operating theatres and ICUs. The results showed that factors which may influence the airborne bacterial level in hospital environments should be properly managed to minimize the risk of HAIs especially in operating theaters. CONCLUSIONS Microbial air contamination of hospital settings should be performed by the monitoring of airborne bacteria, but particle counting could be considered as a good operative method for the continuous monitoring of air quality in operating theaters and ICUs where higher risks of infection are suspected.
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Applicability of universal Bacteroidales genetic marker for microbial monitoring of drinking water sources in comparison to conventional indicators. ENVIRONMENTAL MONITORING AND ASSESSMENT 2014; 186:7055-7062. [PMID: 25023746 DOI: 10.1007/s10661-014-3910-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 06/30/2014] [Indexed: 06/03/2023]
Abstract
Water quality monitoring is essential for the provision of safe drinking water. In this study, we compared a selection of fecal indicators with universal Bacteroidales genetic marker to identify fecal pollution of a variety of drinking water sources. A total of 60 samples were collected from water sources. The microbiological parameters included total coliforms, fecal coliforms, Escherichia coli and fecal streptococci as the fecal indicator bacteria (FIB), Clostridium perfringens and H2S bacteria as alternative indicators, universal Bacteroidales genetic marker as a promising alternative fecal indicator, and Salmonella spp., Shigella spp., and E. coli O157 as pathogenic bacteria. From 60 samples analyzed, Bacteroidales was the most frequently detected indicator followed by total coliforms. However, the Bacteroidales assay failed to detect the marker in nine samples positive for FIB and other alternative indicators. The results of our study showed that the absence of Bacteroidales is not necessarily an evidence of fecal and pathogenic bacteria absence and may be unable to ensure the safety of the water. Further research, however, is required for a better understanding of the use of a Bacteroidales genetic marker as an indicator in water quality monitoring programs.
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Synthesis of conductive polyaniline-modified polymers via a combination of nitroxide-mediated polymerization and “click chemistry”. RSC Adv 2014. [DOI: 10.1039/c4ra00864b] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A new strategy for graft copolymerization of aniline onto polystyrene by a multi step process is suggested.
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Synthesis and characterization of polystyrene-graft-polythiophene via a combination of atom transfer radical polymerization and Grignard reaction. RSC Adv 2014. [DOI: 10.1039/c4ra01228c] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
For the first time, synthesis and characterization of polystyrene-graft-polythiopheneviaa combination of atom transfer radical polymerization and Grignard reaction is reported.
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Surveillance of Legionella species in hospital water systems: the significance of detection method for environmental surveillance data. JOURNAL OF WATER AND HEALTH 2013; 11:713-719. [PMID: 24334845 DOI: 10.2166/wh.2013.064] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Monitoring of hospital water systems to prevent and control nosocomial legionellosis is important from a public health perspective. This study was conducted to survey the prevalence of Legionella contamination of hospital waters. A total of 44 water samples from the hot-water system of 11 hospitals were tested for Legionella by a culture method and a nested polymerase chain reaction (PCR) assay with Legionella-specific primers to identify the more sensitive method. Some physicochemical parameters and heterotrophic plate counts of water samples for possible association with Legionella contamination were also determined. The contamination rate of hospitals in our study varied between 64% (eight of 11)-100% based on culture method and nested PCR, respectively. Of the 44 water samples examined, 23% were positive for Legionella spp. by the culture method, while the nested PCR assay using the primers LEG448-JRP revealed 66% of the water samples being positive. Given the importance of monitoring hospital water systems for the presence of Legionella spp., the present PCR assay proved highly applicable for practical and sensitive surveillance of Legionella in such water systems. In addition, rapid monitoring of Legionella contamination could eliminate the potential exposure of high-risk patients through effective control measures.
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Graft copolymerization of thiophene onto polystyrene synthesized via nitroxide-mediated polymerization and its polymer − clay nanocomposite. POLYM INT 2013. [DOI: 10.1002/pi.4513] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Chemical modification of polyaniline by N-grafting of polystyrenic chains synthesized via nitroxide-mediated polymerization. J BRAZIL CHEM SOC 2012. [DOI: 10.1590/s0103-50532012000600003] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Microbial quality of water in dental unit waterlines. JOURNAL OF RESEARCH IN MEDICAL SCIENCES : THE OFFICIAL JOURNAL OF ISFAHAN UNIVERSITY OF MEDICAL SCIENCES 2009; 14:297-300. [PMID: 21772899 PMCID: PMC3129099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/03/2009] [Accepted: 06/15/2009] [Indexed: 11/12/2022]
Abstract
BACKGROUND Dental unit waterlines (DUWLs) are ideal environment for development of microbial biofilms. Microbial contamination of water in DUWLs is thought to be the result of biofilm formation as it could serves as a haven for pathogens. The aim of this study was to assess microbial quality of water in dental unit waterlines of dental units located at the dental school of Isfahan University of Medical Sciences. METHODS Water samples were collected from air/water syringe and high-speed handpiece. Generally, 100-200 ml water samples were collected aseptically in sterile containers with sodium thiosulfate at the beginning of the day after a 2 minute purge. Samples were transferred to the laboratory in insulated box with cooling packs and examined for total viable heterotrophic bacteria and fungi. RESULTS The heterotrophic plate count levels were significantly exceeded the American Dental Association recommendations for DUWL water quality (< 200 CFU/ml), in both air/water syringe (84%, CFU/ml: 500-20000) and high-speed handpiece (96%, CFU/ml: 710-36800) samples. However, there was no significant difference between the level of contamination in the air/water syringe and high-speed handpiece. Fungi were found in 28% and 36% of air/water syringe and high-speed handpiece samples, respectively; and filamentous fungi were the most frequently isolated fungi. CONCLUSIONS DUWLs should be subjected to routine microbial monitoring and to a decontamination protocol in order to minimize the risk of exposure to potential pathogens from dental units.
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Predictive indicators of the safety of swimming pool waters. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2009; 60:3101-3107. [PMID: 19955633 DOI: 10.2166/wst.2009.746] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Many outbreaks related to swimming pools could have been prevented or reduced if the pool had been well managed and effectively monitored. The aim of this study was to evaluate physicochemical and microbial parameters that can be proposed as an indicator for the safety of swimming pools. A total of 234 water samples, over a 10-month period in 2006-2007, were collected from indoor swimming pools in Isfahan. All water samples were analyzed for physicochemical and microbial parameters including temperature, pH, turbidity, conductivity, free chlorine, heterotrophic plate count (HPC), total (TC) and fecal coliforms (FC), fecal streptococci (FS) Staphylococcus aureus (Sa) and Pseudomonas aeruginosa (Pa). The highest isolation of microbial indicators was for total coliforms (38%) and the lowest for fecal streptococci (3%). The correlation analyses indicated that free chlorine concentration had a significant negative relationship with the heterotrophic bacteria population and total coliforms. Total coliforms presented a significant correlation with the other microbiological indicators. The results clearly showed that the hygienic quality of the swimming pools was dependent on the efficacy of disinfection. Thus, the free chlorine and pH were good operational indices for the quality control of swimming pools and must be maintained in the recommended range to ensure optimal disinfection. The results also showed that TC and HPC were reliable and practical indicators for routine quality surveillance and assessment of the efficiency of the disinfection process and safety of swimming pools.
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