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Objectives To understand the distribution level and health risk of disinfection by-products of drinking water in cities of China, and to provide references for drinking water safety management. Methods By systematically searching the literatures published from 2009 to 2019, the effective data were extracted and the exposure levels of disinfection by-products of drinking water in China was statistically analyzed. The health risk assessment model recommended by EPA was used to conduct risk assessments on THMs and HAAs disinfection by-products. Results The levels of various disinfection by-products were as follows: trihalomethane > haloacetic acid > haloacetonitrile > chloral hydrate > haloketones > nitrosamines. The main disinfection by-products in drinking water in southern China were higher than those in northern China. The total amount of disinfection by-products produced by liquid chlorine disinfection was higher than other disinfection methods. Conclusion The carcinogenic risk of various disinfection by-products in domestic urban drinking water was higher than the acceptable EPA level (1×10-6 ). Sodium hypochlorite disinfection instead of liquid chlorine disinfection was able to effectively reduce the health risk of disinfection by-products to humans. The health risk of the exposure to pollutants in drinking water was higher in children than in adults, which should be taken into special consideration
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Aim To evaluate the release of sodium hypochlorite from three different commercial brands of heat-polymerized acrylic resin immersed in water and submitted to mechanical or chemical polishing after disinfection with hypochlorite at different concentrations. Material and methods Fifty-four disk-shaped specimens (n = 18) were made for each resin (Lucitone 550, QC-20, and Classico) and assigned to two groups according to the type of polishing. Specimens were divided in three sub-groups in relation to sodium hypochlorite concentration (1%, 2.5%, and 5.25%), and the groups were immersed for 10-min periods in each sodium hypochlorite concentration. The electrochemical method used for detecting the release of sodium hypochlorite in each specimen was the cyclic voltammetry. Results In the specimens of Clássico resin polished mechanically and immersed in 5.25% sodium hypochlorite, as well as Lucitone and QC-20 resins immersed in 2.5%, the amounts of disinfectant solution released in the four 15-min water exchanges were higher than the four 60-min exchanges. Conclusion There were differences in hypochlorite release from the three commercial brands of denture-base acrylic resins subjected to mechanical polishing. However, no hypochlorite release from the same resins was observed when they were subjected to chemical polishing.
Objetivo Evaluar la liberación de hipoclorito de sodio de 3 marcas comerciales diferentes de resinas termo-polimerizadas sumergidas en agua, y sometidas a pulido mecánico o químico después de la desinfección con hipoclorito a diferentes concentraciones. Material y métodos Cincuenta y cuatro especímenes en forma de disco (n = 18) fueron confeccionados para cada resina (Lucitone 550, QC-20 y Clássico) y asignados a 2 grupos de acuerdo con el tipo de pulido. Las muestras se dividieron en 3 subgrupos en relación con la concentración de hipoclorito de sodio (1, 2,5 y 5,25%), y los grupos se sumergieron durante períodos de 10 min en cada concentración de hipoclorito de sodio. El método electroquímico usado para la detección de la liberación de hipoclorito de sodio en cada espécimen fue a través de voltametría cíclica. Resultados En las muestras pulidas mecánicamente de resina Clássico inmerso en hipoclorito de sodio al 5,25%, así como en las resinas Lucitone y QC-20 inmersas a 2,5%, la cantidad de solución desinfectante liberada en los 4 intercambios de agua de 15 min fue superior a los 4 de 60 min. Conclusión Hubo diferencias en la liberación de hipoclorito de las 3 marcas comerciales de resinas acrílicas sometidas a pulido mecánico. Sin embargo, no se observó liberación de hipoclorito en las mismas resinas cuando se sometieron a pulido químico.
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Humans , Resins, Synthetic , Sodium Hypochlorite/chemistry , Dentures , Dental Disinfectants/chemistry , Time Factors , Acrylic ResinsABSTRACT
to assess the efficiency of cleaning/disinfection of surfaces of an Intensive Care Unit. descriptive-exploratory study with quantitative approach conducted over the course of four weeks. Visual inspection, bioluminescence adenosine triphosphate and microbiological indicators were used to indicate cleanliness/disinfection. Five surfaces (bed rails, bedside tables, infusion pumps, nurses' counter, and medical prescription table) were assessed before and after the use of rubbing alcohol at 70% (w/v), totaling 160 samples for each method. Non-parametric tests were used considering statistically significant differences at p<0.05. after the cleaning/disinfection process, 87.5, 79.4 and 87.5% of the surfaces were considered clean using the visual inspection, bioluminescence adenosine triphosphate and microbiological analyses, respectively. A statistically significant decrease was observed in the disapproval rates after the cleaning process considering the three assessment methods; the visual inspection was the least reliable. the cleaning/disinfection method was efficient in reducing microbial load and organic matter of surfaces, however, these findings require further study to clarify aspects related to the efficiency of friction, its frequency, and whether or not there is association with other inputs to achieve improved results of the cleaning/disinfection process.
avaliar a eficiência da limpeza/desinfecção de superfícies de uma Unidade de Terapia Intensiva. trata-se de estudo descritivo-exploratório com abordagem quantitativa, realizado durante quatro semanas. Utilizaram-se como indicadores para limpeza/desinfecção a avaliação visual, trifosfato de adenosina por bioluminescência e indicador microbiológico. Foram avaliadas, antes e depois da aplicação de álcool a 70% (p/v), cinco superfícies, grade da cama, mesa de cabeceira, bomba de infusão, balcão de enfermagem e mesa de prescrição médica, totalizando 160 amostras para cada método. Utilizaram-se testes não paramétricos, considerando-se diferença estatisticamente significativa para p<0,05. após o processo de limpeza/desinfecção, 87,5, 79,4 e 87,5% das superfícies foram consideradas limpas utilizando os métodos de monitoramento visual, trifosfato de adenosina por bioluminescência e microbiológico, respectivamente. Houve redução estatisticamente significante nas taxas de reprovação após o processo, considerando os três métodos de avaliação. A avaliação visual foi o método menos confiável. o processo de limpeza/desinfecção foi eficiente na redução da carga microbiana e matéria orgânica das superfícies, no entanto, esses achados podem contribuir para estudos adicionais, a fim de elucidar aspectos relacionados à técnica de fricção, sua frequência e associação ou não com outros insumos com o objetivo de alcançar melhores resultados no processo de limpeza/desinfecção.
evaluar la eficiencia de la limpieza/desinfección de superficies de una Unidad de Terapia Intensiva. se trata de estudio descriptivo exploratorio con abordaje cuantitativo, realizado durante cuatro semanas. Se utilizaron como indicadores para limpieza/desinfección la evaluación visual, el trifosfato de adenosina por bioluminiscencia y el indicador microbiológico. Fueron evaluadas, antes y después de la aplicación de alcohol a 70% (p/v), cinco superficies: baranda de la cama, mesa de cabecera, bomba de infusión, mostrador de enfermería y mesa de prescripción médica, totalizando 160 muestras para cada método. Se utilizaron pruebas no paramétricas, considerando como diferencia estadísticamente significativa p<0,05. después del proceso de limpieza/desinfección, 87,5, 79,4 y 87,5% de las superficies fueron consideradas limpias utilizando los métodos de monitorización visual, trifosfato de adenosina por bioluminiscencia y microbiológico, respectivamente. Considerando los tres métodos de evaluación, se constató reducción estadísticamente significativa en las tasas de reprobación después del proceso. La evaluación visual fue el método menos confiable. el proceso de limpieza/desinfección fue eficiente en la reducción de la carga microbiana y materia orgánica de las superficies, sin embargo, esos hallazgos pueden contribuir para realizar estudios adicionales, con el objetivo de elucidar aspectos relacionados a la técnica de fricción, su frecuencia y asociación o no con otros insumos con el objetivo de alcanzar mejores resultados en el proceso de limpieza/desinfección.
Subject(s)
Disinfection/methods , Disinfection/standards , Hospitals , Intensive Care Units , Adenosine Triphosphate/analysis , Methicillin-Resistant Staphylococcus aureus/isolation & purificationABSTRACT
Objective - The aim of this study was to assess by the turbidity method, the presence of microbial contamination in gutta-percha cones used by specialization students. Methods - Forty first series gutta-percha cones were collected and divided into 4 groups of different origins: cones in Group I were collected directly from the sealed package; cones in Group II were collected from the package which had already been open in the clinical environment; cones in Group III from the same origin as Group II but they were disinfected in a 2% sodium hypochlorite; and Group IV were cones collected from the sealed package but manipulated without wearing gloves. The presence or absence of turbidity in the medium was adopted as the evaluation criterion. Results - The results showed that the cones in Group I, II and III presented no contamination and all the cones in Group IV presented microbial growth. The data were analyzed by the Kruskal-Wallis test which showed a level of significance of 1% for the cones in Group IV. Conclusion - It was concluded that the possibility of viable microorganisms existing in gutta-percha cones is minimal, and the use of disinfection methods is justified due to the possible contamination of the cones during incorrect manipulation.
Objetivo - O presente trabalho avaliou a presença de contaminação microbiana, pelo método da turbidez, em cones de guta-percha utilizados por alunos de especialização. Métodos - Foram coletados quarenta cones de guta-percha de primeira série e divididos em 4 grupos de diferentes procedências: Grupo I cones coletados diretamente da embalagem lacrada; Grupo II cones coletados de embalagens que já se encontravam abertas no ambiente clínico; Grupo III cones da mesma procedência do Grupo II, porém desinfetados em solução de hipocloritode sódio 2% e o Grupo IV foram cones coletados da embalagem lacrada, porém manipulados com a mão sem luva. A presença ou ausência de turvação do meio foi adotada como critério de avaliação. Resultados - Os resultados evidenciaram que cones dos Grupos I, II e II não apresentaram contaminação e todos os cones do Grupo IV apresentaram crescimento microbiano. Os dados foram analisados pelo Teste de Kruskal Wallis apresentando nível de significância 1% para os cones do Grupo IV. Conclusão - Concluí-se que a possibilidade de existir microrganismos viáveis em cones de guta-percha é mínima e que a utilização de métodos de desinfecção justificam-se devido a uma possível contaminação dos cones pela manipulação incorreta.
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OBJECTIVE To explore the disinfection methods for slippers that used in operation room. METHODS A total of 120 pairs of slippers were monitored on their disinfection half of them were with automatic washer machine as a test group; while control group was dealed mannally with compound chlorine disinfection solution. The disinfection effects of two groups were compared. RESULTS The disinfection effects of two methods were identical, but had a difference of work efficiency. CONCLUSIONS The slippers used in operating room are contaminated by bacteria seriously. The manual disinfection method is low inefficient. The test group by machine method is with good efficiency and safety, so, it was recommendable for clinical use.
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OBJECTIVE To investigate bacterial contamination of throat spray in different patient groups before and after using it and explore the satisfactory disinfection methods for decreasing the rate of hospital acquired infection.METHODS The methods were used in accordance with Disinfection Technology Criteria.We compared the germicidal effect of five kinds of methods.RESULTS Bacterial contamination was very serious after using throat spray,many bacteria,even pathogens,as well as the normal flora from the region of nasopharynx had been found there.Bacterial contamination was more serious in ENT department patient than in endoscopy patient after using throat sprays.Burning,alcohol,iodophor and disinfectants containing iodine with alcohol were better than oxidized potential water method on disinfection effect.CONCLUSIONS Much attention should be paid to the contamination of throat spray,selecting the most effective disinfection methods,hospital infections caused by invasive manipulation could be prevented when correct methods are adopted.