-
Water Research Jul 2021Due to rising concerns about water pollution and affordability, there is a rapidly-growing public acceptance and global market for a variety of point-of-use (POU)... (Review)
Review
Due to rising concerns about water pollution and affordability, there is a rapidly-growing public acceptance and global market for a variety of point-of-use (POU) devices for domestic uses. However, the efficiencies and mechanisms of POU technologies for removing regulated and emerging disinfection byproducts (DBPs) are still not systematically known. To facilitate the development of this field, we summarized performance trends of four common technologies (i.e., boiling, adsorption, membrane filtration, and advanced oxidation) on mitigating preformed DBPs and identified knowledge gaps. The following highest priority knowledge gaps include: 1) data on DBP levels at the tap or cup in domestic applications; 2) certainty regarding the controls of DBPs by heating processes as DBPs may form and transform simultaneously; 3) standards to evaluate the performance of carbon-based materials on varying types of DBPs; 4) long-term information on the membrane performance in removing DBPs; 5) knowledge of DBPs' susceptibility toward advanced redox processes; 6) tools to monitor/predict the toxicity and diversity of DBPs formed in waters with varying precursors and when implementing different treatment technologies; and 7) social acceptance and regulatory frameworks of incorporating POU as a potential supplement to current centralized-treatment focused DBP control strategies. We conclude by identifying research needs necessary to assure POU systems protect the public against regulated and emerging DBPs.
Topics: Adsorption; Disinfectants; Disinfection; Halogenation; Water; Water Pollutants, Chemical; Water Purification
PubMed: 34091221
DOI: 10.1016/j.watres.2021.117265 -
Journal of the American Association For... Sep 2021Pathogen transmission into zebrafish colonies is controlled through vigilant biosecurity practices. One such practice is embryo surface disinfection, which often uses...
Pathogen transmission into zebrafish colonies is controlled through vigilant biosecurity practices. One such practice is embryo surface disinfection, which often uses sodium hypochlorite. However, if sodium hypochlorite is used at an inappropriate pH, concentration, or exposure time, zebrafish embryos can experience significant mortality and morbidity. Reagent-grade sodium hypochlorite is often used for embryo surface disinfection because commercial-grade sodium hypochlorite has additional ingredients that may have deleterious effects on the embryo. In addition, chlorine dioxide and the combination of sodium chloride and potassium peroxymonosulfate (SCPP) are effective equipment disinfectants; however, the effects of these chemical agents on zebrafish embryos during surface disinfection are unknown. In this study, we exposed strain 5D zebrafish embryos (ages, 6 and 24 h postfertilization) to 4 chlorine-containing agents (reagent-grade sodium hypochlorite [bleach], commercial-grade sodium hypochlorite [bleach], SCPP, and chlorine dioxide) at either 50- or 100- ppm for 5 or 10 min. All groups were evaluated at 5 d postfertilization for survival, hatching rate, and morphologic defect rate. The experimental group with the highest survival and hatching rates and the lowest morphologic defect rate was the 24-h postfertilization embryos exposed to 50 ppm SCPP for 5 min. The survival, hatching rate, and defect rate did not differ significantly among age-matched controls; however, the hatching rate after exposure to 50 ppm SCPP was significantly higher than that of embryos exposed to 50 ppm reagent-grade sodium hypochlorite for 5 min (100% compared with 23% respectively). SCPP solution may provide an alternative surface disinfectant for zebrafish embryos because it maximizes survival and hatching rates and minimizes morphologic defect rates. However, in vivo efficacy against common zebrafish pathogens requires further testing. Use of chlorine dioxide at 50 ppm or greater is not recommended for zebrafish embryo surface disinfection due to significant mortality among 6 and 24 h postfertilization embryos.
Topics: Animals; Chlorine; Disinfectants; Disinfection; Sodium Hypochlorite; Zebrafish
PubMed: 34416927
DOI: 10.30802/AALAS-JAALAS-20-000164 -
International Journal of Environmental... Nov 2019Healthcare-associated infections (HAIs) can be caused by microorganisms present in common practice instruments generating major health problems in the hospital...
Healthcare-associated infections (HAIs) can be caused by microorganisms present in common practice instruments generating major health problems in the hospital environment. The aim of this work was to evaluate the disinfection capacity of a portable ultraviolet C equipment (UV Sanitizer Corvent -UVSC-) developed to disinfect different objects. For this purpose, six pathogens causing HAIs: , , , , and , were inoculated on slides and discs of different biomaterials (borosilicate, polycarbonate, polyurethane, silicone, Teflon and titanium) and exposed to ultraviolet C radiation. UVSC disinfection was compared with ethanol and chlorhexidine antimicrobial activities following the standards EN14561 and EN14562. Disinfection, established as a reduction of five logarithms from the initial inoculum, was achieved with the UVSC at 120 s of exposure time, with and without the presence of organic matter. The disinfectant effect was observed against , , , and (reduction >99.999%). Disinfection was also achieved with 70% ethanol and 2% chlorhexidine. As conclusion, UVSC was effective disinfecting the most contaminated surfaces assayed, being a promising alternative for disinfecting hospital materials and inanimate objects that cannot be immersed in liquid biocides, reducing the risk of pathogen transmission.
Topics: Biofilms; Cross Infection; Disinfectants; Disinfection; Equipment Contamination; Ultraviolet Rays
PubMed: 31783593
DOI: 10.3390/ijerph16234747 -
Biocontrol Science 2021Control of infectious diseases requires switching from usual hygiene such as water wiping and cleaning, to control measures including appropriate and aggressive...
Control of infectious diseases requires switching from usual hygiene such as water wiping and cleaning, to control measures including appropriate and aggressive disinfection using 70% alcohol and/or hypochlorous acid depending on the pathogen. Nevertheless, some nursery schools might not understand or select proper disinfectant methods. A survey was administered by the local government of Ibaraki prefecture, Japan in January 2018 to all 456 nursery schools in Ibaraki prefecture. The surveyed items were the number of nursery teachers, usual manual hygiene among children, usual disinfection for lavatories, diaper changing spaces, tables used by children for meals, and classroom floors when there was no vomiting in the facilities and no outbreak in surrounding area. Moreover, it asked about disinfection procedures if children vomited during a community outbreak of gastroenteritis infection. We defined proper use for usual disinfection of a lavatory or diaper changing space as chlorine-based disinfectant including hypochlorous acid or 70% alcohol according to guidelines. Overall, 403 nursery schools responded to the survey. All nursery schools implemented usual hand hygiene. Association between proper disinfection and the size of nursery schools was not significant. Moreover, association between proper disinfection and nursery schools with nurse presence was not found to be significant.
Topics: Child; Disinfectants; Disinfection; Humans; Hypochlorous Acid; Japan; Schools, Nursery
PubMed: 33716247
DOI: 10.4265/bio.26.37 -
Viruses Sep 2022Nipah virus is a relatively newly discovered emerging virus on the WHO list of priority pathogens which has the potential to cause outbreaks with high fatality rates....
Nipah virus is a relatively newly discovered emerging virus on the WHO list of priority pathogens which has the potential to cause outbreaks with high fatality rates. Whilst progress is being made in the development of animal models for evaluating vaccines and therapies, some of the more fundamental data on Nipah virus are lacking. We performed studies to generate novel information on the aerosol survival of Nipah virus and to look at the efficacy of two common disinfectants. We also performed studies to evaluate the inactivation of Nipah virus by using neutral buffered formalin. Nipah virus was relatively stable in a small particle (1-5 µm) aerosol in the dark, with it having a decay rate of 1.46%min. Sodium hypochlorite (at 10%) and ethanol (at 80%) reduced the titre of Nipah virus to undetectable levels. Nipah virus that was in tissue culture medium was also inactivated after 24 h in the presence of 10% formalin.
Topics: Aerosols; Animals; Disinfectants; Disinfection; Ethanol; Formaldehyde; Henipavirus Infections; Nipah Virus; Sodium Hypochlorite; Virus Inactivation
PubMed: 36146863
DOI: 10.3390/v14092057 -
Revue Scientifique Et Technique... Mar 1995Testing under laboratory conditions is undoubtedly useful in assessing the activity of disinfectants. However, such testing must be regarded as no more than a... (Review)
Review
Testing under laboratory conditions is undoubtedly useful in assessing the activity of disinfectants. However, such testing must be regarded as no more than a preliminary to field trials. This not only indicates the unreliability of laboratory tests, but also poses the wider problem of how any laboratory evaluation can be correlated with the field requirements. Many attempts have therefore been made to devise tests which are suitable to evaluate the in-use requirements of disinfection (e.g. on farms). The aim of these techniques is to record the end-point of a disinfection procedure on the surfaces in animal houses. In view of the need to standardise testing conditions in the field, the author provides details of the optimum time and place for taking samples under field conditions. Samples for culture media should be taken from the floor when dry. The various techniques (i.e. swabbing, agar cylinder, agar carrier, 'ready-to-use' set) should provide information on the end-point of the disinfection. The desired end-points is approximately one viable bacterium per cm2 of surface area. The technique used should demonstrate whether the disinfection has been effective.
Topics: Animals; Bacteria; Disinfectants; Disinfection; Housing, Animal; Microbial Sensitivity Tests
PubMed: 7548973
DOI: No ID Found -
HERD Jan 2021The purpose of this study was to evaluate environmental surface materials used in healthcare environments for material composition, methicillin-resistant (MRSA)...
OBJECTIVE
The purpose of this study was to evaluate environmental surface materials used in healthcare environments for material composition, methicillin-resistant (MRSA) viability, and a comparison of two disinfectants, a bleach germicidal cleaner and Decon7, a novel disinfectant.
BACKGROUND
Contaminated environmental surfaces have been associated with outbreaks of healthcare-associated illness (HAIs). One in every 20 patients in U.S. acute care hospitals acquire a healthcare-associated illness, leading to consequences such as elevated morbidity, mortality, and a decrease in quality of life. In the patient environment, MRSA can remain viable from hours to up to 14 days.
METHODS
Environmental surface materials were evaluated as new and worn. Material composition and properties were assessed to evaluate surface integrity and the influence on the disinfection of MRSA. Inoculated materials were used to assess MRSA viability over time and the efficacy of a manufacturer's recommended cleaning and disinfection product compared to a novel disinfectant.
RESULTS
Environmental surface materials respond differently in appearance and roughness, when mechanically worn. When measuring MRSA survival, at 24 hr, MRSA colony forming unit (CFU) counts were reduced on the copper sheet surface and solid surface with cupric oxide. By 72 hr, all MRSA counts were zero. Bleach and the novel disinfectant were equally effective at disinfecting MRSA from all surface types.
CONCLUSIONS
This study highlights a gap in knowledge about the impact of type and wear of environmental surface materials used in healthcare environments on contamination with epidemiologically important organisms. In conclusion, environmental surface material wear, properties, and cleaning and disinfection efficacy are important factors to consider when addressing HAIs.
Topics: Disinfectants; Disinfection; Hospitals; Humans; Methicillin-Resistant Staphylococcus aureus; Quality of Life
PubMed: 32867539
DOI: 10.1177/1937586720952892 -
Applied and Environmental Microbiology Sep 2021Opportunistic pathogens can linger on surfaces in hospital and building plumbing environments, leading to infections in at-risk populations. Furthermore,...
Opportunistic pathogens can linger on surfaces in hospital and building plumbing environments, leading to infections in at-risk populations. Furthermore, biofilm-associated bacteria are protected from removal and inactivation protocols such as disinfection. Bacteriophages show promise as tools to treat antibiotic-resistant infections. As such, phages may also be useful in environmental applications to prevent newly acquired infections. In the current study, the potential of synergies between bacteriophage and chemical disinfection against the opportunistic pathogen Pseudomonas aeruginosa was assessed under various conditions. Specifically, surface-associated P. aeruginosa was treated with various concentrations of phages (P1 or JG004), chemical disinfectants (sodium hypochlorite or benzalkonium chloride), or combined sequential treatments under three distinct attachment models (spot inoculations, dry biofilms, and wet biofilms). Phages were very effective at removing bacteria in spot inoculations (>3.2 log removal) and wet biofilms (up to 2.6 log removal), while phages prevented the regrowth of dry biofilms in the application time. In addition, phage treatment followed by chemical disinfection inactivated P. aeruginosa cells under wet biofilm conditions better than either treatment alone. This effect was hindered when chemical disinfection was applied first, followed by phage treatment, suggesting that the additive benefits of combination treatments are lost when phage is applied last. Furthermore, we confirm previous evidence of greater phage tolerance to benzalkonium chloride than to sodium hypochlorite, informing choices for combination phage-disinfectant approaches. Overall, this paper further supports the potential of using combination phage and chemical disinfectant treatments to improve the inactivation of surface-associated P. aeruginosa. Phages are already utilized in the health care industry to treat antibiotic-resistant infections, such as those on implant-associated biofilms and in compassionate-care cases. Phage treatment could also be a promising new tool to control pathogens in the built environment, preventing infections from occurring. This study shows that phages can be combined effectively with chemical disinfectants to improve the removal of wet biofilms and bacteria spotted onto surfaces while preventing regrowth in dry biofilms. This has the potential to improve pathogen containment within the built environment and drinking water infrastructure to prevent infections by opportunistic pathogens.
Topics: Bacteriophages; Benzalkonium Compounds; Biofilms; Disinfectants; Disinfection; Plastics; Pseudomonas aeruginosa; Sodium Hypochlorite
PubMed: 34347517
DOI: 10.1128/AEM.00980-21 -
Environmental Health Perspectives Nov 1986A test system for water distribution was used to evaluate the stability and effectiveness of three residual disinfectants--free chlorine, combined chlorine, and chlorine...
A test system for water distribution was used to evaluate the stability and effectiveness of three residual disinfectants--free chlorine, combined chlorine, and chlorine dioxide--when challenged with a sewage contaminant. The test distribution system consisted of the street main and internal plumbing for two barracks at Fort George G. Meade, MD. To the existing pipe network, 152 m (500 ft) of 13-mm (0.5 in.) copper pipe were added for sampling, and 60 m (200 ft) of 2.54-cm (1.0 in.) plastic pipe were added for circulation. The levels of residual disinfectants tested were 0.2 mg/L and 1.0 mg/L as available chlorine. In the absence of a disinfectant residual, microorganisms in the sewage contaminant were consistently recovered at high levels. The presence of any disinfectant residual reduced the microorganism level and frequency of occurrence at the consumer's tap. Free chlorine was the most effective residual disinfectant and may serve as a marker or flag in the distribution network. Free chlorine and chlorine dioxide were the least stable in the pipe network. The loss of disinfectant in the pipe network followed first-order kinetics. The half-life determined in static tests for free chlorine, chlorine dioxide, and combined chlorine was 140, 93, and 1680 min.
Topics: Bacteriophages; Chlorine; Disinfectants; Disinfection; Drug Stability; Enterobacteriaceae; Evaluation Studies as Topic; Poliovirus; Water Microbiology; Water Supply
PubMed: 3028767
DOI: 10.1289/ehp.866915 -
Biocontrol Science 2021The current pandemic of novel coronavirus disease (COVID-19) has highlighted the importance of disinfectants. As a raw material for next-generation disinfectants,... (Review)
Review
The current pandemic of novel coronavirus disease (COVID-19) has highlighted the importance of disinfectants. As a raw material for next-generation disinfectants, scallop shell-derived calcium oxide (CaO) has been revealed to exhibit significant virucidal and microbicidal activities and is compatible with living tissues and the environment. This minireview summarizes recent progress in the development of disinfectants from scallop shell-CaO, focusing especially on studies of clinical and daily use applications. We describe the preparation, basic characteristics, and virucidal and microbicidal activities of scallop shell-CaO disinfectants. Furthermore, their applications in the disinfection of contaminated masks and the treatment of infected wounds are briefly introduced.
Topics: Animal Shells; Animals; Calcium Compounds; Disinfectants; Disinfection; Humans; Oxides; Pectinidae
PubMed: 34556615
DOI: 10.4265/bio.26.129