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International Journal of Molecular... Mar 2022Flame retardants have attracted growing environmental concern. Recently, an increasing number of studies have been conducted worldwide to investigate flame-retardant...
Photocatalytic Degradation of 4,4'-Isopropylidenebis(2,6-dibromophenol) on Magnetite Catalysts vs. Ozonolysis Method: Process Efficiency and Toxicity Assessment of Disinfection By-Products.
Flame retardants have attracted growing environmental concern. Recently, an increasing number of studies have been conducted worldwide to investigate flame-retardant sources, environmental distribution, living organisms' exposure, and toxicity. The presented studies include the degradation of 4,4'-isopropylidenebis(2,6-dibromophenol) (TBBPA) by ozonolysis and photocatalysis. In the photocatalytic process, nano- and micro-magnetite (n-FeO and μ-FeO) are used as a catalyst. Monitoring of TBBPA decay in the photocatalysis and ozonolysis showed photocatalysis to be more effective. Significant removal of TBBPA was achieved within 10 min in photocatalysis ( 90%), while for ozonation, a comparable effect was observed within 70 min. To determine the best method of TBBPA degradation concentration on COD and TOC, the removals were examined. The highest oxidation state was obtained for photocatalysis on μ-FeO, whereas for n-FeO and ozonolysis, the COD/TOC ratio was lower. Acute toxicity results show noticeable differences in the toxicity of TBBPA and its degradation products to and . The EC values indicate that TBBPA degradation products were toxic to harmful, whereas the TBPPA and post-reaction mixtures were toxic to the invertebrate species tested. The best efficiency in the removal and degradation of TBBPA was in the photocatalysis process on μ-FeO (reaction system 1). The examined crustaceans can be used as a sensitive test for acute toxicity evaluation.
Topics: Disinfection; Ferrosoferric Oxide; Flame Retardants; Ozone; Phenols; Polybrominated Biphenyls
PubMed: 35408795
DOI: 10.3390/ijms23073438 -
Journal of the American Association For... May 2022Most in vivo animal research and breeding using mice and rats in China takes place in facilities under barrier conditions. Items being moved across the barrier are...
Most in vivo animal research and breeding using mice and rats in China takes place in facilities under barrier conditions. Items being moved across the barrier are typically disinfected using UV radiation in a transfer hatch. However, the time periods necessary for this disinfection technique are inefficient, and disinfection is frequently incomplete, especially if concealed surfaces are present. The current study used a newly developed transfer hatch incorporating both UV and ozone disinfection to examine disinfection efficacy against 4 bacteria species ( and ). Disinfection trials used UV and ozone, applied separately and in combination, for up to 30 min. Separate and combined treatments were also tested with a UV barrier. We found that if UV radiation has direct contact with surfaces, it is an efficient disinfection method. However, where surfaces are concealed by a UV barrier, UV radiation performs relatively poorly. The results of this study indicate that a combination of UV and ozone produces the most effective disinfection and is markedly quicker than current disinfection times for UV applied on its own. This novel transfer hatch design therefore allows more complete and efficient disinfection, improves workflow, and reduces barrier breaches by pathogens that may affect animal health and welfare and compromise research outcomes.
Topics: Animals; Bacteria; Disinfectants; Disinfection; Mice; Ozone; Rats; Ultraviolet Rays
PubMed: 35393007
DOI: 10.30802/AALAS-JAALAS-21-000131 -
Water Research Jun 2022Cethyltrimethylammonium chloride (CTMA) is one of the most used quaternary ammonium compounds (QACs) in consumer products. CTMA and other QACs are only partially...
Cethyltrimethylammonium chloride (CTMA) is one of the most used quaternary ammonium compounds (QACs) in consumer products. CTMA and other QACs are only partially eliminated in municipal wastewater treatment and they can interact with bacteria in biological processes. Currently, there is only limited information on the antimicrobial efficiency of CTMA in matrices other than standard growth media and if and how CTMA influences conventional chemical disinfection. The results obtained in this study showed that the susceptibility of E. coli to CTMA was significantly enhanced in phosphate-buffered saline, lake water and wastewater compared to broth. In broth, a minimum inhibitory concentration (MIC) of CTMA of 20 mgL was observed for E. coli, whereas a 4-log inactivation occurred for CTMA concentrations of about 4 mgL in buffered ultra-purified water, a lake water and wastewater effluent. The impacts of the pre-exposure and the presence of CTMA on inactivation by ozone and monochloramine were tested with three different E. coli strains: AG100 with the efflux pump acrAB intact, AG100A with it deleted and AG100tet with it overexpressed. Pre-exposure of E. coli AG100 to CTMA led to an increased susceptibility for ozone with second-order inactivation rate constants (∼ 10 Ms) increasing by a factor of about 1.5. An opposite trend was observed for monochloramine with second-order inactivation rate constants (∼ 10 Ms) decreasing by a factor of about 2. For E. coli AG100tet, the second-order inactivation rate constant decreased by a factor of almost 2 and increased by a factor of about 1.5 for ozone and monochloramine, respectively, relative to the strain AG100. The simultaneous presence of CTMA and ozone enhanced the second-order inactivation rate constants for CTMA concentrations of 2.5 mgL by a factor of about 3. For monochloramine also an enhancement of the inactivation was observed, which was at least additive but might also be synergistic. Enhancement by factors from about 2 to 4.5 were observed for CTMA concentrations > 2.5 mgL.
Topics: Bis-Trimethylammonium Compounds; Cetrimonium; Chloramines; Disinfection; Escherichia coli; Kinetics; Ozone; Wastewater; Water; Water Purification
PubMed: 35366494
DOI: 10.1016/j.watres.2022.118278 -
BMC Infectious Diseases Mar 2022Ozone (O) is an effective disinfectant agent that leaves no harmful residues. Due to the global health crisis caused by the COVID-19 pandemic, surgical masks are in high...
BACKGROUND
Ozone (O) is an effective disinfectant agent that leaves no harmful residues. Due to the global health crisis caused by the COVID-19 pandemic, surgical masks are in high demand, with some needing to be reused in certain regions. This study aims to evaluate the effects of O for pathogen disinfection on reused surgical masks in various conditions.
METHODS
O generators, a modified PZ 2-4 for Air (2000 mg O/L) and a modified PZ 7 -2HO for Air (500 mg O/L), were used together with 1.063 m (0.68 × 0.68 × 2.3 m) and 0.456 m (0.68 × 0.68 × 1.15 m) acrylic boxes as well as a room-sized 56 m (4 × 4 × 3.5 m) box to provide 3 conditions for the disinfection of masks contaminated with enveloped RNA virus (10 FFU/mL), bacteria (10 CFU/mL) and fungi (10 spores/mL).
RESULTS
The virucidal effects were 82.99% and 81.70% after 15 min of treatment with 2000 mg/L O at 1.063 m and 500 mg/L O at 0.456 m, respectively. The viral killing effect was increased over time and reached more than 95% after 2 h of incubation in both conditions. By using 2000 mg/L O in a 1.063 m box, the growth of bacteria and fungi was found to be completely inhibited on surgical masks after 30 min and 2 h of treatment, respectively. Using a lower-dose O generator at 500 mg O/L in 0.456 m provided lower efficiency, although the difference was not significant. Using O at 2000 mg O/L or 500 mg O/L in a 56 m room is efficient for the disinfection of all pathogens on the surface of reused surgical masks.
CONCLUSIONS
This study provided the conditions for using O (500-2000 mg/L) to reduce pathogens and disinfect contaminated surgical masks, which might be applied to reduce the inappropriate usage of reused surgical masks.
Topics: COVID-19; Disinfection; Humans; Ozone; Pandemics; SARS-CoV-2
PubMed: 35255835
DOI: 10.1186/s12879-022-07227-3 -
Molecules (Basel, Switzerland) Feb 2022This study evaluated the pasteurization (P), ozone (O), ultrasonic (US), and high-hydrostatic-pressure (HHP) sterilization approaches for processing of regarding...
This study evaluated the pasteurization (P), ozone (O), ultrasonic (US), and high-hydrostatic-pressure (HHP) sterilization approaches for processing of regarding browning factors and microorganisms, compared with non-sterilization (control check, CK) treatment. The microorganisms (total bacterial count and fungi and yeast count) in the juice were identified after different sterilization techniques, while the quality parameter changes (degree of browning, color measurements, total phenolic content, reducing sugar, ascorbic acid, 5-hydroxymethyl furaldehyde (5-HMF), amino acid nitrogen, total soluble solids (TSS), pH value) were investigated. The results indicate that P and HHP treatment reduced non-enzymatic browning while substantially impacting the color measurements, TSS, and pH, while the sterilization effect was remarkable, with a rate exceeding 90%. Furthermore, the juices treated with P and HHP sterilization were used as the objects, and the CK group was used as the control group. They were placed at 4 °C, 25 °C and 37 °C, respectively, and stored in dark for 15 d. Sampling and determination were carried out on 0, 3, 6, 9, 12, and 15 d, respectively. M-&-Y (molds and yeasts) were not detected in the late storage period, and no obvious microbial growth was observed during storage, indicating that P and HHP treatments could ensure the microbial safety of juice. P- and HHP- treated juice has better quality and low temperature storage is beneficial for maintaining the quality of juice. Therefore, P treatment or HHP treatment combined with low temperature storage could achieve a more ideal storage effect. Overall, this study conclusively established that P and HHP methods were suitable for sterilizing juice. These techniques minimally affected overall product quality while better maintaining the quality parameters than the untreated juice samples and those exposed to O and US treatment.
Topics: Food Microbiology; Food Preservation; Fruit and Vegetable Juices; Prunus; Sterilization
PubMed: 35208989
DOI: 10.3390/molecules27041197 -
Chirurgie (Heidelberg, Germany) Jun 2022Surgery as an important part of the healthcare sector contributes to environmental pollution and therefore to the climate crisis. The aim of this review is to create an... (Review)
Review
BACKGROUND
Surgery as an important part of the healthcare sector contributes to environmental pollution and therefore to the climate crisis. The aim of this review is to create an overview of the current data situation and possibilities for improvement.
METHODS
A literature search was performed in PubMed/MEDLINE using the following five terms: "carbon footprint and surgery", "climate change and surgery", "waste and surgery" and "greening the operating room" focusing on energy, waste, water and anesthesia.
RESULTS
The greatest part of emissions in surgery is generated by the use of energy. The operating rooms (OR) need 3-6 times more energy than the other hospital rooms. Of the total hospital waste 20-30% is produced during operations, which is particularly due to the increasing use of disposable articles and 50-90% of waste classified as hazardous is incorrectly sorted. The disposal of this waste is not only more environmentally harmful but also much more expensive. The processing of surgical items by autoclaving consumes large amounts of water. Modern sterilization methods, for example using plasma could be future alternatives. Up to 20% of volatile nonmetabolized anesthetic agents are vented into the stratosphere and destroy the ozone layer. Intravenous anesthetic drugs should be used whenever possible instead. The choice of operating method can also contribute to the environmental impact of an operation.
CONCLUSION
The surgical disciplines are a relevant producer of environmental pollutants. Through diverse interdisciplinary approaches surgery can also contribute to protecting the environment.
Topics: Carbon Footprint; Climate Change; Global Warming; Operating Rooms; Water
PubMed: 35138418
DOI: 10.1007/s00104-021-01551-1 -
Forensic Science International Apr 2022While good laboratory practice in a forensic lab minimises the chance of infection of laboratory personnel, in certain cases, possible contamination of pieces of...
While good laboratory practice in a forensic lab minimises the chance of infection of laboratory personnel, in certain cases, possible contamination of pieces of evidence with highly contagious pathogens might call for additional precautions. The number of potential disinfection methods that might be suitable for forensic genetics are surprisingly limited. First and foremost, the ideal technique should not inhibit DNA amplification, it should be effective against a host of pathogens, and it should be applicable on porous surfaces. We examined ozone treatment on extracted DNA samples and mock casework samples. Ozone-treated and control specimens were amplified with Qiagen Investigator ESSplex SE QS kit. Detected allele counts were compared between the treated and untreated sample groups. Following disinfection, concentration of ozone-treated DNA was about half of the control samples, but full STR profiles were recovered. In the case of mock casework samples (disposable surgical masks), there was no significant difference (p = 0.513) between the detected allele counts of control and ozone-treated samples. Sampling location of surgical masks (earloop, nosepiece) showed a statistically significant difference (p = 0.011), though. Comparing the effect of contributors on STR profiling, a significant difference (p = 0.001) was observed, which could be explained with the differences between individuals including shedding capacity, head size or shape. According to our pilot study, ozone treatment does not encumber the routine forensic DNA analysis, the sampling position or the contributor affected the allele counts more than the ozone treatment.
Topics: DNA Fingerprinting; Disinfection; Humans; Microsatellite Repeats; Ozone; Pilot Projects
PubMed: 35131730
DOI: 10.1016/j.forsciint.2022.111212 -
Journal of Microbiological Methods Mar 2022Ozone treatment is an eco-friendly and cost-effective approach to achieve material disinfection, and this disinfection method is of utmost importance in the present...
Ozone treatment is an eco-friendly and cost-effective approach to achieve material disinfection, and this disinfection method is of utmost importance in the present global pandemic. The efficacy of ozone's oxidative potential on common microorganisms has been extensively studied, particularly in the food and water treatment industries. However, little is still understood regarding its antimicrobial capabilities for the treatment of textile substrates in air. In this study, fabric swatches inoculated with bacterial and fungal suspensions are exposed to ozone for different durations and at different ozone concentrations. Pathogenic bacteria (Escherichia coli, Staphylococcus aureus), and fungi (Aspergillus fumigatus, and Candida albicans), are the microbes utilised in this study. The efficacy of ozone is demonstrated by the complete removal of microbiota on the tested swatches when a concentration and exposure duration of 20 ppm and 4 mins are respectively maintained in a test ozone chamber. We expect the insights from this work to guide the development of new ozonation techniques capable of rapid sterilisation in industrial & public settings.
Topics: Bacteria; Disinfection; Escherichia coli; Ozone; Water Purification
PubMed: 35131364
DOI: 10.1016/j.mimet.2022.106431 -
Ultrasonics Sonochemistry Feb 2022In minimal processing industry, chlorine is widely used in the disinfection process and ultrasound (US) increases the disinfection efficacy of chlorine and reduces the...
In minimal processing industry, chlorine is widely used in the disinfection process and ultrasound (US) increases the disinfection efficacy of chlorine and reduces the cross-contamination incidence during washing. Tap water (TW), which has no disinfection effect, is generally used to rinse off sanitizer residues on the surface of disinfected fresh-cut vegetables. In this study, aqueous ozone (AO), a low-cost and residue-free sanitizer, was used to replace TW rinsing in combination with US (28 kHz)-chlorine (free chlorine [FC] at 10 ppm, a concentration recommended for industrial use) for the disinfection of fresh-cut lettuce as a model. US-chlorine (40 s) + 2.0 ppm AO (60 s) treatment resulted in browning spots on lettuce surface at the end of storage. In contrast, US-chlorine (40 s) + 1.0 ppm AO (60 s) did not lead to deterioration of the sensory quality (sensory crispness, color, and flavor) and a change in total color difference, and the activities of browning-related enzymes were significantly lower. Moreover, US-chlorine (40 s) + 1.0 ppm of AO (60 s) treatment led to significantly lower counts of Escherichia coli O157:H7, Salmonella Typhimurium, aerobic mesophilic (AMC), and molds and yeasts (M&Y) on days 0-7 than US-chlorine (60 s) + TW (60 s) and single 1.0 ppm AO (120 s) treatments, suggesting that AO provided an additional disinfection effect over TW, while reducing the overall processing time by 20 s. Cell membrane permeability analysis (alkaline phosphatase, protein, nucleotide, and adenosine triphosphate leakage) showed that the combination with 1.0 ppm AO caused more severe cell membrane damage in E. coli O157:H7 and S. Typhimurium, explaining the higher disinfection efficacy. 16S rRNA sequencing revealed that following US-chlorine (40 s) + 1.0 ppm of AO (60 s) treatment, Massilia and Acinetobacter had higher relative abundances (RAs) on day 7 than after US-chlorine (60 s) + TW (60 s) treatment, whereas the RAs of Escherichia-Shigella was significantly lower, indicating that the former treatment has a superior capacity in maintaining a stable microbial composition. This explains from an ecological point of view why US-chlorine (40 s) + 1.0 ppm of AO (60 s) led to the lowest AMC and M&Y counts during storage. The study results provide evidence that AO has potential as an alternative to TW rinsing to increase the disinfection efficacy of US-chlorine.
Topics: Colony Count, Microbial; Disinfectants; Disinfection; Escherichia coli O157; Food Contamination; Food Handling; Food Microbiology; Ozone; RNA, Ribosomal, 16S; Water
PubMed: 35092941
DOI: 10.1016/j.ultsonch.2022.105931 -
Brazilian Oral Research 2022The aim of this scoping review was to provide sufficient information about the effectiveness of ozone gas in virus inactivation of surfaces and objects under different... (Review)
Review
The aim of this scoping review was to provide sufficient information about the effectiveness of ozone gas in virus inactivation of surfaces and objects under different environmental conditions. The review was performed according to the list of PRISMA SrC recommendations and the JBI Manual for Evidence Synthesis for Scoping Reviews. The review was registered in Open Science Framework (OSF). EMBASE (Ovid), Lilacs, LIVIVO, MEDLINE (PubMed), SciELO, Scopus and Web of Science were primary sources, and "gray literature" was searched in OpenGray and OpenThesis. A study was included if it reported primary data on the effect of ozone gas application for vehicle-borne and airborne virus inactivation. No language or publication date restriction was applied. The search was conduct on July 1, 2020. A total of 16,120 studies were screened, and after exclusion of noneligible studies, fifteen studies fulfilled all selection criteria. Application of ozone gas varied in terms of concentration, ozone exposure period and the devices used to generate ozone gas. Twelve studies showed positive results for inactivation of different virus types, including bacteriophages, SARS-CoV-2 surrogates and other vehicle-borne viruses. Most of the studies were classified as unclear regarding sponsorship status. Although most of the population has not yet been vaccinated against COVID-19, disinfection of environments, surfaces, and objects is an essential prevention strategy to control the spread of this disease. The results of this Scoping Review demonstrate that ozone gas is promising for viral disinfection of surfaces.
Topics: COVID-19; Delivery of Health Care; Disinfection; Humans; Ozone; SARS-CoV-2
PubMed: 35081224
DOI: 10.1590/1807-3107bor-2022.vol36.0006