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Physiological Reports Jun 2020Ozone is a toxic and highly reactive gaseous oxidizing chemical with well-documented adverse health effects in humans. On the basis of animal and human data,...
Ozone is a toxic and highly reactive gaseous oxidizing chemical with well-documented adverse health effects in humans. On the basis of animal and human data, environmental guidelines and air quality standards recommend a threshold for exposure of no more than 0.063 ppm of ozone (daily concentrations). This research describes a standardized sensitive model of sterile murine lung inflammation induced by exposing mice to acute (0, 4 or 24 hr), yet low, levels of ozone (0.005, 0.05 or 0.5 ppm), one that are below the current recommendations for what is considered a safe or "ambient" ozone concentration for humans. Ozone led to concentration and time-dependent phlogistic cell death in the bronchoalveolar lavage, lung epithelial damage and hemorrhage. Interestingly, we observed distinct large bright CD11b positive cells in the bronchoalveolar lavage, upregulation of lung vascular and alveolar ATP synthase as well as plasminogen and bronchiolar angiostatin expression in ozone-exposed mice, platelet and neutrophil accumulation in the lung vasculature and an eotaxin-2, IL-16, CXCL5, CXCL12, and CXCL13 dominant inflammatory response leading to lung injury. Using a fluorescent intravital microscopy set up, we quantified ozone-induced extensive alveolar cellular damage. We observed ozone-induced actin filament disorganization, perturbed respiratory mechanics, acute suppression of the alveolar reactive oxygen species (ROS) production and mitochondrial potential in ventilated lungs. We present evidence of systemic, as well as pulmonary toxicity, at 40-fold lower ozone concentrations than previously reported in mice. The findings are important in establishing a sensitive means of quantifying structural and functional lung disorganization following exposure to an aerosolized pollutant, even at levels of ozone exposure previously thought to be safe in humans.
Topics: Acute Lung Injury; Animals; Inflammation Mediators; Male; Mice, Inbred C57BL; Ozone; Pneumonia
PubMed: 32524776
DOI: 10.14814/phy2.14463 -
Infection and Drug Resistance 2022To examine the bactericidal effects of three different states of medical ozone (liquid, gas, and oil) against drug-resistant strains of common bacteria on burn wounds,...
OBJECTIVE
To examine the bactericidal effects of three different states of medical ozone (liquid, gas, and oil) against drug-resistant strains of common bacteria on burn wounds, which could as a clinical reference.
METHODS
Three multidrug-resistant strains of methicillin-resistant , pan-resistant , and ESBLs were identified from burn wounds. The colonies of the three varieties of bacteria were each carried out using the pour plate method prior to the start of the experiment. Then, depending on the state of ozone, different treatment procedures are applied. Group of ozone gas: in a closed glass jar, the bacterial liquid was injected into a single layer of sterile gauze, and the ozone gas concentration was held at 50 g/mL. The bacterial liquid was diluted and combined directly with ozone water in the ozone water group. Ozone is a type of oil: after the emulsifier was added to the oil group. The gas, water, and oil groups were rapidly neutralized and counted again after 5, 10, and 30 minutes.
RESULTS
Ozone gas and oil groups totally eliminated multidrug resistant bacteria in the above study within 30 minutes. (2) At 5 and 10 minutes, the difference in bactericidal effect between ozone gas group and ozone water and oil group was statistically significant (P<0.05), and there was no significant difference between ozone water and oil groups (P>0.05); at the time of 30 minutes, the effects of bactericidal effect between ozone water group and ozone gas and oil had no significance (P> 0.05).
CONCLUSION
Ozone has the ability to kill bacteria, depending on the treatment time, different ozone types should be chosen for sterilization and disinfection in clinical application.
PubMed: 35418764
DOI: 10.2147/IDR.S353277 -
Chemosphere Jun 2023Microplastics (MPs) are substances that pose a risk to both human life and the environment. Their types and production are increasing year on year, and their potential...
Microplastics (MPs) are substances that pose a risk to both human life and the environment. Their types and production are increasing year on year, and their potential to cause environmental pollution is a worldwide concern. Conventional water treatment processes, particularly coagulation and sedimentation, are not effective at removing all MPs. It is therefore important to assess the morphological changes in the MPs, i.e., the thermoplastic polyurethane (TPU) and polyethylene (PE), during ozonation and the dissolved organic carbon leaching as well as chloroform formation in the subsequent chlorination. The results show that the appearance and surface chemistry of the MPs changed during the ozonation process, most notably for TPU. The trichloromethane (CHCl) generation during chlorination was 0.168 and 0.152 μmol/L for TPU and PE, respectively, and the ozone pretreatment significantly increased the CHCl yield of TPU, while it had a weak effect on PE. Additional disinfection byproducts (DBPs), including CHClBr, CHClBr, and CHBr, were produced in the presence of bromide ions in the water column, and the total amount of DBPs produced by PE, PE-O, TPU, and TPU-O was significantly increased to 0.787, 0.814, 0.931, and 1.391 μmol/L, respectively. The study provides useful information for the environmental risk assessment of two representative MPs, i.e., TPU and MPs, in disinfection procedures for drinking water.
Topics: Humans; Disinfection; Microplastics; Plastics; Halogenation; Water Purification; Chloroform; Polyurethanes; Ozone; Water Pollutants, Chemical; Disinfectants
PubMed: 36963574
DOI: 10.1016/j.chemosphere.2023.138488 -
Medycyna Pracy Feb 2021The outbreak of coronavirus disease 2019 (COVID-19) generated a huge pressure on health care systems worldwide and exposed their lack of preparation for a major health... (Review)
Review
The outbreak of coronavirus disease 2019 (COVID-19) generated a huge pressure on health care systems worldwide and exposed their lack of preparation for a major health crisis. In the times of a respiratory disease pandemic, members of the dental profession, due to having a direct contact with the patients' oral cavity, body fluids and airborne pathogens, are exposed to a great occupational hazard of becoming infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The authors carried out a systematic literature search using the main online databases (PubMed, Google Scholar, MEDLINE, UpToDate, Embase, and Web of Science) with the following keywords: "COVID-19," "2019-nCoV," "coronavirus," "SARS-CoV-2," "dental COVID-19," "dentistry COVID-19," "occupational hazards dentistry," "ventilation," "air disinfection," "airborne transmission," "hydrogen peroxide disinfection," "UV disinfection," "ozone disinfection," "plasma disinfection," and "TiO disinfection." They included publications focused on COVID-19 features, occupational hazards for dental staff during COVID-19 pandemic, and methods of air disinfection. They found that due to the work environment conditions, if appropriate measures of infection control are not being implemented, dental offices and dental staff can become a dangerous source of COVID-19 transmission. That is why the work safety protocols in dentistry have to be revised and additional methods of decontamination implemented. The authors specifically advise on the utilization of wildly accepted methods like ultraviolet germicidal irradiation with additional disinfection systems, which have not been introduced in dentistry yet, like vaporized hydrogen peroxide, non-thermal plasma and air filters with photocatalytic disinfection properties. Due to its toxicity, ozone is not the first-choice method for air decontamination of enclosed clinical settings. Med Pr. 2021;72(1):39-48.
Topics: Air; COVID-19; Dental Offices; Disinfection; Humans; Infection Control; Pandemics
PubMed: 33063773
DOI: 10.13075/mp.5893.01005 -
Water Research Sep 2019The wide application of chlorine disinfectant for drinking water treatment has led to the appearance of chlorine-resistant bacteria, which pose a severe threat to public...
The wide application of chlorine disinfectant for drinking water treatment has led to the appearance of chlorine-resistant bacteria, which pose a severe threat to public health. This study was performed to explore the physiological-biochemical characteristics and environmental influence (pH, temperature, and turbidity) of seven strains of chlorine-resistant bacteria isolated from drinking water. Ozone disinfection was used to investigate the inactivation effect of bacteria and spores. The DNA concentration and cell surface structure variations of typical chlorine-resistant spores (Bacillus cereus spores) were also analysed by real-time qPCR, flow cytometry, and scanning electron microscopy to determine their inactivation mechanisms. The ozone resistance of bacteria (Aeromonas jandaei < Vogesella perlucida < Pelomonas < Bacillus cereus < Aeromonas sobria) was lower than that of spores (Bacillus alvei < Lysinibacillus fusiformis < Bacillus cereus) at an ozone concentration of 1.5 mg/L. More than 99.9% of Bacillus cereus spores were inactivated by increasing ozone concentration and treatment duration. Moreover, the DNA content of Bacillus cereus spores decreased sharply, but approximately 1/4 of the target genes remained. The spore structure exhibited shrinkage and folding after ozone treatment. Both cell structures and gene fragments were damaged by ozone disinfection. These results showed that ozone disinfection is a promising method for inactivating chlorine-resistant bacteria and spores in drinking water.
Topics: Chlorine; Disinfectants; Disinfection; Drinking Water; Ozone; Spores, Bacterial; Water Purification
PubMed: 31158616
DOI: 10.1016/j.watres.2019.05.014 -
Ultrasonics Sonochemistry Aug 2021Reduction of sanitizer dosage and development of non-immersion disinfection methods have become major focuses of research. Here, we examined the disinfection efficacy of...
Reduction of sanitizer dosage and development of non-immersion disinfection methods have become major focuses of research. Here, we examined the disinfection efficacy of combining gaseous ozone (4 and 8 ppm) with aerosolized oxidizing sanitizer [sodium hypochlorite (SH, 100 and 200 ppm)] and aerosolized organic acid [acetic acid (AA, 1% and 2%) and lactic acid (LA, 1% and 2%)]. Notably, 1% AA and 4 ppm gaseous ozone were ineffective for disinfecting Salmonella Typhimurium, and treatment with 1% AA + 8 ppm ozone caused browning of lettuce leaves and stimulated increases in aerobic mesophilic count (AMC), aerobic psychrotrophic count (APC), S. Typhimurium, and Escherichia coli O157:H7. Treatment with 2% LA + 8 ppm ozone resulted in the lowest S. Typhimurium, E. coli O157:H7, Listeria monocytogenes, AMC, APC, and molds and yeasts during storage (0-7 days at 4 °C). Quality analysis indicates that LA + 8 ppm ozone and SH + 8 ppm ozone did not negatively affect L*, a*, b*, polyphenolic content, weight loss, and sensory properties; however, the levels of two individual phenolic compounds (3,4-dihydroxybenzoic acid and vanillin), responsible for phenylpropanoid synthesis, were significantly increased after treatment with 2% LA + 8 ppm ozone. These findings provided insights into the use of LA combined with gaseous ozone for application in disinfecting fresh produce.
Topics: Aerosols; Disinfection; Food Microbiology; Lactuca; Ozone; Polyphenols; Taste; Ultrasonic Waves
PubMed: 34126525
DOI: 10.1016/j.ultsonch.2021.105622 -
Cureus Sep 2021Personal protective equipment (PPE) is urgently sought during public health crises. It is necessary for the safety of both the patient and the healthcare professional....
OBJECTIVE
Personal protective equipment (PPE) is urgently sought during public health crises. It is necessary for the safety of both the patient and the healthcare professional. Yet during the recent COVID-19 pandemic, PPE scarcity in many countries, including the United States, has impacted the level of care for patients and the safety of healthcare personnel. Additionally, the implementation of mandatory mask mandates for the general public in many countries forced individuals to either reuse PPE, which can contribute to poor hygiene, or buy PPE in bulk and thereby contribute to the scarcity of PPE. In this study, we investigate the possibility of using a cost-effective ozone sterilization unit on contaminated N95 masks as an alternative to current sterilization methods.
METHOD
This protocol examined ozone's ability to decontaminate N95 mask fabric that was exposed to a surrogate virus (). Once the sterilization unit achieves an ozone concentration of ~30 ppm, a 60-minute or 120-minute sterilization cycle commences. Following the sterilization cycle, we investigated the amount of viable virus on the slide using a viral plaque assay and compared it to a non-sterilized, control slide. Furthermore, we carried out trials to investigate the safety of an ozone sterilization device, by measuring the levels of ozone exposure that individuals may experience when operating the sterilization unit post-cycle.
RESULTS
We showed that a 120-minute sterilization cycle at ~30 ppm achieves a 3-log reduction in viral activity, thereby complying with industry and U.S. Food and Drug Administration (FDA) standards. Further, we demonstrated that when following our protocol, the ozone exposure levels for a simple sterilization unit to be used at home complied with federal and industry standards.
CONCLUSION
Ozone may have the potential to decontaminate masks and other PPE.
PubMed: 34722033
DOI: 10.7759/cureus.18228 -
Environmental Pollution (Barking, Essex... Dec 2020Disinfection means the killing of pathogenic organisms (e.g. bacteria and its spores, viruses, protozoa and their cysts, worms, and larvae) present in water to make it... (Review)
Review
Disinfection means the killing of pathogenic organisms (e.g. bacteria and its spores, viruses, protozoa and their cysts, worms, and larvae) present in water to make it potable for other domestic works. The substances used in the disinfection of water are known as disinfectants. At municipal level, chlorine (Cl), chloramines (NHCl, NHCl), chlorine dioxide (ClO), ozone (O) and ultraviolet (UV) radiations, are the most commonly used disinfectants. Chlorination, because of its removal efficiency and cost effectiveness, has been widely used as method of disinfection of water. But, disinfection process may add several kinds of disinfection by-products (DBPs) (∼600-700 in numbers) in the treated water such as Trihalomethanes (THM), Haloacetic acids (HAA) etc. which are detrimental to the human beings in terms of cytotoxicity, mutagenicity, teratogenicity and carcinogenicity. In water, THMs and HAAs were observed in the range from 0.138 to 458 μg/L and 0.16-136 μg/L, respectively. Thus, several regulations have been specified by world authorities like WHO, USEPA and Bureau of Indian Standard to protect human health. Some techniques have also been developed to remove the DBPs as well as their precursors from the water. The popular techniques of DBPs removals are adsorption, advance oxidation process, coagulation, membrane based filtration, combined approaches etc. The efficiency of adsorption technique was found up to 90% for DBP removal from the water.
Topics: Chlorine; Disinfectants; Disinfection; Drinking Water; Halogenation; Trihalomethanes; Water Pollutants, Chemical; Water Purification
PubMed: 32889516
DOI: 10.1016/j.envpol.2020.115474 -
International Journal of Molecular... Sep 2023The results of a comprehensive study of the patterns of structural and functional changes in bone tissue samples after combined (ozone + radiation) sterilization are...
The results of a comprehensive study of the patterns of structural and functional changes in bone tissue samples after combined (ozone + radiation) sterilization are presented. The study used a different approach to the sterilization process with selective ozone or radiation exposure and an integral, combined one, based on a combined ozone-oxygen treatment of bone samples at the first stage and radiation at the second. The methods of IR spectroscopy, scanning electron microscopy with a prefix for elemental analysis, atomic force microscopy, and mechanical analysis with determination of elastic-plastic properties (Vickers microhardness index) were used in the work. It is shown that the ozone exposure used at the first stage of the combined sterilization process of bone implants does not lead to negative consequences with respect to their properties and characteristics. The results obtained serve as a scientific and methodological basis for the further improvement and optimization of sterilization technologies (including combined). They also offer a comprehensive justification of the parameters of sterilization regimes to ensure the safety of using bone implants during reconstructive operations, minimizing structural and functional changes in bone matter, and creating effective health-saving technologies and the possibility of using them for various biomedical applications.
Topics: Sterilization; Prostheses and Implants; Ozone; Technology; Bone and Bones
PubMed: 37833874
DOI: 10.3390/ijms241914426 -
Water Research Sep 2021Odors and tastes have become universal problems related to drinking water quality. In addition to the typical odor problems caused by algae or microorganisms, the... (Review)
Review
Odors and tastes have become universal problems related to drinking water quality. In addition to the typical odor problems caused by algae or microorganisms, the occurrence of odors derived from drinking water disinfection have attracted attention. The chlor(am)ination-derived odor substances have certain toxicity and odor-causing characteristics, and would enter the tap water through water distribution systems, directly affecting drinking water safety and customer experience. This study provided a comprehensive overview of the occurrence, detection, and control of odor substances derived from drinking water chlor(am)ination disinfection. The occurrence and formation mechanisms of several typical types of disinfection derived odor substances were summarized, including haloanisoles, N-chloroaldimines, iodotrihalomethanes, and halophenoles. They are mainly derived from specific precursors such as halophenols, anisoles, and amino acids species during the disinfection or distribution networks. In addition, the change of disinfectant during chlor(am)ination was also one of the causes of disinfection odors. Due to the extremely low odor threshold concentrations (OTCs) of these odor substances, the effective sample pre-enrichment for instrument identification and quantification are essential. The control strategies of odor problems mainly include adsorption, chemical oxidation, and combined processes such as ozonation and biological activated carbon processes (O/BAC) and ultraviolet-based advanced oxidation processes (UV-AOPs). Finally, the challenges and possible future research directions in this research field were discussed and proposed.
Topics: Disinfectants; Disinfection; Halogenation; Odorants; Water Pollutants, Chemical; Water Purification
PubMed: 34419919
DOI: 10.1016/j.watres.2021.117549