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Tropical Biomedicine Mar 2024Water pollution in developing countries continues to be a major health problem due to various anthropological activities that contribute to the spread of many parasitic...
Water pollution in developing countries continues to be a major health problem due to various anthropological activities that contribute to the spread of many parasitic diseases, including those caused by helminths. The aim of this study is to explore the ability of ozone and peroxone to disinfect drinking water contaminated samples with Toxocara canis eggs. The oxidants used were ozone and ozone-hydrogen peroxide combination. The treatment of Toxocara canis eggs was carried out in a 50 ml reactor with an operating volume of 10 ml. The pH conditions (5, 7 and 10) were varied for each treatment. The treatment effect was calculated by counting eggs and examining the condition of the larvae larval condition (whole, broken and hatched larvae) using an optical microscope. The experiment was carried out by exposing the eggs for 60 and 120 minutes to ozone and peroxone. The best results were obtained for helminths treated with the ozone/hydrogen peroxide combination at pH 10, with an inactivation of 79.2%. The synergistic effect of ozone combined with hydrogen peroxide allows higher helminth egg inactivation rates, demonstrating that advanced oxidation processes are a real alternative to apply in the inactivation of Toxocara canis eggs. The results obtained in this study show that the ozone and peroxone treatment could be a useful disinfection process to destroy or inactivate Toxocara canis eggs in processes commonly applied in water treatment.
Topics: Animals; Ozone; Toxocara canis; Disinfection; Disinfectants; Hydrogen-Ion Concentration; Hydrogen Peroxide; Ovum; Water Purification; Peroxides; Larva; Drinking Water
PubMed: 38852133
DOI: 10.47665/tb.41.1.006 -
Journal of Environmental Sciences... Oct 2024As a strong oxidizing agent, ozone is used in some water treatment facilities for disinfection, taste and odor control, and removal of organic micropollutants....
As a strong oxidizing agent, ozone is used in some water treatment facilities for disinfection, taste and odor control, and removal of organic micropollutants. Phenylalanine (Phe) was used as the target amino acid to comprehensively investigate variability of disinfection byproducts (DBPs) formation during chlorine disinfection and residual chlorine conditions subsequent to ozonation. The results showed that subsequent to ozonation, the typical regulated and unregulated DBPs formation potential (DBPsFP), including trichloromethane (TCM), dichloroacetonitrile (DCAN), chloral hydrate (CH), dichloroacetic acid (DCAA), trichloroacetic acid (TCAA), and trichloroacetamide (TCAcAm) increased substantially, by 2.4, 3.3, 5.6, 1.2, 2.5, and 6.0 times, respectively, compared with only chlorination. Ozonation also significantly increased the DBPs yield under a 2 day simulated residual chlorine condition that mimicked the water distribution system. DBPs formations followed pseudo first order kinetics. The formation rates of DBPs in the first 6 hr were higher for TCM (0.214 hr), DCAN (0.244 hr), CH (0.105 hr), TCAcAm (0.234 hr), DCAA (0.375 hr) and TCAA (0.190 hr) than thereafter. The peak DBPsFP of TCM, DCAN, CH, TCAcAm, DCAA, and TCAA were obtained when that ozonation time was set at 5-15 min. Ozonation times > 30 min increased the mineralization of Phe and decreased the formation of DBPs upon chlorination. Increasing bromine ion (Br) concentration increased production of bromine- DBPs and decreased chlorine-DBPs formation by 59.3%-92.2% . Higher ozone dosages and slight alkaline favored to reduce DBP formation and cytotoxicity. The ozonation conditions should be optimized for all application purposes including DBPs reduction.
Topics: Ozone; Halogenation; Disinfection; Water Purification; Water Pollutants, Chemical; Phenylalanine; Disinfectants; Chlorine
PubMed: 38802231
DOI: 10.1016/j.jes.2023.08.030 -
Chemosphere Aug 2024Research has demonstrated the presence of viruses in wastewater (WW), which can remain viable for a long period, posing potential health risks. Conventional WW treatment...
Research has demonstrated the presence of viruses in wastewater (WW), which can remain viable for a long period, posing potential health risks. Conventional WW treatment methods involving UV light, chlorine and ozone efficiently reduce microbial concentrations, however, they produce hazardous byproducts and microbial resistance that are detrimental to human health and the ecosystem. Hence, there is a need for novel disinfection techniques. Antimicrobial Photodynamic Inactivation (PDI) emerges as a promising strategy, utilizing photosensitizers (PS), light, and dioxygen to inactivate viruses. This study aims to assess the efficacy of PDI by testing methylene blue (MB) and the cationic porphyrin TMPyP as PSs, along a low energy consuming white light source (LED) at an irradiance of 50 mW/cm, for the inactivation of bacteriophage Phi6. Phi6 serves as an enveloped RNA-viruses surrogate model in WW. PDI experiments were conducted in a buffer solution (PBS) and real WW matrices (filtered and non-filtered). Considering the environmental release of the treated effluents, this research also evaluated the ecotoxicity of the resulting solution (post-PDI treatment effluent) on the model organism Daphnia magna, following the Organisation for Economic Cooperation and Development (OECD) immobilization technical 202 guideline. Daphnids were exposed to WW containing the tested PS at different concentrations and dilutions (accounting for the dilution factor during WW release into receiving waters) over 48 h. The results indicate that PDI with MB efficiently inactivated the model virus in the different aqueous matrices, achieving reductions superior to 8 log PFU/mL, after treatments of 5 min in PBS and of ca. 90 min in WW. Daphnids survival increased when subjected to the PDI-treated WW with MB, considering the dilution factor. Overall, the effectiveness of PDI in eliminating viruses in WW, the fading of the toxic effects on daphnids after MB' irradiation and the rapid dilution effect upon WW release in the environment highlight the possibility of using MB in WW PDI-disinfection.
Topics: Wastewater; Disinfection; Daphnia; Photosensitizing Agents; Animals; Methylene Blue; Porphyrins; Bacteriophages; Waste Disposal, Fluid; Water Purification; Ecotoxicology
PubMed: 38797202
DOI: 10.1016/j.chemosphere.2024.142421 -
Sensors (Basel, Switzerland) May 2024The traditional aviary decontamination process involves farmers applying pesticides to the aviary's ground. These agricultural defenses are easily dispersed in the air,...
The traditional aviary decontamination process involves farmers applying pesticides to the aviary's ground. These agricultural defenses are easily dispersed in the air, making the farmers susceptible to chronic diseases related to recurrent exposure. Industry 5.0 raises new pillars of research and innovation in transitioning to more sustainable, human-centric, and resilient companies. Based on these concepts, this paper presents a new aviary decontamination process that uses IoT and a robotic platform coupled with ozonizer (O) and ultraviolet light (UVL). These clean technologies can successfully decontaminate poultry farms against pathogenic microorganisms, insects, and mites. Also, they can degrade toxic compounds used to control living organisms. This new decontamination process uses physicochemical information from the poultry litter through sensors installed in the environment, which allows accurate and safe disinfection. Different experimental tests were conducted to construct the system. First, tests related to measuring soil moisture, temperature, and pH were carried out, establishing the range of use and the confidence interval of the measurements. The robot's navigation uses a back-and-forth motion that parallels the aviary's longest side because it reduces the number of turns, reducing energy consumption. This task becomes more accessible because of the aviaries' standardized geometry. Furthermore, the prototype was tested in a real aviary to confirm the innovation, safety, and effectiveness of the proposal. Tests have shown that the UV + ozone combination is sufficient to disinfect this environment.
Topics: Animals; Robotics; Poultry; Ultraviolet Rays; Chickens; Decontamination; Disinfection; Ozone; Internet of Things
PubMed: 38793903
DOI: 10.3390/s24103049 -
Environmental Pollution (Barking, Essex... Aug 2024While sodium hypochlorite (NaClO) has long been used to disinfect drinking water, concerns have risen over its use due to causing potentially hazardous byproducts....
Assessment of microorganisms in drinking water disinfected by catalytic ozonation with fluorinated ceramic honeycomb and NaClO disinfectants under laboratory and pilot conditions.
While sodium hypochlorite (NaClO) has long been used to disinfect drinking water, concerns have risen over its use due to causing potentially hazardous byproducts. Catalytic ozonation with metal-free catalysts has attracted increasing attention to eliminate the risk of secondary pollution of byproducts in water treatment. Here, we compared the disinfection efficiency and microbial community of catalytic ozone with a type of metal-free catalyst fluorinated ceramic honeycomb (FCH) and NaClO disinfectants under laboratory- and pilot-scale conditions. Under laboratory conditions, the disinfection rate of catalytic ozonation was 3∼6-fold that of ozone when the concentration of Escherichia coli was 1 × 10 CFU/ml, and all E. coli were killed within 15 s. However, 0.65 mg/L NaClO retained E. coli after 30 min using the traditional culturable approach. The microorganism inactivation results of raw reservoir water disinfected by catalytic ozonation and ozonation within 15 s were incomparable based on the cultural method. In pilot-scale testing, catalytic ozonation inactivated all environmental bacteria within 4 min, while 0.65 mg/L NaClO could not achieve this success. Both catalytic ozonation and NaClO-disinfected methods significantly reduced the number of microorganisms but did not change the relative abundances of different species, i.e., bacteria, viruses, eukaryotes, and archaea, based on metagenomic analyses. The abundance of virulence factors (VFs) and antimicrobial resistance genes (ARGs) was detected few in catalytic ozonation, as determined by metagenomic sequencing. Some VFs or ARGs, such as virulence gene 'FAS-II' which was hosted by Mycobacterium_tuberculosis, were detected solely by the NaClO-disinfected method. The enriched genes and pathways of cataO-disinfected methods exhibited an opposite trend, especially in human disease, compared with NaClO disinfection. These results indicated that the disinfection effect of catalytic ozone is superior to NaClO, this finding contributed to the large-scale application of catalytic ozonation with FCH in practical water treatment.
Topics: Ozone; Disinfectants; Drinking Water; Disinfection; Ceramics; Water Purification; Sodium Hypochlorite; Catalysis; Halogenation; Escherichia coli; Pilot Projects; Water Microbiology; Bacteria
PubMed: 38782162
DOI: 10.1016/j.envpol.2024.124184 -
Water Research Jun 2024While online monitoring of physicochemical parameters has widely been incorporated into drinking water treatment systems, online microbial monitoring has lagged behind,...
While online monitoring of physicochemical parameters has widely been incorporated into drinking water treatment systems, online microbial monitoring has lagged behind, resulting in the use of surrogate parameters (disinfectant residual, applied dose, concentration × time, CT) to assess disinfection system performance. Online flow cytometry (online FCM) allows for automated quantification of total and intact microbial cells. This study sought to investigate the feasibility of online FCM for full-scale drinking water ozone disinfection system performance monitoring. A water treatment plant with high lime solids turbidity in the ozone contactor influent was selected to evaluate the online FCM in challenging conditions. Total and intact cell counts were monitored for 40 days and compared to surrogate parameters (ozone residual, ozone dose, and CT) and grab sample assay results for cellular adenosine triphosphate (cATP), heterotrophic plate counts (HPC), impedance flow cytometry, and 16S rRNA gene sequencing. Online FCM provided insight into the dynamics of the full-scale ozone system, including offering early warning of increased contactor effluent cell concentrations, which was not observed using surrogate measures. Positive correlations were observed between online FCM intact cell counts and cATP levels (Kendall's tau=0.40), HPC (Kendall's tau=0.20), and impedance flow cytometry results (Kendall's tau=0.30). Though a strong correlation between log intact cell removal and CT was not observed, 16S rRNA gene sequencing results showed that passage through the ozone contactor significantly changed the microbial community (p < 0.05). Potential causes of the low overall cell inactivation in the contactor and the significant changes in the microbial community after ozonation include regrowth in the later chambers of the contactor and varied ozone resistance of drinking water microorganisms. This study demonstrates the suitability of direct, online microbial analysis for monitoring full-scale disinfection systems.
Topics: Ozone; Flow Cytometry; Disinfection; Drinking Water; Water Purification
PubMed: 38749337
DOI: 10.1016/j.watres.2024.121702 -
Water Research Jun 2024Water disinfection is undoubtedly regarded as a critical step in ensuring the water safety for human consumption, and ozone is widely used as a highly effective...
Water disinfection is undoubtedly regarded as a critical step in ensuring the water safety for human consumption, and ozone is widely used as a highly effective disinfectant for the control of pathogenic microorganisms in water. Although the diminished ozone efficiencies in complex water matrices have been widely reported, the specific extent to which individual components of matrix act on the virus inactivation by ozone remains unclear, and effective methodologies to predict the comprehensive effects of various factors are needed. In this study, the decoupled impact of the intricate water matrix on the ozone inactivation of viruses was systematically investigated and assessed from a simulative perspective. The concept of "equivalent ozone depletion rate constant" (k') was introduced to quantify the influence of different species, and a kinetic model was developed based on the k' values for simulating the ozone inactivation processes in complex matrix. The mechanisms through which diverse species influenced the ozone inactivation effectiveness were identified: 1) competition effects (k' = 10∼10 Ms), including organic matters and reductive ions (SO, NO, and I), which were the most influential species inhibiting the virus inactivation; 2) shielding effects (k' = 10∼10 Ms), including Ca, Mg, and kaolin; 3) insignificant effects (k' = 0∼1 Ms), including Cl, SO, NO, NH, and Br; 4) promotion effects (k' = ∼-10 Ms), including CO and HCO. Prediction of ozone disinfection efficiency and evaluation of species contribution under complex aquatic matrices were successfully realized utilizing the model. The systematic understanding and methodologies developed in this research provide a reliable framework for predicting ozone inactivation efficiency under complex matrix, and a potential tool for accurate disinfectant dosage determination and interfering factors control in actual wastewater treatment processes.
Topics: Ozone; Wastewater; Virus Inactivation; Disinfection; Water Purification; Disinfectants; Models, Theoretical; Kinetics
PubMed: 38728774
DOI: 10.1016/j.watres.2024.121685 -
Heliyon May 2024This review aims to examine the existence of . nd their antibiotic resistance genes (ARGs) in aquatic settings and the alternative treatment ways. in a various aquatic... (Review)
Review
This review aims to examine the existence of . nd their antibiotic resistance genes (ARGs) in aquatic settings and the alternative treatment ways. in a various aquatic environment have been identified as contaminants with impacts on human health and the environment. resistance to multiple antibiotics, such as sulfamethoxazole, ciprofloxacin, quinolone, trimethoprim, tetracycline, vancomycin, as well as specific antibiotic resistance genes including The development of resistance can occur naturally, through mutations, or via horizontal gene transfer facilitated by sterilizing agents. In addition, an overview of the current knowledge on inactivation of and ARG and the mechanisms of action of various disinfection processes in water and wastewater (UV chlorine processes, catalytic oxidation, Fenton reaction, and ozonation) is given. An overview of the effects of nanotechnology and the resulting wetlands is also given.
PubMed: 38694026
DOI: 10.1016/j.heliyon.2024.e29798 -
Cureus Mar 2024For endodontic therapy to be successful, the root canal space must be sterilized. This is often done using intracanal irrigants and medications. To accomplish...
For endodontic therapy to be successful, the root canal space must be sterilized. This is often done using intracanal irrigants and medications. To accomplish periradicular region sterilization and healing, various intracanal medicaments and irrigation techniques have been researched for better treatment outcomes. Ozonated olive oil is the most researched and successful adjunct to other medicaments owing to its antibacterial properties. Triple antibiotic paste (TAP) (metronidazole, ciprofloxacin, and minocycline) was incorporated as an inter-appointment intracanal dressing. Currently, many newer advances are depicting synergistic effects in the elimination of persistent endodontic pathogens. Given this, in the current case series, periapical lesions were managed non-surgically for alternating weeks by the advent of triple antibiotic paste (TAP) and ozonated olive oil (O-oil) with laser activation. Irrigation and its effects were further enhanced with the use of a laser, aiming for thorough debridement and rendering the canal free of microbes. Once the patient was asymptomatic and there was no sinus drainage seen, final obturation was done. Therefore, this case series depicts that traditional root canal therapy with the use of ozonated olive oil and laser activation can non-surgically heal the lesion, leading to successful treatment outcomes. Periapical lesions in three cases have been observed; on the initial visit, all lesions were accessible, cleansed, and shaped. We administered ozonated olive oil with laser activation and a triple antibiotic paste on the following visit. In all three cases, six-month follow-ups have shown evidence of a successful course of therapy.
PubMed: 38690465
DOI: 10.7759/cureus.57314 -
Environmental Science & Technology May 2024In response to the COVID-19 pandemic, air cleaning technologies were promoted as useful tools for disinfecting public spaces and combating airborne pathogen...
In response to the COVID-19 pandemic, air cleaning technologies were promoted as useful tools for disinfecting public spaces and combating airborne pathogen transmission. However, no standard method exists to assess the potentially harmful byproduct formation from air cleaners. Through a consensus standard development process, a draft standard test method to assess portable air cleaner performance was developed, and a suite of air cleaners employing seven different technologies was tested. The test method quantifies not only the removal efficiency of a challenge chemical suite and ultrafine particulate matter but also byproduct formation. Clean air delivery rates (CADRs) are used to quantify the chemical and particle removal efficiencies, and an emission rate framework is used to quantify the formation of formaldehyde, ozone, and other volatile organic compounds. We find that the tested photocatalytic oxidation and germicidal ultraviolet light (GUV) technologies produced the highest levels of aldehyde byproducts having emission rates of 202 and 243 μg h, respectively. Additionally, GUV using two different wavelengths, 222 and 254 nm, both produced ultrafine particulate matter.
Topics: COVID-19; Volatile Organic Compounds; Particulate Matter; Ozone; Formaldehyde; SARS-CoV-2; Disinfection; Air Pollutants; Ultraviolet Rays; Humans
PubMed: 38683040
DOI: 10.1021/acs.est.3c09331