-
Water Research Apr 2024The presence of biofilms in drinking water distribution systems (DWDS) is responsible for water quality deterioration and a possible source of public health risks.... (Review)
Review
The presence of biofilms in drinking water distribution systems (DWDS) is responsible for water quality deterioration and a possible source of public health risks. Different factors impact the biological stability of drinking water (DW) in the distribution networks, such as the presence and concentration of nutrients, water temperature, pipe material composition, hydrodynamic conditions, and levels of disinfectant residual. This review aimed to evaluate the current state of knowledge on strategies for DW biofilm disinfection through a qualitative and quantitative analysis of the literature published over the last decade. A systematic review method was performed on the 562 journal articles identified through database searching on Web of Science and Scopus, with 85 studies selected for detailed analysis. A variety of disinfectants were identified for DW biofilm control such as chlorine, chloramine, UV irradiation, hydrogen peroxide, chlorine dioxide, ozone, and others at a lower frequency, namely, electrolyzed water, bacteriophages, silver ions, and nanoparticles. The disinfectants can impact the microbial communities within biofilms, reduce the number of culturable cells and biofilm biomass, as well as interfere with the biofilm matrix components. The maintenance of an effective residual concentration in the water guarantees long-term prevention of biofilm formation and improves the inactivation of detached biofilm-associated opportunistic pathogens. Additionally, strategies based on multi-barrier processes by optimization of primary and secondary disinfection combined with other water treatment methods improve the control of opportunistic pathogens, reduce the chlorine-tolerance of biofilm-embedded cells, as well as decrease the corrosion rate in metal-based pipelines. Most of the studies used benchtop laboratory devices for biofilm research. Even though these devices mimic the conditions found in real DWDS, future investigations on strategies for DW biofilm control should include the validity of the promising strategies against biofilms formed in real DW networks.
Topics: Disinfection; Drinking Water; Water Supply; Chlorine; Disinfectants; Water Purification; Biofilms; Chlorides
PubMed: 38359597
DOI: 10.1016/j.watres.2024.121273 -
Frontiers in Endocrinology 2024Smog is a form of extreme air pollution which comprises of gases such as ozone, sulfur dioxide, nitrogen and carbon oxides, and solid particles including particulate... (Review)
Review
Smog is a form of extreme air pollution which comprises of gases such as ozone, sulfur dioxide, nitrogen and carbon oxides, and solid particles including particulate matter (PM and PM). Different types of smog include acidic, photochemical, and Polish. Smog and its constituents are hazardaous to human, animals, and plants. Smog leads to plethora of morbidities such as cancer, endocrine disruption, and respiratory and cardiovascular disorders. Smog components alter the activity of various hormones including thyroid, pituitary, gonads and adrenal hormones by altering regulatory genes, oxidation status and the hypothalamus-pituitary axis. Furthermore, these toxicants are responsible for the development of metabolic disorders, teratogenicity, insulin resistance, infertility, and carcinogenicity of endocrine glands. Avoiding fossil fuel, using renewable sources of energy, and limiting gaseous discharge from industries can be helpful to avoid endocrine disruption and other toxicities of smog. This review focuses on the toxic implications of smog and its constituents on endocrine system, their toxicodynamics and preventive measures to avoid hazardous health effects.
Topics: Humans; Smog; Particulate Matter; Air Pollution; Thyroid Gland; Hormones
PubMed: 38352708
DOI: 10.3389/fendo.2024.1294205 -
Water Research Mar 2024Water reuse is a growing global reality. In regulating water reuse, viruses have come to the fore as key pathogens due to high shedding rates, low infectious doses, and... (Meta-Analysis)
Meta-Analysis Review
Water reuse is a growing global reality. In regulating water reuse, viruses have come to the fore as key pathogens due to high shedding rates, low infectious doses, and resilience to traditional wastewater treatments. To demonstrate the high log reductions required by emerging water reuse regulations, cost and practicality necessitate surrogates for viruses for use as challenge organisms in unit process evaluation and monitoring. Bacteriophage surrogates that are mitigated to the same or lesser extent than viruses of concern are routinely used for individual unit process testing. However, the behavior of these surrogates over a multi-barrier treatment train typical of water reuse has not been well-established. Toward this aim, we performed a meta-analysis of log reductions of common bacteriophage surrogates for five treatment processes typical of water reuse treatment trains: advanced oxidation processes, chlorination, membrane filtration, ozonation, and ultraviolet (UV) disinfection. Robust linear regression was applied to identify a range of doses consistent with a given log reduction of bacteriophages and viruses of concern for each treatment process. The results were used to determine relative conservatism of surrogates. We found that no one bacteriophage was a representative or conservative surrogate for viruses of concern across all multi-barrier treatments (encompassing multiple mechanisms of virus mitigation). Rather, a suite of bacteriophage surrogates provides both a representative range of inactivation and information about the effectiveness of individual processes within a treatment train. Based on the abundance of available data and diversity of virus treatability using these five key water reuse treatment processes, bacteriophages MS2, phiX174, and Qbeta were recommended as a core suite of surrogates for virus challenge testing.
Topics: Bacteriophages; Water; Bacteriophage phi X 174; Water Purification; Disinfection; Levivirus
PubMed: 38342066
DOI: 10.1016/j.watres.2024.121242 -
Environmental Science. Processes &... May 2024The control of viruses in water is critical to preventing the spread of infectious viral diseases. Many oxidants can inactivate viruses, and this study aims to...
The control of viruses in water is critical to preventing the spread of infectious viral diseases. Many oxidants can inactivate viruses, and this study aims to systematically compare the disinfection effects of ozone (O), peroxymonosulfate (PMS), and hydrogen peroxide (HO) on MS2 coliphage. The effects of oxidant dose and contact time on disinfection were explored, as were the disinfection effects of three oxidizing agents in secondary effluent. The 4-log inactivation of MS2 coliphage required 0.05 mM O, 0.5 mM PMS, or 25 mM HO with a contact time of 30 min. All three oxidants achieved at least 4-log disinfection within 30 min, and O required only 0.5 min. In secondary effluent, all three oxidants also achieved 4-log inactivation of MS2 coliphage. Excitation-emission matrix (EEM) results indicate that all three oxidants removed dissolved organic matter synchronously and O oxidized dissolved organic matter more thoroughly while maintaining disinfection efficacy. Considering the criteria of oxidant dose, contact time, and disinfection efficacy in secondary effluent, O is the best choice for MS2 coliphage disinfection among the three oxidants.
Topics: Ozone; Hydrogen Peroxide; Disinfection; Levivirus; Peroxides; Water Purification; Water Microbiology; Disinfectants; Oxidants
PubMed: 38323647
DOI: 10.1039/d3em00527e -
Chemosphere Mar 2024Algal blooms worldwide pose many challenges to drinking water production. Pre-oxidation with NaClO, KMnO, or ozone is commonly used to enhance algal removal in...
Algal blooms worldwide pose many challenges to drinking water production. Pre-oxidation with NaClO, KMnO, or ozone is commonly used to enhance algal removal in conventional drinking water treatment processes. However, these currently utilized oxidation methods often result in significant algal cell lysis or impede the operation of the subsequent units. Higher algal removal with pre-chlorination in algal solutions prepared with natural water, compared to those prepared with ultrapure water, has been observed. In the present studies, preliminary findings indicate that ammonium in natural water alters chlorine species to NHCl, leading to improved treatment efficiency. NHCl with 1.5-3.0 mg∙L as Cl with an oxidation time of 3-7 h significantly enhancing algal removal by coagulation. The selective oxidation of surface-absorbed organic matter (S-AOM) by NHCl, followed by the subsequent peeling off of this material from the algal surface, leading to an increase in zeta potential from -20.2 mV to -3.8 mV, constitutes the primary mechanism of enhanced algal removal through coagulation. These peeled S-AOM retained their large molecular weight and acted as polymer aids. Compared with NaClO and KMnO, NHCl displays the best performance in improving algal removal, avoiding cell lysis, and decreasing the potential for nitrogenous disinfection byproducts formation under the reaction conditions used in this study. Notably, in major Chinese cities, water purification plants commonly rely on suburban lakes or reservoirs as water sources, necessitating the transportation of raw water over long distances for times up to several hours. These conditions favor the implementation of NHCl pre-oxidation. The collective results indicate the potential of NHCl oxidation as a viable pretreatment strategy for algal contamination during water treatment processes.
Topics: Drinking Water; Chloramines; Disinfection; Chlorine; Halogenation; Water Purification; Water Pollutants, Chemical
PubMed: 38311043
DOI: 10.1016/j.chemosphere.2024.141312 -
Journal of the Science of Food and... May 2024In order to explore the effect of ozone sterilization treatment on tomato disease control and increase fruit setting rate, this study took 906 pink fruit tomato as test...
BACKGROUND
In order to explore the effect of ozone sterilization treatment on tomato disease control and increase fruit setting rate, this study took 906 pink fruit tomato as test material, used a small ozone generator to carry out ozone treatment single-factor test, and then selected orthogonal table to guide the ozone treatment combination. The effects of different ozone treatment concentration, ozone treatment duration and ozone treatment times on the growth, disease and fruit setting rate of potted tomato were analyzed.
RESULTS
Different ozone treatment had effects on leaf mildew, gray mold and fruit setting rate of tomato. The influence degree of three factors on leaf mildew, gray mold and fruit setting rate was from large to small, a > b > c, a > c > b, b > a > c. A quadratic regression model was established with the control effect of tomato leaf mildew, gray mold and fruit setting rate as response values, and the optimal parameter combination was determined: The ozone treatment concentration was 0.0465 g kg, the ozone treatment time was 30 min, and the ozone treatment times were twice a week. In this case, the control efficiency of tomato leaf mildew was 95.02%, the control effect of gray mold was 99.49%, and the fruit setting rate was 76.5%. The test parameters were accurate and reliable.
CONCLUSION
The ozone sterilization method proposed in this article is safe and green, and can provide theoretical support for the recovery and reconstruction of tomato disease in a glasshouse. © 2024 Society of Chemical Industry.
Topics: Ozone; Plant Diseases; Plant Leaves; Solanum lycopersicum; Sterilization
PubMed: 38308444
DOI: 10.1002/jsfa.13292 -
Environmental Pollution (Barking, Essex... Mar 2024Diclofenac (DCF) is a widely-used nonsteroidal anti-inflammatory drug that is routinely found in surface water bodies. While ozonation and ultraviolet (UV) radiation are...
Diclofenac (DCF) is a widely-used nonsteroidal anti-inflammatory drug that is routinely found in surface water bodies. While ozonation and ultraviolet (UV) radiation are commonly employed as disinfection methods in water treatment processes, the degradation of DCF in these processes occurs due to the strong oxidizing activity of the reactive oxygen species produced during both ozonation and UV radiation. Despite extensive studies reporting the removal and transformation of DCF through ozone and UV treatments, the potential hidden hazards of toxicity arising from these processes as well as the identification of the toxic transformation products have often been overlooked. In this study, various toxicities including microtoxicity, genotoxicity and antiestrogenicity were evaluated using multiple in-vitro bioassays. The transformation products were identified via ultra-performance liquid chromatography equipped with mass spectrometry (UPLC-MS). Correlation analysis was employed to gain deeper insight into the contributions of degradation products to overall toxicity. The results revealed that DCF possessed significant genotoxic and antiestrogenic effects, but displayed minimal microtoxicity. Microtoxic products such as those containing carbazole were generated during DCF degradation with ozone, UVA and UVC. Antiestrogenic products with dichloroaniline structures were observed in DCF ozonation but not in photodegradation by UVA and UVC. These findings highlighted the hidden risks associated with the disinfection of water containing micropollutants such as DCF.
Topics: Diclofenac; Chromatography, Liquid; Disinfection; Tandem Mass Spectrometry; Water Pollutants, Chemical; Water Purification; Ozone; Oxidation-Reduction
PubMed: 38278408
DOI: 10.1016/j.envpol.2024.123424 -
Environmental Science and Pollution... Feb 2024Disinfection is an important step in deep drinking water treatment technology. This study applies computational fluid dynamics to investigate and optimize the...
Disinfection is an important step in deep drinking water treatment technology. This study applies computational fluid dynamics to investigate and optimize the hydrodynamics inside the ozone contactor. ANSYS Fluent was used to solve all the control equations. A step method is used to simulate the residence time distribution. The mean residence time is simulated under the Eulerian framework. The deflectors are installed in chambers to direct flow. The deflectors allow for a more uniform flow and a longer mean residence time within the contactor. The baffling factor showed that the deflectors could reduce the short-circuit effect in the contactor and improve the disinfection efficiency by 34.6% compared to the original reactor. The Morrill factor coefficient is improved by 22.8% compared to the original reactor. According to the Aral-Demirel index, contactors with deflectors are significantly better than other baffle-type contactors. The presence of the deflectors increased the microbial inactivation efficiency from 95.3 to 96.5%. The optimal deflector height should be controlled between 30 and 60 mm.
Topics: Ozone; Computer Simulation; Disinfection; Water Purification; Hydrodynamics
PubMed: 38217804
DOI: 10.1007/s11356-024-31909-x -
The Science of the Total Environment Mar 2024Halobenzoquinones (HBQs) are a class of disinfection byproducts with high cytotoxicity and potential carcinogenicity, which have been widely detected in chlorination of...
Halobenzoquinones (HBQs) are a class of disinfection byproducts with high cytotoxicity and potential carcinogenicity, which have been widely detected in chlorination of drinking water and swimming pool water. However, to date, the formation of HBQs upon ozonation and the HBQ precursors have been overlooked. This study investigated the formation of chlorinated and dechlorinated HBQs from six dichlorophenol (DCP) isomers. The monomeric and dimeric HBQs were identified in all the ozonation effluents, exhibiting 1-100 times higher toxicity levels than their precursors. The sum of detected HBQs intensity had a satisfactory linear relation with the maximum toxic unit (R = 0.9657), indicating the primary toxicity contribution to the increased overall toxicity of effluents. Based on density functional theory calculations, when ozone attacks the para carbon to the hydroxyl group of 2,3-DCP, the probability of producing chlorinated HBQs is 80.41 %, indicating that the para carbon attack mainly resulted in the formation of monomeric HBQs. 2,3-dichlorophenoxy radicals were successfully detected in ozonated 2,3-DCP effluent through electron paramagnetic resonance and further validated using theoretical calculation, revealing the formation pathway of dimeric HBQs. The results indicate that chlorinated phenols, regardless of the positions of chlorine substitution, can potentially serve as precursors for both chlorinated and dechlorinated HBQs formation during ozonation.
Topics: Benzoquinones; Disinfection; Halogenation; Drinking Water; Phenols; Ozone; Carbon; Water Purification; Water Pollutants, Chemical; Allyl Compounds; Hydrocarbons, Chlorinated
PubMed: 38199341
DOI: 10.1016/j.scitotenv.2023.169860 -
Scientific Reports Jan 2024Exposure to air pollution is associated with many different health effects, especially cardiovascular and respiratory diseases. Additionally, highly significant links...
Exposure to air pollution is associated with many different health effects, especially cardiovascular and respiratory diseases. Additionally, highly significant links between exposure to air pollution and fertility, particularly male fertility was observed, however the studies regarding exposure to selected air pollutants and female fertility assessed by ovarian reserve are rare. Hence, the main aim of the study was to analyze relationship between exposure to ambient air pollution and ovarian reserve parameters among Polish women. The study population consisted of 511 women, who attended to infertility clinic because of diagnostic purposes. Participants filled in the questionnaire about social-demographic, lifestyle and health factors. Infertility specialists assessed ovarian parameters such as: antral follicle count (AFC) and concentration of hormones: Anti-Müllerian hormone (AMH), follicle stimulating hormone (FSH) and estradiol (E2). The air pollutants level (sulfur dioxide, nitrogen dioxide, carbon monoxide, ozone, particulate matters) were obtained via National Environmental Protection Inspectorate database. Significant negative association between PM and AHM (p = 0.032) as well as AFC (p = 0.044) was observed. Moreover, SO concentrations decrease AFC (p = 0.038). The results also suggest that PM, PM, SO exposure on antral follicle count may be more pronounced among women with a female factor infertility diagnosis. Additionally, exposure to PM and NOx on AFC and AMH was stronger among older women (> 35 years of age). To conclude, the present study found that air pollution could lead to decrease in follicle antral count and Anti-Müllerian hormone level, especially exposure to PM and SO thus the evidence suggest negative impact to ovarian reserve.
Topics: Female; Humans; Male; Aged; Ovarian Reserve; Anti-Mullerian Hormone; Infertility, Female; Estradiol; Air Pollution; Air Pollutants; Particulate Matter
PubMed: 38172170
DOI: 10.1038/s41598-023-50753-6