-
American Journal of Respiratory and... Oct 2019
Topics: Air Pollutants; Air Pollution; Cause of Death; Ozone; United States
PubMed: 31185178
DOI: 10.1164/rccm.201906-1105ED -
The Science of the Total Environment Nov 2022Bisphenol F (BPF) and bisphenol S (BPS) are the most employed substitutes of bisphenol A (BPA), after being restricted by legislation in different countries because of...
Bisphenol F (BPF) and bisphenol S (BPS) are the most employed substitutes of bisphenol A (BPA), after being restricted by legislation in different countries because of its endocrine disrupting behaviour. In the present work, a deep study was performed about the reactivity of BPF and BPS with ozone and hydroxyl radical. Firstly, the second order rate constants of ozone with the di-protonated, mono-protonated and deprotonated species of both bisphenols were determined to be 2.38 × 10, 1.31 × 10 and 1.43 × 10 M s for BPF and 5.01, 2.82 × 10 and 1.09 × 10 M s for BPS. Then, the second order rate constants for the reaction of hydroxyl radical with BPF and BPS were established through UV/HO and UV experiments at pH 7, resulting in the values of 8.60 × 10 and 6.60 × 10 M s, respectively. Finally, a study regarding the transformation products (TPs) from the reaction of both bisphenols with molecular ozone and hydroxyl radical was also performed. Hydroxylation in the ortho position of the phenol rings was observed as main degradation pathway. Additionally, most of the TPs were accumulated over the reactions at relatively high oxidant doses.
Topics: Benzhydryl Compounds; Hydrogen Peroxide; Hydroxyl Radical; Kinetics; Ozone; Phenols
PubMed: 35817118
DOI: 10.1016/j.scitotenv.2022.157173 -
Brazilian Journal of Biology = Revista... 2022Ozone gas is considered as a safe antimicrobial agent in food industries. Here, we evaluated the antifungal and antiaflatoxigenic activities of ozone against fungal...
Ozone gas is considered as a safe antimicrobial agent in food industries. Here, we evaluated the antifungal and antiaflatoxigenic activities of ozone against fungal contamination in nuts. The most predominant fungal genera in nuts were Aspergillus, Penicillium, Fusarium, and Rhizopus. Ozone (4 ppm) significantly reduced the fungal sporulation of A. flavus and their aflatoxin production. Interestingly, ozone treatment of nuts reduced the total fungal count and increased aflatoxins degradation by approximately 95% and 85%, respectively. Ozone displayed high efficiency to increase the permeability of cell membrane and injury of cell wall of fungi. Increasing the exposure time of ozone in nuts up to 180 minutes showed to reduce the total lipid, carbohydrates, and protein by around 41.2%, 42.7% and 38.4% respectively, in pistachio, almond and peanuts. In conclusion, ozonation is a suitable decontaminating approach for reducing the microbial load in nuts, when used with suitable exposure time.
Topics: Aflatoxins; Antifungal Agents; Nutritive Value; Nuts; Ozone
PubMed: 35766710
DOI: 10.1590/1519-6984.263814 -
Pediatric Pulmonology May 2023Ground level ozone is a potent respiratory toxicant with decades of accumulated data demonstrating respiratory harms to children. Despite the ubiquity of ozone in the... (Review)
Review
Ground level ozone is a potent respiratory toxicant with decades of accumulated data demonstrating respiratory harms to children. Despite the ubiquity of ozone in the United States, impacting both urban and rural communities, the associated harms of exposure to this important air pollutant are often infrequently or inadequately covered during medical training including pulmonary specialization. Thus, many providers caring for children's respiratory health may have limited knowledge of the harms which may result in reduced discussion of ozone pollution during clinical encounters. Further, the current US air quality standard for ozone does not adequately protect children. In this nonsystematic review, we present basic background information for healthcare providers caring for children's respiratory health, review the US process for setting air quality standards, discuss the respiratory harms of ozone for healthy children and those with underlying respiratory disease, highlight the urgent need for a more protective ozone standard to adequately protect children's respiratory health, review impacts of climate change on ozone levels, and provide information for discussion in clinical encounters.
Topics: Child; Humans; United States; Ozone; Air Pollution; Air Pollutants; Lung; Respiratory Tract Diseases
PubMed: 36815617
DOI: 10.1002/ppul.26368 -
Trends in Biochemical Sciences Dec 2021Tropospheric ozone (O) is among the most damaging air pollutant to plants. Plants alter the atmospheric O concentration in two distinct ways: (i) by the emission of... (Review)
Review
Tropospheric ozone (O) is among the most damaging air pollutant to plants. Plants alter the atmospheric O concentration in two distinct ways: (i) by the emission of volatile organic compounds (VOCs) that are precursors of O and (ii) by dry deposition, which includes diffusion of O into vegetation through stomata and destruction by nonstomatal pathways. Isoprene, monoterpenes, and higher terpenoids are emitted by plants in quantities that alter tropospheric O. Deposition of O into vegetation is related to stomatal conductance, leaf structural traits, and the detoxification capacity of the apoplast. The biochemical fate of O once it enters leaves and reacts with aqueous surfaces is largely unknown, but new techniques for the tracking and identification of initial products have the potential to open the black box.
Topics: Air Pollutants; Ozone; Plant Leaves; Plants; Volatile Organic Compounds
PubMed: 34303585
DOI: 10.1016/j.tibs.2021.06.007 -
Photochemical & Photobiological... May 2023This assessment provides a comprehensive update of the effects of changes in stratospheric ozone and other factors (aerosols, surface reflectivity, solar activity, and...
This assessment provides a comprehensive update of the effects of changes in stratospheric ozone and other factors (aerosols, surface reflectivity, solar activity, and climate) on the intensity of ultraviolet (UV) radiation at the Earth's surface. The assessment is performed in the context of the Montreal Protocol on Substances that Deplete the Ozone Layer and its Amendments and Adjustments. Changes in UV radiation at low- and mid-latitudes (0-60°) during the last 25 years have generally been small (e.g., typically less than 4% per decade, increasing at some sites and decreasing at others) and were mostly driven by changes in cloud cover and atmospheric aerosol content, caused partly by climate change and partly by measures to control tropospheric pollution. Without the Montreal Protocol, erythemal (sunburning) UV irradiance at northern and southern latitudes of less than 50° would have increased by 10-20% between 1996 and 2020. For southern latitudes exceeding 50°, the UV Index (UVI) would have surged by between 25% (year-round at the southern tip of South America) and more than 100% (South Pole in spring). Variability of erythemal irradiance in Antarctica was very large during the last four years. In spring 2019, erythemal UV radiation was at the minimum of the historical (1991-2018) range at the South Pole, while near record-high values were observed in spring 2020, which were up to 80% above the historical mean. In the Arctic, some of the highest erythemal irradiances on record were measured in March and April 2020. For example in March 2020, the monthly average UVI over a site in the Canadian Arctic was up to 70% higher than the historical (2005-2019) average, often exceeding this mean by three standard deviations. Under the presumption that all countries will adhere to the Montreal Protocol in the future and that atmospheric aerosol concentrations remain constant, erythemal irradiance at mid-latitudes (30-60°) is projected to decrease between 2015 and 2090 by 2-5% in the north and by 4-6% in the south due to recovering ozone. Changes projected for the tropics are ≤ 3%. However, in industrial regions that are currently affected by air pollution, UV radiation will increase as measures to reduce air pollutants will gradually restore UV radiation intensities to those of a cleaner atmosphere. Since most substances controlled by the Montreal Protocol are also greenhouse gases, the phase-out of these substances may have avoided warming by 0.5-1.0 °C over mid-latitude regions of the continents, and by more than 1.0 °C in the Arctic; however, the uncertainty of these calculations is large. We also assess the effects of changes in stratospheric ozone on climate, focusing on the poleward shift of climate zones, and discuss the role of the small Antarctic ozone hole in 2019 on the devastating "Black Summer" fires in Australia. Additional topics include the assessment of advances in measuring and modeling of UV radiation; methods for determining personal UV exposure; the effect of solar radiation management (stratospheric aerosol injections) on UV radiation relevant for plants; and possible revisions to the vitamin D action spectrum, which describes the wavelength dependence of the synthesis of previtamin D in human skin upon exposure to UV radiation.
Topics: Humans; Stratospheric Ozone; Ultraviolet Rays; Canada; Ozone; Erythema; Aerosols
PubMed: 37083996
DOI: 10.1007/s43630-023-00371-y -
Toxins Jul 2020Mycotoxins are secondary metabolites produced by some filamentous fungi, which can cause toxicity in animal species, including humans. Because of their high... (Review)
Review
Mycotoxins are secondary metabolites produced by some filamentous fungi, which can cause toxicity in animal species, including humans. Because of their high toxicological impacts, mycotoxins have received significant consideration, leading to the definition of strict legislative thresholds and limits in many areas of the world. Mycotoxins can reduce farm profits not only through reduced crop quality and product refusal, but also through a reduction in animal productivity and health. This paper briefly addresses the impacts of mycotoxin contamination of feed and food on animal and human health, and describes the main pre- and post-harvest systems to control their levels, including genetic, agronomic, biological, chemical, and physical methods. It so highlights (i) the lack of effective and straightforward solutions to control mycotoxin contamination in the field, at pre-harvest, as well as later post-harvest; and (ii) the increasing demand for novel methods to control mycotoxin infections, intoxications, and diseases, without leaving toxic chemical residues in the food and feed chain. Thus, the broad objective of the present study was to review the literature on the use of ozone for mycotoxin decontamination, proposing this gaseous air pollutant as a powerful tool to detoxify mycotoxins from feed and food.
Topics: Animal Feed; Animals; Decontamination; Food Contamination; Humans; Mycotoxins; Oxidants; Ozone
PubMed: 32751684
DOI: 10.3390/toxins12080486 -
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 -
Proceedings of the National Academy of... Feb 2021Outdoor ozone transported indoors initiates oxidative chemistry, forming volatile organic products. The influence of ozone chemistry on indoor air composition has not...
Outdoor ozone transported indoors initiates oxidative chemistry, forming volatile organic products. The influence of ozone chemistry on indoor air composition has not been directly quantified in normally occupied residences. Here, we explore indoor ozone chemistry in a house in California with two adult inhabitants. We utilize space- and time-resolved measurements of ozone and volatile organic compounds (VOCs) acquired over an 8-wk summer campaign. Despite overall low indoor ozone concentrations (mean value of 4.3 ppb) and a relatively low indoor ozone decay constant (1.3 h), we identified multiple VOCs exhibiting clear contributions from ozone-initiated chemistry indoors. These chemicals include 6-methyl-5-hepten-2-one (6-MHO), 4-oxopentanal (4-OPA), nonenal, and C8-C12 saturated aldehydes, which are among the commonly reported products from laboratory studies of ozone interactions with indoor surfaces and with human skin lipids. These VOCs together accounted for ≥12% molecular yield with respect to house-wide consumed ozone, with the highest net product yield for nonanal (≥3.5%), followed by 6-MHO (2.7%) and 4-OPA (2.6%). Although 6-MHO and 4-OPA are prominent ozonolysis products of skin lipids (specifically squalene), ozone reaction with the body envelopes of the two occupants in this house are insufficient to explain the observed yields. Relatedly, we observed that ozone-driven chemistry continued to produce 6-MHO and 4-OPA even after the occupants had been away from the house for 5 d. These observations provide evidence that skin lipids transferred to indoor surfaces made substantial contributions to ozone reactivity in the studied house.
Topics: Air Pollutants; Air Pollution, Indoor; Aldehydes; California; Environmental Monitoring; Humans; Ketones; Lipids; Oxidation-Reduction; Ozone; Squalene; Volatile Organic Compounds
PubMed: 33526680
DOI: 10.1073/pnas.2018140118 -
Molecules (Basel, Switzerland) Sep 2022Saskatoon berry fruits are a valuable source of micro- and macronutrients, sugars, and compounds with health-promoting properties, the properties of which change during...
Saskatoon berry fruits are a valuable source of micro- and macronutrients, sugars, and compounds with health-promoting properties, the properties of which change during storage. This study presents the effects of applied gaseous ozone at 10 ppm for 15 and 30 min on microbiological stability, sugar content, and bioactive compounds for three cultivars and three clones of Saskatoon berry fruit. The ozonation process had a positive effect on reducing the microbial load of the fruit, which was observed on day 7 of storage for the two variants of ozonation time of 15 and 30 min compared to the control and also on the sugar profile of the "Thiessen" fruit, as well as clones no 5/6 and type H compared to the control sample, which was non-ozonated fruit. In the Saskatoon berry fruits analyzed, 21 polyphenolic compounds were identified, of which four belonged to the anthocyanin group whose main representative was the 3-O-glucoside cyanidin. The ascorbic acid content and antioxidant activity (determined by DPPH· and ABTS· methods) varied according to the cultivar and clone of the Saskatoon berry fruits analyzed and the ozone exposure time.
Topics: Anthocyanins; Antioxidants; Ascorbic Acid; Fruit; Glucosides; Ozone; Rosaceae; Sugars
PubMed: 36234982
DOI: 10.3390/molecules27196446