Antarctic ozone recovery

Since 1976, and more so since 1985, the Antarctic ozone level has suffered considerable depletion (termed as Antarctic ozone hole), attributed to the destructive effects of CFC compounds leaking into the atmosphere from man-made gadgets. The 12-month running means of South Pole Dobson ozone (monthly means, upto 1999 end only) were subjected to spectral analysis, which showed considerable, significant amplitudes for QBO (Quasi-biennial, 2-3 years) and QTO (Quasi-triennial, 3-4 years) oscillations, with a total range of 20-30 DU. When subtracted from the original values, a fairly smooth variation was seen, with a decrease from ~260 DU in 1986 to ~230 DU in 1996 (~12% decrease in 12-month running means), and an almost steady level thereafter. Thus, the net ozone variation at South Pole consists of two parts, (i) a long-term monotonically downward trend upto 1996 and a steady level thereafter and (ii) a superposed QBO-QTO oscillation. The chemical destruction effect is not likely to disappear soon, and may even increase if greenhouse effects, major volcanic eruptions or enhanced stratospheric cooling intervene. If the long-term level (i) remains steady, an extrapolation of the QBO-QTO patterns indicates that the ozone level is due for an increase from about 1999 end to about 2001 beginning. The purpose of the present analysis is to point out that, if such an increase of 20-30 DU occurs, it should not be misinterpreted as due to a decrease in chemical destruction, which scientists are eagerly awaiting due to the indication of a reduction in the halogen load in recent years due to adherence to the Montreal Protocol. After one or two years (in 2002), the extrapolated QBO-QTO oscillation may bring down the ozone level back again to the 1999 end level, and the apparent recovery may turn out to be a false signal.

Gene–environment interactions increase the risk of pediatric-onset multiple sclerosis associated with ozone pollution

Background: We previously reported a relationship between air pollutants and increased risk of pediatric-onset multiple sclerosis (POMS). Ozone is an air pollutant that may play a role in multiple sclerosis (MS) pathoetiology. CD86 is the only non-HLA gene associated with POMS for which expression on antigen-presenting cells (APCs) is changed in response to ozone exposure. Objectives: To examine the association between county-level ozone and POMS, and the interactions between ozone pollution, CD86, and HLA- DRB1*15, the strongest genetic variant associated with POMS. Methods: Cases and controls were enrolled in the Environmental and Genetic Risk Factors for Pediatric MS study of the US Network of Pediatric MS Centers. County-level-modeled ozone data were acquired from the CDC’s Environmental Tracking Network. Participants were assigned ozone values based on county of residence. Values were categorized into tertiles based on healthy controls. The association between ozone tertiles and having MS was assessed by logistic regression. Interactions between tertiles of ozone level and the GG genotype of the rs928264 (G/A) single nucleotide polymorphism (SNP) within CD86, and the presence of DRB1*15:01 ( DRB1*15) on odds of POMS were evaluated. Models were adjusted for age, sex, genetic ancestry, and mother’s education. Additive interaction was estimated using relative excess risk due to interaction (RERI) and attributable proportions (APs) of disease were calculated. Results: A total of 334 POMS cases and 565 controls contributed to the analyses. County-level ozone was associated with increased odds of POMS (odds ratio 2.47, 95% confidence interval (CI): 1.69–3.59 and 1.95, 95% CI: 1.32–2.88 for the upper two tertiles, respectively, compared with the lowest tertile). There was a significant additive interaction between high ozone tertiles and presence of DRB1*15, with a RERI of 2.21 (95% CI: 0.83–3.59) and an AP of 0.56 (95% CI: 0.33–0.79). Additive interaction between high ozone tertiles and the CD86 GG genotype was present, with a RERI of 1.60 (95% CI: 0.14–3.06) and an AP of 0.37 (95% CI: 0.001–0.75) compared to the lowest ozone tertile. AP results indicated that approximately half of the POMS risk in subjects can be attributed to the possible interaction between higher county-level ozone carrying either DRB1*15 or the CD86 GG genotype. Conclusions: In addition to the association between high county-level ozone and POMS, we report evidence for additive interactions between higher county-level ozone and DRB1*15 and the CD86 GG genotype. Identifying gene–environment interactions may provide mechanistic insight of biological processes at play in MS susceptibility. Our work suggests a possible role of APCs for county-level ozone-induced POMS risk.

Effect of Climate Change on Agricultural Production

Agricultural production is influenced by environmental factors such as temperature, air humidity, soil water, light intensity, and CO2 concentration. However, climate change has influenced the values of average temperature, precipitation, global atmospheric CO2 concentration, or ozone level. Thus, climate change could lead to different situations on plants and consequently influence agricultural production. With this chapter, the authors intend to research how climate change influences some plant metabolisms (such as photosynthesis, photorespiration, transpiration, among others) and therefore agricultural production.

Positive and negative influences of typhoons on tropospheric ozone over southern China

Based on an ensemble of 17 typhoons that made landfall between 2014 and 2018, we investigate the positive and negative influences of typhoons on tropospheric ozone over southern China. With respect to the proximity of typhoon centres and the typhoon developmental stages, we find that surface ozone is enhanced when typhoons are 400–1500 km away during the initial stages of development (e.g. from 1 d before to 1 d after typhoon genesis). The positive ozone anomalies reach 10–20 ppbv above the background ozone level on average. The maximum enhancement of surface ozone appears at a radial distance of 1100–1300 km from the typhoon centre during these initial stages. As the typhoons approach southern China, the influences of these systems switch to reducing ozone and, hence, lead to negative ozone anomalies of 6–9 ppbv. Exploring the linkages between ozone variations and typhoon-induced meteorological evolution, we find that increasing temperature and weak winds in the atmospheric boundary layer (ABL) and dominating downward motions promote ozone production and accumulation over the outskirts of typhoons during typhoon initial stages, whereas deteriorating weather, accompanied by dropping temperature, wind gales and convective activity, reduces the production and accumulation of surface ozone when typhoons are making landfall. We further examine the impacts of typhoons on tropospheric ozone profiles vertically, especially the influences of typhoon-induced stratospheric intrusions on lower troposphere and surface ozone. Based on temporally dense ozone profile observations, we find two high-ozone regions, located in the ABL and the middle to upper troposphere respectively, during different typhoon stages. On average, the high-ozone region in the ABL has a maximum ozone enhancement of 10–12 ppbv at 1–1.5 km altitude during the initial typhoon stages. In the high-ozone region in the middle to upper troposphere, ozone enhancement persists over a longer period with a maximum ozone enhancement of ∼ 10 ppbv at 7–8 km altitude shortly after typhoon genesis; this value increases to ∼ 30 ppbv near 12 km altitude when typhoons reach their maximum intensity. When typhoons make landfall, negative ozone anomalies appear and extend upward with a maximum ozone reduction of 14–18 ppbv at 5 km altitude and 20–25 ppbv at 11 km altitude. Although the overall tropospheric ozone is usually reduced during typhoon landfall, we find that five of eight typhoon samples induced ozone-rich air with a stratospheric origin above 4 km altitude; moreover, in three typhoon cases, the ozone-rich air intrusions can sink to the ABL. This suggests that the typhoon-induced stratospheric intrusions play an important role in surface ozone enhancement.

The Environmental and Social Determinants of Health Matter in a Pandemic: Predictors of COVID-19 Case and Death Rates in New York City

Our research objective was to determine which environmental and social factors were predictive of coronavirus disease 2019 (COVID-19) case and death rates in New York City (NYC), the original epicenter of the pandemic in the US, and any differential impacts among the boroughs. Data from various sources on the demographic, health, and environmental characteristics for NYC zip codes, neighborhoods, and boroughs were analyzed along with NYC government’s reported case and death rates by zip code. At the time of analysis, the Bronx had the highest COVID-19 case and death rates, while Manhattan had the lowest rates. Significant predictors of a higher COVID-19 case rate were determined to be proportion of residents aged 65 years plus; proportion of residents under 65 years with a disability; proportion of White residents; proportion of residents without health insurance; number of grocery stores; and a higher ozone level. For COVID-19 death rates, predictors include proportion of residents aged 65 years plus; proportion of residents who are not US citizens; proportion on food stamps; proportion of White residents; proportion of residents under 65 years without health insurance; and a higher level of ozone. Results across boroughs were mixed, which highlights the unique demographic, socioeconomic, and community characteristics of each borough. To reduce COVID-19 inequities, it is vital that the NYC government center the environmental and social determinants of health in policies and community-engaged interventions adapted to each borough.

Positive and negative influences of landfalling typhoons on tropospheric ozone over southern China

In this study, we use an ensemble of 17 landfalling typhoons over 2014–2018 to investigate the positive and negative influences of typhoons on tropospheric ozone over southern China. Referring to the proximity to typhoons and typhoon developmental stages, we found that surface ozone is enhanced when typhoons are 400–1500 km away during the initial stages of typhoons (e.g., from 1 day before and to 1 day after typhoon genesis). The positive ozone anomaly averagely reaches 10–20 ppbv at the daytime and 9 ppbv at nighttime compared with the background ozone level. Particularly, surface ozone at radial distances of 1100–1300 km is most significantly enhanced during these initial stages. As the typhoons approach and land in southern China, the influences of typhoons change from enhancing to reducing ozone. Surface ozone concentrations decrease with a negative ozone anomaly ranging between -12 % ~ -17 % relative to the background ozone level. We explore the physical linkages between typhoons, meteorological conditions and ozone variations. Results show that during typhoon initial stages, the increasing temperature and weak winds in the atmospheric boundary layer (ABL) and dominating downward motions promote ozone production and accumulation over the outskirts of typhoons. While the deteriorating weather accompanied by dropping temperature, wind gales and convective activity reduces the production and accumulation of surface ozone when typhoons are making landfalling. Variations of tropospheric ozone profiles during the differential developmental stages of landfalling typhoons are further examined to quantify the influences of typhoon-induced stratospheric intrusions on lower troposphere and surface ozone. Using temporally dense ozone vertical observations, we found two regions of high ozone concentrations separately located in the ABL and the middle-to-upper troposphere under the influences of typhoons. Averagely, the ozone enhancement maximizes around 10–12 ppbv at 1–1.5 km altitude at the typhoon initial stages. The ozone enhancement persists over a longer period in the middle-to-upper troposphere with a positive ozone anomaly of 10 ppbv at 7–8 km altitude shortly after typhoon genesis, and 30 ppbv near 12 km altitude when typhoons reach their maximum intensity. When typhoons are landing, a negative ozone anomaly appears and extends upward with a maximum ozone reduction of 14–18 ppbv at 5 km altitude and 20–25 ppbv at 11 km altitude. Though the overall tropospheric ozone is usually reduced during typhoon landfalling, we quantify that five of eight typhoon samples deduce ozone-rich air with the stratospheric origin (80 ppbv) above 4 km altitude, and in 3 typhoon cases the ozone-rich air intrusions (60 ppbv) can sink to the ABL. This suggests that the typhoon-induced stratospheric ozone-rich air intrusions play an important role in surface ozone enhancement.

Ozonized oils: a review of its quality control, stability and effectiveness in the treatment of Acne vulgaris

Acne affects most young people and its topical treatment with antibacterials is associated with increased bacterial resistance to antibiotics and adverse effects. As an alternative, ozone therapy stands out through the application of ozonized oils. The objective of this work was to raise the scientific evidence about the effectiveness in the treatment of acne, in addition to the techniques of characterization and stability of ozonated oils. This is an exploratory, descriptive study with a quantitative approach, based on the analysis of scientific references in a bibliographic review of the expository type, of the last 20 years. Among the selected references, only four manuscripts reporting clinical studies of ozone therapy, with controversial results. Seven articles with the physicochemical characterization of ozonated oils were found. The major part of manuscripts reported the use of sunflower, sesame and olive oil. The more common techniques used to characterize the ozonation process are the peroxide value (PV) and the iodine index (Ii), which represents the proportion of unsaturated groups, whose values increase and decrease, respectively with ozonization progress. The viscosity of oils is increased by the formation of polymeric peroxides; the FTIR spectrum, which identifies the decrease in the stretch bands C = C, in addition to ozone formation, monitored by NMR, are also employed. Increased antimicrobial activity has been demonstrated with the ozone level of the oils, but the activity against Cutibacterium acne has not been reported. Only two article reported satisfactory stability for 6 months of refrigerated ozonized oil or kept at room temperature, showing the need for more specific research to support the application of ozonized oils in the treatment of acne and stability data of these products.

Physiological Response of Garlic (Allium Sativum) to Elevated Tropospheric Ozone in High Altitude Region of Western Ghats, Tamil Nadu, India

A pot culture study was conducted at Horticultural Research Station, Ooty to assess the effect of ground level ozone on physiology in garlic plant and to find out the suitable remedial measures against ground level ozone. The potted soil was found to be acidic in nature with very low salt concentration, very high in organic carbon, medium in nitrogen, phosphorus and high in potassium. Elevated ozone levels (150ppb and 200ppb) had significantly reduced the garlic plant chlorophyll content, stomatal conductance, photosynthetic rate, pungency and total soluble solids. The highest chlorophyll content (33.97µmolm-2) was observed under ambient ozone level (T1) and the lowest chlorophyll content (12.68µmolm-2) was observed in elevated ozone exposure at 200 ppb (T3), the highest stomatal conductance (0.45mmol m-2s-1) was recorded in Ambient Ozone level + foliar spray 3% Panchagavya (T4), and the lowest stomatal conductance (0.11mmol m-2s-1) was observed in elevated ozone exposure at 200 ppb (T3). Since, the elevated ozone had significant reduction in photosynthetic rate in garlic, the lowest was observed (0.82µmol CO2 s-1m-2) in T3- Elevated ozone exposure at 200 ppb and the highest photosynthetic rate (3.02µmol CO2 s-1m-2) was observed in treatment T4- Ambient Ozone level + foliar spray 3% Panchagavya after a week. When coming to quality of garlic bulbs, the highest pungency content was found in Ambient Ozone level + foliar spray 0.1% Ascorbic acid and the lowest was observed in Elevated ozone exposure at 200 ppb (T3) furthermore, in observing the garlic quality where total soluble solids (TSS) showed that the treatment Ambient Ozone level + foliar spray 3% Panchagavya (40.00°Brix) as highest and the treatment Elevated ozone exposure at 200 ppb (T3) recorded the lowest. Thus the tropospheric ozone has detrimental impact on physiological responses, which will reduce crop growth and yield. The ozone protectants helped in scavenging the O3 from apoplast of the crops and among the ozone protectants, neem oil acted as a good ozone scavenger followed by ascorbic acid and panchagavya to improve the physiological response of garlic plant under elevated tropospheric ozone levels.