ABSTRACT
[Background] The coronavirus disease 2019 (COVID-19) was first detected in December 2019. To combat the disease, a series of strict measures were adopted across the country, which led of improved air quality. This provides an opportunity to discuss the impact of human activities on air quality. [Objective] This study investigates the air quality changes in Shijiazhuang, and analyzes the impacts of epidemic prevention and control measures on air quality, so as to provide reference and ideas for further improving air quality and prevention and control measures. [Methods] The air quality data were collected online from https://www.zq12369.com/ and https://aqicn.org/city/shijiazhuang/cn/. Comparisons in air quality index (AQI) and the concentrations of air pollutants (PM2.5, PM10, SO2, CO, NO2, and O3) were made between the period from December 2019 to June 2020 (reference) and the same period from 2016 to 2019 by t-test and chi-square test. [Results] The daily average AQI dropped by 25.38% in Shijiazhuang during the COVID-19 prevention and control compared with the some period from 2016 to 2019 (t=6.28, P < 0.05). The proportions of pollution days during the COVID-19 outbreak in Shijiazhuang were PM2.5 (44.56%), O3 (31.09%), PM10 (23.83%), and NO2 (2.59%) successively, the pollution days of PM10 decreased significantly (chi2=3.86, P < 0.05) compared with 2016-2019, but during traffic lockdown the numbers of pollution days of PM2.5 and in the mid stage of prevention the number of pollution days of O3 increased (P < 0.05). Compared with the control period, the concentrations of the six air pollutants decreased to varying degrees (P < 0.05), especially SO2 dropped by 55.36%. [Conclusion] The measures taken for COVID-19 control and prevention have reduced the pollution sources and emissions, which resulted in better general air quality of Shijiazhuang City, but have aggravated the pollution of O3 and other pollutants. It is necessary to further explore the causes for the aggravation of O3 pollution in order to formulate reasonable air quality control strategies.Copyright © 2021, Shanghai Municipal Center for Disease Control and Prevention. All rights reserved.
ABSTRACT
Handan is a typical city affected by regional particulate pollution. In order to investigate particulate matter (PM) characterization, source contributions and health risks for the general populations, we collected PM samples at two sites affected by a pollution event (12–18 May 2020) during the COVID-19 pandemic and analyzed the major components (SNA, OCEC, WSIIs, and metal elements). A PCA-MLR model was used for source apportionment. The carcinogenic and non-carcinogenic risks caused by metal elements in the PM were assessed. The results show that the renewal of old neighborhoods significantly influences local PM, and primarily the PM10;the average contribution to PM10 was 27 μg/m3. The source apportionment has indicated that all other elements came from dust, except Cd, Pb and Zn, and the contribution of the dust source to PM was 60.4%. As PM2.5 grew to PM10, the PM changed from basic to acidic, resulting in a lower NH4+ concentration in PM10 than PM2.5. The carcinogenic risk of PM10 was more than 1 × 10−6 for both children and adults, and the excess mortality caused by the renewal of the community increased by 23%. Authorities should pay more attention to the impact of renewal on air quality. The backward trajectory and PSCF calculations show that both local sources and short-distance transport contribute to PM—local sources for PM10, and short-distance transport in southern Hebei, northern Henan and northern Anhui for PM2.5, SO2 and NO2. © 2023 by the authors.
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In this study, the temporal evolution and sources of water-soluble organic carbon (WSOC) in submicron particles at an urban background site in Elche (Spain) were investigated. Measurements of PM1 (N = 200) were carried out over one year (2021). Samples were analysed for organic carbon (OC), elemental carbon (EC), WSOC, levoglucosan, elements and major ions. A positive matrix factorization (PMF) analysis was performed in order to identify the sources of WSOC on an annual and a monthly basis. During the study period, traffic restrictions due to COVID-19 led to lower concentrations of PM1 and carbonaceous compounds than expected. The WSOC annual average mass concentration was 0.95 mugm-3, with maximum values during the colder months. The apportionment results indicate that the biomass burning (BB) source contributed 30.63% to WSOC levels, road traffic (RT) accounted for 23.90% of the WSOC, while the contribution of a source related to secondary organic aerosol formation (ammonium sulfate-AS) was 33.80%. Minor sources of WSOC were: soil dust (SD) and secondary nitrate (SN), which contributed 7.44% and 4.22%, respectively, to WSOC concentrations. The WSOC/OC ratio did not exhibit significant variations during the study period, since source contributions were similar for WSOC and OC. The highest values of this ratio were recorded in summer, due to the higher contribution from the AS source to WSOC concentrations.Copyright © 2023 The Authors
ABSTRACT
Background: More than 2 years since COVID-19's first cases were reported in 2019. Diagnosis of COVID-19 is a key to controlling the pandemic. Sample for COVID-19 testing is collected by naso-oro-pharyngeal swab. This procedure is often uncomfortable and requires a trained examiner. Exhaled breath contains thousands of volatile organic compounds (VOC) which are likely to change during infection. Aims and objectives: This study aims to analyze the difference of VOC in the exhaled breath between COVID-19 and healthy subjects. Method(s): A cross-sectional study was carried out recruiting 90 confirmed cases of COVID-19 and 42 healthy subjects. A sample of exhaled breath was collected by using a 500 ml airbag in both groups. Contained VOC was analyzed using an arrayed sensor breath analyzer to quantify the concentration of CO2, C7H8, C6H14, CH2O, NH4, TVOC, NO2, PM1.0, CO, NH3and Acetone. Statistical analysis was conducted using Mann whitney test. Result(s): The median of CO2, C6H14, NH4, TVOC, NO2, and Acetone are significantly higher in COVID-19 patients compared to healthy subjects (respectively 1175.1 vs 607.3, 0.47 vs 0.0, 1.05 vs 0.0, 146.6 vs 0.05, 1.55 vs 0.04, and 0.23 vs 0.0) while C7H8, CH2O, PM1.0, CO, and NH3are significantly lower (respectively 0.0 vs 0.92, 0.01 vs 0.55, 0.0 vs 4.13, 0.0 vs 0.24, and 0.67 vs 1.99;all with p-value of <0.05.). Furthermore, we found NH4, Acetone, NH3, and CO are positively correlate with severity of COVID-19. Conclusion(s): COVID-19 patients emit distinctive VOC profiles in comparison with healthy subjects.
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Acute wheezing in children due to underlying asthma or airways hypersensitivity (including allergic rhinitis) can be exacerbated by infectious and non-infectious causes. Of the infectious causes, seasonal rhinoviruses are the most common. Particulate airborne pollutants (PM2.5, PM10) can also play a role. During the COVID-19 pandemic, we observed changes in the pattern of paediatric emergency department (PED) presentations for acute wheezing. In this retrospective observational cohort study, data was extracted for children (0-18 years) presenting to the PED during 2018-2021, whose illness episodes were coded as 'asthma' or 'viral induced wheeze', along with their age, ethnicity, gender, and clinical outcomes, from hospital databases. The Figure shows the number of PED presentations for acute wheezing during 2018-2021, with annotations to explain the changing patterns. The number of cases presenting during the pandemic years 2020-2021 were similar to those in 2018-2019 in the same months, except for April-June 2020, July-August 2020, November 2020 and January-March 2021. Decreases in PED presentations coincided with periods of enforced national and local lockdowns, likely due to parental reluctance to expose their children to SARS-CoV-2 in a hospital setting. In addition, fluctuations in the incidence of rhinovirus infections, as shown by national sentinel surveillance data, likely contributed to changes in case numbers. Higher and lower incidence of rhinovirus infections tended to increase and decrease the number of presentations, respectively. Surprisingly, the level of airborne particulates (PM2.5, PM10) showed no correlation with these PED presentations for acute wheezing.
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Students spend nearly one third of their typical day in the school environment, where they may be exposed to harmful air pollutants. A consolidated knowledge base of interventions to reduce this exposure is required for making informed decisions on their implementation and wider uptake. We attempt to fill this knowledge gap by synthesising the existing scientific literature on different school-based air pollution exposure interventions, their efficiency, suitability, and limitations. We assessed technological (air purifiers, HVAC - Heating Ventilation and Air Conditioning etc.), behavioural, physical barriers, structural, school-commute and policy and regulatory interventions. Studies suggest that the removal efficiency of air purifiers for PM2.5, PM10, PM1 and BC can be up to 57 %, 34 %, 70 % and 58 %, respectively, depending on the air purification technology compared with control levels in classroom. The HVAC system combined with high efficiency filters has BC, PM10 and PM2.5 removal efficiency up to 97 %, 34 % and 30 %, respectively. Citizen science campaigns are effective in reducing the indoor air pollutants' exposure up to 94 %. The concentration of PM10, NO2, O3, BC and PNC can be reduced by up to 60 %, 59 %, 16 %, 63 % and 77 %, respectively as compared to control conditions, by installing green infrastructure (GI) as a physical barrier. School commute interventions can reduce NO2 concentration by up to 23 %. The in-cabin concentration reduction of up to 77 % for PM2.5, 43 % for PNC, 89 % for BC, 74 % for PM10 and 75 % for NO2, along with 94 % reduction in tailpipe emission of total particles, can be achieved using clean fuels and retrofits. No stand-alone method is found as the absolute solution for controlling pollutants exposure, their combined application can be effective in most of the scenarios. More research is needed on assessing combined interventions, and their operational synchronisation for getting the optimum results.Copyright © 2022 The Authors
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The world population is demonstrating an increasing awareness about the ecological impacts of air quality, including impacts on human health. The Veneto region and, more generally, the Po Valley (NE Italy), are characterised by frequent exceedance of limit values for air quality, in particular particulate matter (PM10), which causes these areas to be listed as hotspots;thus, this region has some of the worst air pollution in Europe. The aim of the current research was to analyse a 10 year-long time series of air quality data (2011–2021) in the Veneto region to investigate the influence of selected factors on air quality, such as natural processes (meteorological conditions), environmental policies, and health emergency measures due to the COVID-19 pandemic. Generally, the considered pollutants, PM10, NO, and NO2, presented a decreasing trend during the last ten years. The reduction in nitrogen oxides was clearly improved after the implementation of a specific environmental protocol (the "New Agreement of Po Valley Basin”). Conversely, the PM10 concentration seemed to be affected by other important emission sources, such as domestic heating systems, agricultural activities, and animal farms, which are not as strongly regulated as emission sources such as traffic. The 2020 lockdown mainly influenced nitrogen oxide concentrations.
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Particle size distribution is a major factor in the health and climate effects of ambient aerosols, and it shows a large variation depending on the prevailing atmospheric emission sources. In this work, the particle number size distributions of ambient air were investigated at a suburban detached housing area in northern Helsinki, Finland, during a half-year period from winter to summer of 2020. The measurements were conducted with a scanning mobility particle sizer (SMPS) with a particle size range of 16–698 nm (mobility diameter), and the events with a dominant particle source were identified systematically from the data based on the time of the day and different particle physical and chemical properties. During the measurement period, four different types of events with a dominant contribution from either wood-burning (WB), traffic (TRA), secondary biogenic (BIO), or long-range transported (LRT) aerosol were observed. The particle size was the largest for the LRT events followed by BIO, WB, and TRA events with the geometric mean diameters of 72, 62, 57, and 41 nm, respectively. BIO and LRT produced the largest particle mode sizes followed by WB, and TRA with the modes of 69, 69, 46, and 25 nm, respectively. Each event type had also a noticeably different shape of the average number size distribution (NSD). In addition to the evaluation of NSDs representing different particle sources, also the effects of COVID-19 lockdown on specific aerosol properties were studied as during the measurement period the COVID-19 restrictions took place greatly reducing the traffic volumes in the Helsinki area in the spring of 2020. These restrictions had a significant contribution to reducing the concentrations of NOx and black carbon originating from fossil fuel combustion concentration, but insignificant effects on other studied variables such as number concentration and size distribution or particle mass concentrations (PM1, PM2.5, or PM10). © 2022 The Authors
ABSTRACT
Rationale: The aerosolized solid, liquid, mix-phased particles are the Particulate Matter or PM having serious health impacts. In the recent years with the unprecedented situation of COVID-19 pandemic, it became a necessity that the scientific world comes forward with an objective of developing more equipment for air purification with novel technology to combat airborne pathogen, aeroallergen and viruses. We have applied AFLPCO Nanotechnology to build equipment and mask. Methods: We built a fiberglass chamber to evaluate the capacity of the AFL-Mask to prevent entry of particulate matters and pathogens. To evaluate the air in the chamber, we used a LightHouse Handheld Particle Counter to sample airborne particles. We have recorded the particle concentrations at time-intervals to determine the percentage of particles entering the other chamber with the mask placed in the junction dividing the chamber. Results: This mask involves a 4-stage filtration system designed to combat all forms of airborne pathogens including bacteria, viruses, mold spores and harmful VOCs. We found that the AFL-Mask was efficient in preventing any particulate matter including PM2.5, PM10, bacterial and fungal spores and VOCs. Conclusions: The AFL-Mask and AFLPCO air purifiers built for long-term use to improve the inhaled air quality. The ergonomic design with padded lining and straps and improved filtration technology made the AFL-Mask a superior mask that provides a continuous airflow to prevent suffocation, troubled breathing and fluctuating blood pressure, especially pertaining to patients with cardiovascular or pulmonary issues. AFLPCO airpurifers were efficient in improving IAQ.
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India is placed under a national lockdown from 24 March to 3 May 2020 due of the COVID-19 epidemic. The forced limits caused the amount of pollution in cities around the nation to drop significantly in just a few days, which sparked talks about lockdown as the most effective alternative techniques that might be used to reduce air pollution. The purpose of the current paper was ultimately to examine the air quality situation throughout the shutdown time scientifically with particular attention to several industrial regions in Jodhpur City. We used the Air Quality Index (AQI) to depict the geographical pattern of air quality before to and during lockdown using air quality data for seven pollutant metrics (PM10, PM2.5, SO2, NO2, etc.) from several monitoring sites located around the city of Jodhpur. The investigation also revealed that PM10 and PM2.5 were the air pollutants that caused the highest sub-index and the air quality index. Therefore, it is now necessary to organize operations in industrial regions to reduce air pollution emissions, since failure to do so might result in a hazardous condition in the future. The outcomes showed that the air quality dramatically improves during lockdown. Since the study demonstrated how pollution source control may reduce air quality, it is seen to be a valuable addition to the regulatory authorities' toolkit. The environment may be cured by temporary source control in a reasonable time frame.
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Background: Coronavirus disease 2019 (COVID-19) is an invisible enemy that has made people observe issues such as eating habits, personal hygiene, and environmental factors that may affect their immune systems. Objectives: Because air pollution can affect the immune system, it is necessary to examine the relationship between air quality parameters and COVID-19. Methods: his study examines the correlation between air quality and COVID-19 considering 7 air pollutants: PM10, SO2, CO, NO2, NOx, NO, and O3. The confirmed COVID-19 cases were considered from 9 provinces, accounting for 78% of the total cases in Turkey. The required data were collected from the websites of the country’s relevant official institutions. Two statistical tests, the Pearson correlation, and Spearman Rho were conducted to determine any potential linear and monotonic relationships. Results: Based on both test results, a significant positive correlation was observed between air SO2 content and the number of COVID-19 cases in Turkey. Conclusion: The outcomes could help identify provincial actions or measures.
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Introduction: Indoor air quality have a great impact on physical and psychological health of employees working in buildings. IndianOil Institute of Petroleum Management (IiPM), located in National Capital Region of Delhi(NCR) is a premiere institute consisting of multiple training halls & auditoriums. In view of COVID-19 pandemic, modifications were carried out in air handling unit system at IiPM. Materials and methods: A detailed study of air movements, intake and return path was carried to find out measures to ensure adequate air exchanges. Additional air inlets with Dual PM10 filters were fixed on all air intake paths to reduce the pollutant level in air entering the building. The air handling unit at the institute was also fitted with special grade air filter for bringing down the PM2.5 level below 60. Special grade filters filtered the pollutants and reduced the pollutant level of air. An online air image sensor was installed to measure the quality of ambient air after filtration. Stand-alone air cleaner/filter units were also installed in training halls, lobbies and waiting areas. Result: Following modifications there was improvement in air quality by 90%. This resulted in building confidence level and provided a stress-free safe environment for employees working at the institute. Employees working at IiPM confirmed reduction in eye irritation, headaches and fatigue due to air pollution. Discussion: Installation of air filters inside the building helps in improving air quality which in turn prevents common health issues at workplace. This has prompted us to provide similar solutions in other office buildings in NC
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Introduction Studies on air pollution and COVID-19 are limited to the first pandemic wave (April/June 2020) and by their ecological design. Objectives To investigate the association between airborne pollutants and SARS-CoV-2 incidence up to March 2021 in the Varese city (Lombardy region), with individual-level data on exposures, disease and confounders. Methods Varese citizens aged 18+ years as of Dec31st,2019 were linked by residential address to 2018 average annual exposure to outdoor concentrations of PM2.5, PM10, NO2, NO and O3 modelled using FARM chemical-transport model (linkage coverage: 97.4%). Citizens were linked to Regional datasets for COVID-19 case ascertainment (positive nasophar-yngeal swab specimens) and to define age, sex, residential care home living, population density and comorbidities. We estimated rate ratios and additional number of COVID-19 cases for 1 mg/m3 increase in air pollutants, from single-and bi-pol-lutant Poisson regression models. Results Among the 62.848 residents, we observed 4408 COVID-19 cases. Yearly average PM2.5 exposure was 12.5 mg/m3. Cumulative incidence curves suggest an increased risk for PM2.5>13.5 mg/m3 in correspondence of downtrend periods in the pandemic curve. Age, residential care home living, history of stroke, medications for diabetes, hypertension and obstructive airway disease were independently associated with COVID-19 rate. In single-pollutant multivariate model, 1 mg/m3 increase in PM2.5 was associated with 5.1% increase in COVID-19 rate (95%CI: 2.7%-7.5%), corresponding to 294 additional cases per 100.000 person-years. These figures were confirmed in bi-pollutant models and after excluding subjects in residential care homes. Similar findings were observed for PM10, NO2 and NO. O3 was associated with a 2% decrease in disease rate, the association being reversed in bi-pollutant models. Conclusions In our study, long term exposure to low-levels of air pollutants, especially PM2.5, positively affected COVID-19 incidence. Causality warrants confirmation in future studies;meanwhile, governmental efforts to further reduce air pollution should continue.