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1.
Int J Biometeorol ; 2022 Oct 20.
Article in English | MEDLINE | ID: covidwho-2075424

ABSTRACT

Due to the rapid increase in the novel coronavirus virulence, the entire world implemented the practice of lockdown along with the constraint of human movement. The obligation of quarantine halted most of the commercial and industrial movement that prominently disturbed the distinct key environmental parameters directly associated with the plant's and animal's health conditions. In this regard, the research aims to study the sudden shut-off of vehicular activity impact on the naturally growing lichen of the genus Pyxine cocoes. The results showed an increase in the pigments, Fv/Fm ratio, and phytohormones during the lockdown and concurrently the decreasing levels in the post-lockdown period. Interestingly, modulations in the phytohormones occur in the lockdown period as compared to the post-lockdown period. The metals Al, Cr, and Fe show the highest increasing trends in the unlocking period, whereas As, Cd, Pb, Cu, Hg, Mn, and Zn show very little variation during the running and post-lockdown phases. The lichen photosynthetic activity justifies further examination as initial biological indicators of the abrupt environmental variations prompted by such types of atmospheric situations and, to a greater extent, for the risk assessment in the near future. In conclusion, stress-phytohormone and amino acids play a significant role as stress reducers. Although lichens are well known for long environmental assessment, the present study will provide qualitative and quantitative variation in physiochemical changes in the short term and sudden environmental fluctuations. HIGHLIGHTS: • Qualitative and quantitative variation in biochemical parameters in lichen during and post-lockdown period was analyzed. • Stress-phytohormone and amino acids play a significant role as stress reducers. • Selectivity sequence reflection in heavy metal accumulation may be used in future studies.

2.
Atmosphere ; 13(9), 2022.
Article in English | Web of Science | ID: covidwho-2071181

ABSTRACT

In this study, the levels of fine particulate matter (PM2.5), polycyclic aromatic hydrocarbons (PAHs) and nitro-PAHs (NPAHs) in PM2.5 samples were determined from 2020 to 2021 in Singapore. For analysis convenience, the sampling period was classified according to two monsoon periods and the inter-monsoon period. Considering Singapore's typically tropical monsoon climate, the four seasons were divided into the northeast monsoon season (NE), southwest monsoon season (SW), presouthwest monsoon season (PSW) and prenortheast monsoon season (PNE)). The PM2.5 concentration reached 17.1 +/- 8.38 mu g/m(3), which was slightly higher than that in 2015, and the average PAH concentration continuously declined during the sampling period compared to that reported in previous studies in 2006 and 2015. This is the first report of NPAHs in Singapore indicating a concentration of 13.1 +/- 10.7 pg/m(3). The seasonal variation in the PAH and NPAH concentrations in PM2.5 did not obviously differ owing to the unique geographical location and almost uniform climate changes in Singapore. Diagnostic ratios revealed that PAHs and NPAHs mainly originated from local vehicle emissions during all seasons. 2-Nitropyrene (2-NP) and 2-nitrofluoranthene (2-NFR) in Singapore were mainly formed under the daytime OH-initiated reaction pathway. Combined with airmass backward trajectory analysis, the Indonesia air mass could have influenced Singapore's air pollution levels in PSW. However, these survey results showed that no effect was found on the concentrations of PAHs and NPAHs in PM2.5 in Indonesia during SW because of Indonesia's efforts in the environment. It is worth noting that air masses from southern China could impact the PAH and NPAH concentrations according to long-range transportation during the NE. The results of the total incremental lifetime cancer risk (ILCR) via three exposure routes (ingestion, inhalation and dermal absorption) for males and females during the four seasons indicated a low long-term potential carcinogenic risk, with values ranging from 10(-10) to 10(-7). This study systematically explains the latest pollution conditions, sources, and potential health risks in Singapore, and comprehensively analyses the impact of the tropical monsoon system on air pollution in Singapore, providing a new perspective on the transmission mechanism of global air pollution.

3.
Knowl Based Syst ; 258: 109996, 2022 Dec 22.
Article in English | MEDLINE | ID: covidwho-2069433

ABSTRACT

Research on the correlation analysis between COVID-19 and air pollution has attracted increasing attention since the COVID-19 pandemic. While many relevant issues have been widely studied, research into ambient air pollutant concentration prediction (APCP) during COVID-19 is still in its infancy. Most of the existing study on APCP is based on machine learning methods, which are not suitable for APCP during COVID-19 due to the different distribution of historical observations before and after the pandemic. Therefore, to fulfill the predictive task based on the historical observations with a different distribution, this paper proposes an improved transfer learning model combined with machine learning for APCP during COVID-19. Specifically, this paper employs the Gaussian mixture method and an optimization algorithm to obtain a new source domain similar to the target domain for further transfer learning. Then, several commonly used machine learning models are trained in the new source domain, and these well-trained models are transferred to the target domain to obtain APCP results. Based on the real-world dataset, the experimental results suggest that, by using the improved machine learning methods based on transfer learning, our method can achieve the prediction with significantly high accuracy. In terms of managerial insights, the effects of influential factors are analyzed according to the relationship between these influential factors and prediction results, while their importance is ranked through their average marginal contribution and partial dependence plots.

4.
Int J Environ Res Public Health ; 19(19)2022 Oct 08.
Article in English | MEDLINE | ID: covidwho-2066081

ABSTRACT

Under the clean air action plans and the lockdown to constrain the coronavirus disease 2019 (COVID-19), the air quality improved significantly. However, fine particulate matter (PM2.5) pollution still occurred on the North China Plain (NCP). This study analyzed the variations of PM2.5, nitrogen dioxide (NO2), sulfur dioxide (SO2), carbon monoxide (CO), and ozone (O3) during 2017-2021 on the northern (Beijing) and southern (Henan) edges of the NCP. Furthermore, the drivers for the PM2.5 pollution episodes pre- to post-COVID-19 in Beijing and Henan were explored by combining air pollutant and meteorological datasets and the weighted potential source contribution function. Results showed air quality generally improved during 2017-2021, except for a slight rebound (3.6%) in NO2 concentration in 2021 in Beijing. Notably, the O3 concentration began to decrease significantly in 2020. The COVID-19 lockdown resulted in a sharp drop in the concentrations of PM2.5, NO2, SO2, and CO in February of 2020, but PM2.5 and CO in Beijing exhibited a delayed decrease in March. For Beijing, the PM2.5 pollution was driven by the initial regional transport and later secondary formation under adverse meteorology. For Henan, the PM2.5 pollution was driven by the primary emissions under the persistent high humidity and stable atmospheric conditions, superimposing small-scale regional transport. Low wind speed, shallow boundary layer, and high humidity are major drivers of heavy PM2.5 pollution. These results provide an important reference for setting mitigation measures not only for the NCP but for the entire world.


Subject(s)
Air Pollutants , Air Pollution , COVID-19 , Ozone , Air Pollutants/analysis , Air Pollution/analysis , COVID-19/epidemiology , Carbon Monoxide/analysis , China/epidemiology , Communicable Disease Control , Environmental Monitoring/methods , Humans , Nitrogen Dioxide/analysis , Ozone/analysis , Particulate Matter/analysis , Sulfur Dioxide/analysis
5.
Environmental Science & Technology ; 44(8):82-90, 2021.
Article in Chinese, English | CAB Abstracts | ID: covidwho-2056700

ABSTRACT

In order to trace and monitor the atmospheric heavy metal pollution in Xichang City, an investigation activity was carried out with a sort of moss (Taxiphyllum taxirameum) (packed in moss bags) as a biological indicator for monitoring heavy metal pollution. The investigation was conducted from the period from April 2019 to April 2020, during which two grave emergency events occurred during spring monitoring period from January 15 to April 15, 2020, i.e., COVID-19 and "3.30"severe forest fire in Xichang, which inevitably affected the atmospheric quality. Based on the concentration analysis of 12 kinds of heavy metal, including Al, Cr, Fe, Cu, Ni, Pb, Mn, Hg, Zn, V, As and Ba contained in the moss and the local meteorological data, comparing those informative data before and after the time when the emergency events toke place, the paper made an analysis on the impacts of two enormous emergency events on the air pollution of heavy metal in Xichang. The results showed that total amount of enrichment of above-mentioned 12 heavy metals in spring (January 15 to April 15, 2020) is (12.85 +or- 1.57) mg/g, which was significantly higher than in the other three seasons (p < 0.01), but no significant discrepancies about the total enrichment amount in the other three seasons (p > 0.05). Primarily because of COVID-19 pandemic, the level of motor vehicles emissions cut down, and the decrease of the tourism in the related areas perhaps causing the decline of pollution of Pb. In addition, the decrease of unbalanced emission of pollutants led to a noted increase of atmospheric oxidation in urban area, thus boosting the formation of secondary particulate matter, and the particulate matter from surrounding industrial sources was transported into the urban area;as a result, remarkable increases of Hg concentration of moss within the moss bags were detected downwind the industrial area located in the urban fringe. Consequently, the investigation showed that the moss-bag method is an effective biological tool for monitoring air heavy metal pollution, which could reflect the impacts of major pollution events on air quality.

6.
Atmospheric Chemistry and Physics ; 22(18):12705-12726, 2022.
Article in English | ProQuest Central | ID: covidwho-2056005

ABSTRACT

This study investigated the spatiotemporal variabilities in nitrogen dioxide (NO2), formaldehyde (HCHO), ozone (O3), and light-absorbing aerosols within the Greater Tokyo Area, Japan, which is the most populous metropolitan area in the world. The analysis is based on total tropospheric column, partial tropospheric column (within the boundary layer), and in situ observations retrieved from multiple platforms as well as additional information obtained from reanalysis and box model simulations. This study mainly covers the 2013–2020 period, focusing on 2020 when air quality was influenced by the coronavirus 2019 (COVID-19) pandemic. Although total and partial tropospheric NO2 columns were reduced by an average of about 10 % in 2020, reductions exceeding 40 % occurred in some areas during the pandemic state of emergency. Light-absorbing aerosol levels within the boundary layer were also reduced for most of 2020, while smaller fluctuations in HCHO and O3 were observed. The significantly enhanced degree of weekly cycling of NO2, HCHO, and light-absorbing aerosol found in urban areas during 2020 suggests that, in contrast to other countries, mobility in Japan also dropped on weekends. We conclude that, despite the lack of strict mobility restrictions in Japan, widespread adherence to recommendations designed to limit the COVID-19 spread resulted in unique air quality improvements.

7.
Nigerian Journal of Technological Development ; 19(3):206-222, 2022.
Article in English | Scopus | ID: covidwho-2055815

ABSTRACT

Trends and sources of air pollution at twenty-five traffic Intersections (TIs) before and during covid-19 lockdown were investigated in Ibadan, Nigeria. The relationships among climatic parameters, vehicular counts and ten air pollutants which includes particulate matter (PM1, PM2.5, PM10 & Total Suspended Particles-TSP) and gaseous pollutants (CO, NO2, SO2, NH3, total volatile organic compounds-TVOCs, and ground level O3) measured simultaneously at TIs were analysed. Results indicated significant decrease in mean concentrations of all pollutants studied except NO2 with 212% increase during the study period. Concentrations of gaseous pollutants CO, SO2, NH3, TVOCs and ground level O3 reduced by 7.92%, 24.80%, 1.58%, 44.08% and 4.28%, respectively while particulates concentrations of PM1, PM2.5, PM10 and TSP concentrations decreased by 49.64%, 60.79%, 81.21% and 84.17%, respectively during lockdown. An integrated source apportionment approach using Pearson’s correlation, Airflow backward trajectories arriving in the study area and Principal component analysis (PCA) identified vehicular emission as the primary source of studied air pollutants at TIs before and during lockdown in Ibadan. Emission from residences, roadside fuel combustion and local air transport of pollutants from nearby upwind areas with industries and farming activities were identified as secondary sources of air pollution affecting the study area. © 2022, University of Ilorin, Faculty of Engineering and Technology. All rights reserved.

8.
Aerosol and Air Quality Research ; 22(10), 2022.
Article in English | ProQuest Central | ID: covidwho-2055783

ABSTRACT

The study aims to reveal the impact of three sequential strict-lockdowns of COVID-19 measures on the air pollutants including NO2, SO2, PM10, and PM2.5 in Ulaanbaatar, Mongolia during November 2020–February 2021 based on air quality network and satellite data. Based on measurements of automatic air quality sites in Ulaanbaatar, we found a substantial decrease in NO2 (up to 45%), PM10 (72%), and PM2.5 (59%) compared to the same periods in the previous five years. On the other hand, up to a threefold increase in SO2 concentration was seen. Compared to 2015–2020, the number of days exceeding the national air quality standard level of NO2 decreased by 55% during November 2020–February 2021. A similar trend was observed for PM10 and PM2.5 (30% and 14%, respectively). Conversely, days exceeding the national air quality standard level of SO2 increased by 58%. The third strict-lockdown exhibited significant reductions in pollutant concentrations. The percentage exceeding the national standard level for NO2, PM10, and PM2.5 constituted 23%, 50%, and 67% during the lockdown periods while it was 89%, 84%, and 91%, respectively, for the same periods in the previous five years. Even though Sentinel 5P-TROPOMI data do not fully reflect the above findings, they add valuable insights into the spatial pollution pattern during strict-lockdown and non-lockdown periods. The study demonstrates that measures taken during the strict-lockdown periods clearly influenced the values of daily patterns of NO2, PM10, and PM2.5 concentrations. On the contrary, it is important to note that SO2 concentration increased during the last two winter months after 2019.

9.
Discrete Dynamics in Nature and Society ; 2022, 2022.
Article in English | ProQuest Central | ID: covidwho-2053436

ABSTRACT

The world economy, since the outbreak of the coronavirus epidemic, has undergone profound changes. Especially since the coronavirus became the norm, how to achieve rapid economic revitalization has become a problem that countries have to face. In order to analyze how the government should promote the enterprises’ economic revitalization and effectively control pollution under the normalized epidemic situation, this paper analyzes the economic revitalization and pollution control problems faced by enterprises under the normalized epidemic situation by using the evolutionary game method. Through the analysis of the evolutionary game model, we draw the following conclusions: (1) Discovered by comparing two different incentives mechanism and penalties mechanism, the dynamic incentives mechanism, and penalties mechanism has a better effect on the process of enterprises’ economic revitalization, and it also can reduce the discharge of enterprises’ pollutants. (2) In terms of discharge reduction effect, penalties have a better effect than incentives. Compared with incentives, in the process of the economic revitalization of enterprises, in order to reduce pollution discharge, the government can adopt dynamic penalties strategies. This paper analyzes what the government should do when enterprises face the problems of economic revitalization and pollution control. This study can not only provide suggestions for the government in the process of governance but also provide countermeasures for the economic revitalization of enterprises.

10.
2021 Ieee Asia-Pacific Conference on Geoscience, Electronics and Remote Sensing Technology (Agers-2021) ; : 102-108, 2021.
Article in English | Web of Science | ID: covidwho-2042711

ABSTRACT

COVID-19 or Coronavirus Disease 2019 has become a global pandemic until several countries have implemented social distancing in restrictions on human activities. The Indonesian Government, in early 2020, set a PSBB (Large-Scale Social Restriction) policy. Still, as the COVID-19 Pandemic progressed, the Indonesian Government finally changed the PSBB and implemented the PPKM (Enforcement of Community Activity Restrictions) policy. COVID-19 has an impact on decreasing human and industrial activities. On the other hand, this will be beneficial due to a decrease in air pollutants. Pollutants come from motor vehicle fumes or other industrial activities. The types of pollutants carried out in this research are Carbon Monoxide (CO), Ozone (O3), Sulfur Dioxide (S02), and Nitrogen Dioxide (NO2). Using Sentinel-5P Imagery, which can record pollutant activity with the daily temporal resolution, the effect of the number of pollutants on the COVID-19 Pandemic can be investigated using the Google Earth Engine and the correlation test method to relate the effect of pollutant concentrations to BMKG meteorological data. The correlation test of pollutant data on sentinel 5P images with BMKG data shows a strong correlation of 0.5045 and 0.795 in Central Java. In addition, changes in the decrease in CO, NO2, and O3 gases occurred in November 2020 - December 2020. Monitoring of pollutants in Java During the COVID-19 Pandemic was packaged in the Website and Google Earth Engine. According to users, the application obtained a usability test result of 89%

11.
Journal of Cleaner Production ; 375:134189, 2022.
Article in English | ScienceDirect | ID: covidwho-2041906

ABSTRACT

Rotating biological contactors (RBCs) were first used as pretreatment units for hybrid constructed wetlands (HCWs) in practical engineering to treat polluted river water. The experimental results during 2019–2021, except the period of global COVID-19 pandemic (January to April, November and December in 2020), indicated the average removal efficiencies of ammonia nitrogen (NH4+–N), total phosphorous (TP), and chemical oxygen demand (COD) were 95.06%, 41.03%, and 45.46%, which met the Chinese Environmental Quality Standards Ⅰ, Ⅲ, Ⅳ (CEQS Ⅰ, Ⅲ, Ⅳ), respectively. RBCs and HCWs had synergistic and complementary effects on purification efficiency, especially on nitrogen removal. The remarkable nitrification efficiency of RBCs was not influenced by temperature and influent loads. The relative abundances of microorganisms at HCWs in cold seasons were comparable to that in warm seasons, which promoted the recovery of decontamination efficiency after overwintering. These results support RBCs combined with HCWs (R-HCWs) is an effective polluted river purification process, providing a new perspective on water ecological restoration.

12.
Boletin de Malariologia y Salud Ambiental ; 61(Edicion Especial II 2021):3-15, 2021.
Article in Spanish | CAB Abstracts | ID: covidwho-2040734

ABSTRACT

Environmental pollution begins with the industrial era and increases after the Second World War with the rise of technology. In the 1970s, man began to become aware of the seriousness of this progressive and irreparable damage. Ecology and related sciences are developed and actions are implemented everywhere to manage or alleviate the damage. Pollution can directly alter the components of an ecosystem, water, air or soils, but it can also occur due to the presence of unusual physical or physicochemical phenomena, such as heat or ionizing radiation. Its effects are manifested mainly by damage to ecosystems and therefore damage to the health of human beings, animals, plants, land or water (Nebel, 1999;Clark, 2003). Today the ecological disasters of London, Donora, Minamata, Chernobyl, Bophal, the Persian Gulf, the Danube originating in Baia Mare or those of oil in the seas are well known (Baxter, 1991). In Peru, we know of the environmental damage of the City of Oroya, Lake Junin, the Choropampa spill, and urban contamination by lead dust from deposits of mineral concentrates in Callao. According to the Pan American Health Organization, there are 20,000 confirmed cases of COVID-19 in the Amazon Basin (Martin, 2020). Gold miners and illegal loggers are exposing indigenous communities to considerable health risks, a situation that could have severe consequences given the poor response capacity of hospitals and health services in the region. Therefore, the spread of the virus in these communities could imply a tragedy that, in addition to the human losses, could, in turn, affect traditional knowledge and produce negative effects on the governance of the region. As a result, there could be even more deforestation in the future. Differential policies to serve ethnic populations in the region are an urgent need (Bermudez et al., 2020;Velez et al., 2020a). That is why this research set out to establish the Influence of industrialization on environmental health: Historical vision from the industrial revolution to the COVID19 pandemic.

13.
Environmental Science & Technology ; 45(2):202-209, 2022.
Article in Chinese, English | CAB Abstracts | ID: covidwho-2040545

ABSTRACT

Studies have shown that during the 2020 epidemic control period, air quality data has been"abnormal", but due to differences in geography and demographic factors, the survey results in different regions are not consistent. The purpose of the study is to analyze the difference in air quality under the control of the two epidemics in Shijiazhuang City, further explore the impact of control measures on air quality, and provide reference and ideas for improving air quality and adjusting atmospheric control measures. Based on the China Air Quality Online Monitoring and Analysis Platform and Zhenqi.com, with Shijiazhuang air quality as the research object, the air quality and meteorological monitoring data in the past 6 years have been collected and sorted, and the t-test and rank-sum test methods are used to analyze the air pollution status and change characteristics in the two epidemic control periods based on the air quality monitoring data of Shijiazhuang City during the epidemic control period from January 5 to February 8,2021, with comparison with the data of the same time period in 2019. With reference to changes in meteorological factors, the impact of epidemic control on air quality was comprehensively analyzed. Results indicate that in 2021, the social blockade measures against the epidemic have greatly reduced the concentrations of various pollutants. The concentrations of PM2.5,PM10,SO2,CO2, and NO2 have dropped by 52.13%,40.62%,74.93%,55.53%,44.59%,(p<0.05),respectively, compared with the same period before the epidemic (2016-2019 average levels).O3 pollution increased, and the concentration increased by 49.40%compared to before the epidemic (p<0.05);the severity of epidemic control measures also has a certain impact on air quality compared with the epidemic blockade carried out in the same period in 2020.PM2.5,PM10,CO2,and NO2 during the epidemic control period in 2021 decreased by 54.85%,37.79%,52.36%and 31.15%,respectively,(p<0.05). Analysis of meteorological factors showed that there was no significant difference in the average temperature and wind speed in Shijiazhuang during the survey period from January 5 to February 8 in the past 6 years. Compared with before the epidemic, there was no significant change in the relative humidity during the epidemic period in 2021. The relative humidity in the same period in 2020 was 65.28% higher than before the epidemic (p<0.05). There were obvious differences in air quality during the two epidemic control periods in Shijiazhuang, but the meteorological factors did not show corresponding changes. The change in air quality may be related to the strictness of the epidemic control measures and the order of implementation.

14.
Atmospheric Chemistry and Physics ; 22(18):12207-12220, 2022.
Article in English | ProQuest Central | ID: covidwho-2040264

ABSTRACT

During the COVID-19 lockdown, the dramatic reduction of anthropogenic emissions provided a unique opportunity to investigate the effects of reduced anthropogenic activity and primary emissions on atmospheric chemical processes and the consequent formation of secondary pollutants. Here, we utilize comprehensive observations to examine the response of atmospheric new particle formation (NPF) to the changes in the atmospheric chemical cocktail. We find that the main clustering process was unaffected by the drastically reduced traffic emissions, and the formation rate of 1.5 nm particles remained unaltered. However, particle survival probability was enhanced due to an increased particle growth rate (GR) during the lockdown period, explaining the enhanced NPF activity in earlier studies. For GR at 1.5–3 nm, sulfuric acid (SA) was the main contributor at high temperatures, whilst there were unaccounted contributing vapors at low temperatures. For GR at 3–7 and 7–15 nm, oxygenated organic molecules (OOMs) played a major role. Surprisingly, OOM composition and volatility were insensitive to the large change of atmospheric NOx concentration;instead the associated high particle growth rates and high OOM concentration during the lockdown period were mostly caused by the enhanced atmospheric oxidative capacity. Overall, our findings suggest a limited role of traffic emissions in NPF.

15.
Atmospheric Chemistry and Physics ; 22(18):12153-12166, 2022.
Article in English | ProQuest Central | ID: covidwho-2040263

ABSTRACT

A knowledge gap exists concerning how chemical composition and sources respond to implemented policy control measures for aerosols, particularly in a semi-arid region. To address this, a single year's offline measurement was conducted in Hohhot, a semi-arid city in northern China, to reveal the driving factors of severe air pollution in a semi-arid region and assess the impact of the COVID-19 lockdown measures on chemical characteristics and sources of PM2.5. Organic matter, mineral dust, sulfate and nitrate accounted for 31.5 %, 14.2 %, 13.4 % and 12.3 % of the total PM2.5 mass, respectively. Coal combustion, vehicular emission, crustal source and secondary inorganic aerosols were the main sources of PM2.5 in Hohhot, at 38.3 %, 35.0 %, 13.5 %, and 11.4 %, respectively. Due to the coupling effect of emission reduction and improved atmospheric conditions, the concentration of secondary inorganic components, organic matter and elemental carbon declined substantially from the pre-lockdown (pre-LD) period to the lockdown (LD) and post-lockdown (post-LD) periods. The source contribution of secondary inorganic aerosols increased (from 21.1 % to 37.8 %), whereas the contribution of vehicular emission reduced (from 35.5 % to 4.4 %) due to lockdown measures. The rapid generation of secondary inorganic components caused by unfavorable meteorological conditions during lockdown led to serious pollution. This study elucidates the complex relationship between air quality and environmental policy.

16.
IOP Conference Series : Earth and Environmental Science ; 33, 2022.
Article in English | CAB Abstracts | ID: covidwho-2037315

ABSTRACT

The quick response of contaminants from various sources and the extensive deterioration of rivers' water quality may harm our biodiversity, aquatic creatures, and environment. The depletion of this river water quality can be caused by both natural and manmade factors and this condition will jeopardize its use for many human uses and may harm the residents' health. Our concerning phenomenon prompted this investigation to study the primary pollutant source in two rivers near Gebeng. A total of ten sampling stations from both Balok and Tunggak Rivers were selected and physicochemical parameters reading were measured monthly afore and in COVID-19 Pandemic spread in Malaysia from March 2019 to October 2020. Later, the Cluster and Principal Component Analysis (CA and PCA) were applied. CA grouped the ten sampling stations into three clusters which are upstream areas that were considered as most polluted. PCA yields only four significant components that represented 90.68% of the total variability. The findings of this study can provide useful information regarding the current state of river water quality in the Gebeng area, and the proposed method can be used as a strategy for sustaining the use of water resources in support of long-term development goals.

17.
Environmental Research Letters ; 17(10):104003, 2022.
Article in English | ProQuest Central | ID: covidwho-2037309

ABSTRACT

Latin America, as other regions in the world, imposed mobility restrictions to tackle the COVID-19 pandemic. Although recent research has analyzed the effect of mobility restrictions on air quality in several regions, a scarce literature explores the causal effects of the lockdowns in Latin America at a city scale whose results may guide local policymaking. This article, based on a quasi-experimental approach, estimates the causal short-term impacts of lockdowns on air quality considering the influence of forest fires on pollution in four megacities in Latin America (Bogotá, Mexico City, Santiago, and Sao Paulo). Results show that nitrogen oxides and carbon monoxide consistently declined (from 16% to 68%), nevertheless, fine particles rarely decreased across cities. Only Bogotá exhibited an overall reduction in fine particles (45% for PM2.5). Mexico City obtained the lowest reduction in pollutants, whereas Bogotá outperformed other cities in several pollutants. Evidence from mobility statistics supports the decrease in air pollution by a reduction in driving, transit use, and other mobility indicators.

18.
J Drug Deliv Sci Technol ; 76: 103805, 2022 Oct.
Article in English | MEDLINE | ID: covidwho-2031441

ABSTRACT

Cannabidiol (CBD) was formulated as a metered dose inhaler (CBD-MDI) and evaluated in vitro for its efficacy as an inhaled dosage form against inflammation caused by the SARS-CoV-2 virus, lipopolysaccharide (LPS) from Escherichia coli, silica particles, nicotine, and coal tar. A CBD-MDI formulation was prepared with 50 mg of CBD in 10 mL for a CBD dose of 250 µg/puff. The formulation ingredients included CBD, absolute ethanol as a cosolvent, and HFA-134a as the propellant. High aerosol performance of CBD-MDI was obtained with mass median aerodynamic diameter of 1.25 ± 0.01 µm, geometric standard deviation of 1.75 ± 0.00, emitted dose of 244.7 ± 2.1 µg, and fine particle dose of 122.0 ± 1.6 µg. The cytotoxicity and anti-inflammatory effectiveness of CBD-MDI were performed in alveolar macrophage (NR8383) and co-culture of alveolar macrophage (NR8383) and human lung adenocarcinoma (A549) cell line. CBD delivered from an MDI was safe on respiratory cells and did not trigger an immune response in alveolar macrophages. CBD-MDI effectively reduced the generation of cytokines in immune cells treated with viral antigen S-RBD, bacterial antigen LPS, silica particles, and coal tar. The efficacy of CBD-MDI was comparable to budesonide. Furthermore, the findings demonstrated that the use of CBD-MDI was more effective in treatment rather than prevention when inflammation was induced by either a viral or bacterial stimulant.

19.
International Journal of Environmental Technology and Management ; 25(5):406-426, 2022.
Article in English | ProQuest Central | ID: covidwho-2029802

ABSTRACT

The purpose of this study was to investigate and assess how restrictive COVID-19 precautions affect air quality in Zonguldak, as well as to determine the relationship between air quality and meteorological variables under these conditions. Daily PM2.5, PM10, SO2, and NOx concentrations and meteorological data, from 1 March to 31 May 2018, 2019, and 2020 were collected for this research. During the 2020 restrictive COVID-19 precautions, it was determined that concentrations of air pollutants were different and low based on the 95% confidence interval by using paired t-test samples. Meteorological variables were found to be similar to previous years, and the correlation between them and air pollutants was found to be significant (P < 0.01) but low according to Pearson correlations. As a result, meteorological variables were determined to have no direct effect on the low concentrations of air quality emissions during the 2020 pandemic. The overall findings revealed that anthropogenic impact has a negative impact on air quality and the air quality had improved during the COVID pandemic. Furthermore, the restriction on the region's coalmines during the COVID-19 pandemic has significant impact on the improvement of air quality.

20.
2nd International Conference on Medical Imaging and Additive Manufacturing, ICMIAM 2022 ; 12179, 2022.
Article in English | Scopus | ID: covidwho-2029448

ABSTRACT

Plasmonic nanobiosensors have an enormous application range. It has the capacity to detect a wide variety of substances including metal, protein and even nucleic acids due to the superiority of SPR and LSPR. Plasmonic biosensors have been widely applied in the field of disease diagnosis, environmental conservation and food safety, eliminating barriers of traditional diagnosis methods and providing sensitive, quick and label-free devices. The applications of plasmonic biosensors in detection of many concerned diseases like cancer and SARS-CoV-2 are making an improvement on our medical condition. In the field of environmental protection, plasmonic-based biosensors also show great potential. They can efficiently detect two main types of contaminants, inorganic heavy metals involving Pb, Cd, As and Hg, and organic pollutants like polycyclic aromatic hydrocarbons (PAHs). Plasmonic biosensors could also overcome challenges on food allergen detection. This paper mainly focusses on SPR and LSPR-based nanobiosensors' application in environmental protection, food safety and health-care. © 2022 SPIE. Downloading of the is permitted for personal use only.

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