Air quality changes in Shijiazhuang during COVID-19 outbreak

[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.

Characterization and Source Apportionment of PM in Handan—A Case Study during the COVID-19

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.

Particulate matter air pollution and COVID-19 risk: A systematic review

Introduction/Aim: Ecological studies indicate ambient particulate matter >=2.5 mm (PM 2.5) air pollution is associated with poorer COVID-19 outcomes. However, these studies cannot account for individual heterogeneity and often lack precision in estimates of PM 2.5 exposure. We summarise evidence relating on individual-level data to determine whether PM 2.5 exposure increases the risk of COVID-19 infection, severe disease and death. Method(s): We conducted a systematic review of relevant case-control and cohort studies, searching Medline, Embase and the WHO COVID-19 databases. Study quality was evaluated using the Newcastle-Ottawa Scale. Result(s): N = 18 studies met the inclusion criteria. Generally, PM 2.5 exposure was significantly associated with higher rates of COVID-19 infection (all 7 studies positive) and severe COVID-19 disease (8 of 9 studies positive, 1 null). The effects on mortality were mixed but indicative of a positive association (4 of 6 studies positive, 2 null). Most studies were rated 'good' quality (13 of 18 studies), though there were still methodological issues;few used individual-level data to adjust for important confounders like socioeconomic status (3 of 18 studies), instead using area-based indicators (12 of 18 studies) or not adjusting for it at all (3 of 18 studies). Most studies with severe disease (9 of 10 studies) and mortality outcomes (5 of 6 studies) were based on people already diagnosed COVID-19, potentially introducing collider bias. Conclusion(s): There is strong evidence that ambient particulate matter air pollution increases the risk of COVID-19 infection, and weaker evidence of increases in risk of severe disease and mortality.

Coronavirus Disease (COVID-19) Possible Transmission Routes and Alleviation Strategies

Coronavirus disease is a contagious respiratory ailment that has spread significantly around the world. Most cases of COVID-19 are spread from person to person by coming into contact with respiratory droplets that are released when an infected person coughs or sneezes. In this manuscript, we have highlighted the possible transmission of COVID-19 through food, water, air and paper. In the case of food, we have extensively covered the transmission of COVID-19 through meat, frozen foods, food packaging and food market along with the incidences worldwide. In the nextsection, we have highlighted the different components of air which are responsible for the transmission and also covered its relation with PM 2.5 incidence. The SARS-CoV-2 was isolated from sewage water/wastewater of various countries namely the United States, India, Australia, Netherlands and France signifying that wastewater can be a mode of virus transmission. The paper circulation by the infected COVID-19 patients can also be a virus conveyance route. It can be concluded that SARS-CoV-2 can therefore be transmitted indirectly through food via the workers involved in food packing or food marts.By following general safety precautions (wearing masks, using hand sanitisers, cleaning and disinfecting contact surfaces, and avoiding close contact), heating and using chemicals like ethanol (67-71%), sodium hypochlorite (0.1%) and hydrogen peroxide (0.5%) on environmental surfaces, along with vaccination, it is possible to reduce the spread of the SARS-CoV-2 virus.Copyright © 2023 The International Journal of Pharmaceutical Research and Allied Sciences (IJPRAS).

What Impact Will Worsening Air Pollution Have on the Burden of Covid-19?

Background: Evidence suggests association between long-term exposure to air pollutants and increased risk of becoming infected with SARS-CoV- 2, the causative agent of COVID-19, and increased severity of COVID-19. However, it remains unclear whether breathing more polluted air over many years affects susceptibility to infection or only affects disease severity, with uncertainty around the intensity of these associations. It has been estimated that anthropogenic emissions have contributed to over 10% of the over 660 million cases of SARS-CoV-2 and the over 7.5 million COVID-19 deaths reported worldwide over the course of the pandemic. Furthermore, as the world continues to warm and if air pollution levels increase, then so might the burden of respiratory infectious disease, including COVID-19. Method(s): Here we explore the potential impact of long-term exposure to increasing levels of particulate matter 2.5 microns or less in diameter (PM2.5) (+1 to +5 mug/m3) assuming an association on either (1) SARS-CoV-2 susceptibility or (2) COVID-19 disease severity by projecting SARS-CoV-2 infections and COVID-19-related hospital admissions over a two-year period. Simulations were conducted using a SARS-CoV-2 transmission model in a global setting capturing age and comorbidity risk, considering seasonality, emerging variants, and vaccination and treatment options. We model linear, log, and log10 relationships between these associations. Result(s): We show that if long-term exposure to higher levels of air pollution only affects COVID-19 severity, then as expected, the projected number of COVID-19-related hospitalisations would proportionally increase. However, if exposure directly affects the susceptibility of becoming infected, then while infections would be higher, hospitalizations would also be even higher due to the potential for onward transmission. This aligns with associations between air pollution and other respiratory infections and their associated health outcomes. Conclusion(s): The anticipated additional impact air pollution is having on the public health burden of respiratory infectious disease, like COVID-19, should be considered in strategic action plans to mitigate and adapt to changing levels of air pollution. It is important to better understand at which point air pollution affects SARS-CoV-2 infection acquisition through to disease progression, to enable improved protection and to better support those most vulnerable. Modelled impact of air pollution on COVID-19. The projected cumulative impact of long-term exposure to incrementally higher PM2.5 levels (+1 to +5 mug/m3) affecting either SARS-CoV-2 susceptibility or COVID-19 disease severity on cumulative SARS-CoV-2 infections and COVID-19-related hospital admissions over a two-year period in a global setting of 100,000 people. Age and comorbidity risk are captured, seasonality considered, and it is assumed SARS-CoV-2 variants of concern (with 10% more infectious and 20% more immune-evading than the previous variant, and Omicron-level severity) emerge every six months, and COVID-19 vaccination and treatment (monoclonalantibody PrEP and antivirals) are implemented for all those eligible. While the associations between PM2.5 exposure and either SARS-CoV-2 susceptibility or COVID-19 disease severity remains unclear and there is much uncertainty around estimated assumptions, here we show a modelled log10 relationship between these two potential associations. COVID-19: coronavirus disease 2019. PM2.5: particulate matter 2.5 microns or less in diameter. PrEP: pre-exposure prophylaxis. SARS-CoV-2: severe acute respiratory syndrome coronavirus 2.

OCCUCON 2023 Abstracts

The proceedings contain 32 papers. The topics discussed include: assessment of workplace indoor fine particle exposure and pulmonary function parameters among ceramic tile industry workers of West India;respiratory morbidities in school children of critically polluted industrial area of Gujarat - a prospective observational study;morbidities among workers of an organochlorine pesticide industry;identifying interventions to reduce NCDs in workplaces in India: a stakeholder's assessment;examining toxic metals in biological samples and residential PM2.5 to evaluate their risk in adolescent children;ergonomics hazard assessment reduction in large scale petrochemical complex, Vadodara;factors associated with work related quality of life among garment factory employees in South India;factors associated with work related quality of life among garment factory employees in South India;and screening for COVID-19 among workers attending medical examinations under occupational health service of an open cast iron ore mine in Jharkhand: a cross-sectional study.

Impact Short-Long Term Exposure of Air Pollution on Covid-19 Outcome

Introduction: Air pollutant exposure constitutes a serious risk factor for the emergence or aggravation of (existing) pulmonary disease. Aim(s): In this study, we wanted to investigate if recent and chronic exposures to ambient air pollution (AP) is associated with COVID-19 disease severity in a cohort of hospitalized COVID-19 patients. Method(s): 283 COVID-19 patients were recruited at the time of admission to hospital. Several clinical parameters and outcomes were collected from medical records, including the duration of stay, the early-warning score (EWS), oxygen saturation in blood at admission, admission to the intensive care unit (ICU), and clinical improvement at 30 and at 90 days after the day of admission. Daily exposure levels for PM , PM , NO and black carbon (BC) were modeled using a high-resolution spatiotemporal model. Based on daily exposure levels, average exposures 2 days and 1 week before admission and chronic exposure. Result(s): We observed a significant association between the duration of stay and exposure to PM , PM and NO (recent and chronic exposure). For BC, only chronic exposure (CP) was significantly associated with the duration of stay. On average, the duration of stay increased by 1 to 6 days for an inter-quartile range increase in average exposure to AP in the week before admission. CP was associated with 2 to 3 days increased duration of stay. An increase in PM2.5 and PM10 exposure 1 week before admission was associated with higher EWS. Conclusion(s): Exposure to AP was associated with duration of stay and EWS at the time of admission, which implies a potential link between AP exposure and COVID-19 disease severity, and a significant influence of AP exposure on the pressure of care systems.

Characterising SARS-CoV-2 transmission via aerosols and effective sampling methods for surveillance

Background: There is increasing evidence for aerosol-based transmission of SARS-CoV-2, with particulate matter (PM) a possible vector. Air surveillance is necessary to safeguard public spaces. Aim(s): To characterise SARS-CoV-2 distribution in aerosols collected in hospital and public spaces and determine best sampling methods for surveillance. Method(s): Over 8 months in 2021, 8 samplers collected liquid bioaerosols and size-fractioned particulate matter(PM) in hospitals (ICU, Respiratory ward and communal waiting areas), a London railway and underground station, a university, and a primary school. RNA was extracted from samples and RT-qPCR targeting the N-gene of SARSCoV-2 was performed. Samples were cultured on Vero cells. Result(s): 209 air samples were obtained with 20 positive for SARS-CoV-2. 15 positive samples were from hospitals, 10 from outpatient waiting areas (ED waiting area, Chemotherapy Day Unit), 2 of which had the B.1.1.7 mutation (alphavariant) on sequencing, and 5 positive samples from rooms housing SARS-CoV-2 positive patients on ICU and respiratory wards. 5 positive samples were obtained via a portable sampler on two separate journeys in a London underground carriage. SARS-CoV-2 was detected mostly in PM samplers (n=17) compared to liquid bioaerosol samplers (positive sample pick-up 13% vs 4%respectively), in fine particles <=2.5mum(PM2.5) in diameter (n=14). No samples were cultured on Vero cells. Conclusion(s): Size-fractioned particulate matter samplers may be more efficient than liquid bioaerosol samplers in detecting and monitoring SARS-CoV-2 in the air. SARS-CoV-2 is most detected on fine particles, giving support to PM2.5 acting as a vector for aerosol-based transmission.

Varying numbers of acute wheezing cases presenting to paediatric emergency during the COVID-19 pandemic

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.

Interventions for improving indoor and outdoor air quality in and around schools

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

Effects of emission sources on the particle number size distribution of ambient air in the residential area

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

Particle Pollution, increase in Allergy and Asthma cases and application of Nanotechnology

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.

SARS-CoV2 and Air Pollution Interactions: Airborne Transmission and COVID-19

A link between outdoor pollution of particulate matter (PM) and the mortality from COVID-19 disease has been reported. The potential interaction of SARS-CoV2 emitted from an infected subject in the form of droplets or as an aerosol with PM2.5 (PM of 2.5 μm or less in aerodynamic diameter) may modulate SARS-CoV2 replication and infectivity. This may represent an important airborne route of transmission, which could lead to pneumonia and a poor outcome from COVID-19. Further studies are needed to assess the potential infectivity and severity of such transmission.

Spatial Effect of Digital Economy on Particulate Matter 2.5 in the Process of Smart Cities: Evidence from Prefecture-Level Cities in China.

During the COVID-19 pandemic, the digital economy has developed rapidly. The airborne nature of COVID-19 viruses has attracted worldwide attention. Therefore, it is of great significance to analyze the impact of the digital economy on particulate matter 2.5 (PM2.5) emissions. The research sample of this paper include 283 prefecture-level cities in China from 2011 to 2019 in China. Spatial Durbin model was adopted to explore the spatial spillover effect of digital economy on PM2.5 emissions. In addition, considering the impact of smart city pilot (SCP) policy, a spatial difference-in-differences (SDID) model was used to analyze policy effects. The estimation results indicated that (1) the development of the digital economy significantly reduces PM2.5 emissions. (2) The spatial spillover effect of the digital economy significantly reduces PM2.5 emissions in neighboring cities. (3) Smart city construction increases PM2.5 emissions in neighboring cities. (4) The reduction effect of the digital economy on PM2.5 is more pronounced in the sample of eastern cities and urban agglomerations.

Comparative Analysis of Pollutant Levels during Lockdowns Across Different Land-Use over the Emirate of Abu Dhabi, United Arab Emirates

The outbreak of the COVID-19 pandemic has had a significant effect on people all over the world, posing health, economic, and social threats to the entire human population. As a part of preventive measures, at the end of March 2020 the UAE promulgated various lockdown measures to reduce the risk of the pandemic, which have a major impact on its local air quality levels. This research investigates the effect of the lockdown measures on the levels of the air pollutants like NO2 and PM2.5in Abu Dhabi Emirate using air quality stations data for the months of March and April 2020. Overall, NO2 levels have fallen dramatically by a range of 19% to 60% across all land use areas within the Emirate. Conversely, PM2.5 levels varied during the lockdown in April 2020, with increases ranging from 31% to 65% in rural and suburban industrial areas and decreases ranging from 2% to 33% in urban and suburban population areas. It can be observed that the lockdown measures had a huge impact on the NO2 levels due to reduced transportation and human activities while PM2.5 levels displayed great variability. The statistical analysis shows a significant moderate positive relationship (rs 0.476) at 0.05 level between NO2 and traffic volume crossing Musaffah Bridge. © 2021 Geo Publishing, Toronto Canada.

Hesperidin Protects Human HaCaT Keratinocytes from Particulate Matter 2.5-Induced Apoptosis via the Inhibition of Oxidative Stress and Autophagy.

Numerous epidemiological studies have reported that particulate matter 2.5 (PM2.5) causes skin aging and skin inflammation and impairs skin homeostasis. Hesperidin, a bioflavonoid that is abundant in citrus species, reportedly has anti-inflammatory properties. In this study, we evaluated the cytoprotective effect of hesperidin against PM2.5-mediated damage in a human skin cell line (HaCaT). Hesperidin reduced PM2.5-induced intracellular reactive oxygen species (ROS) generation and oxidative cellular/organelle damage. PM2.5 increased the proportion of acridine orange-positive cells, levels of autophagy-related proteins, beclin-1 and microtubule-associated protein light chain 3, and apoptosis-related proteins, B-cell lymphoma-2-associated X protein, cleaved caspase-3, and cleaved caspase-9. However, hesperidin ameliorated PM2.5-induced autophagy and apoptosis. PM2.5 promoted cellular apoptosis via mitogen-activated protein kinase (MAPK) activation by promoting the phosphorylation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38. The MAPK inhibitors U0126, SP600125, and SB203580 along with hesperidin exerted a protective effect against PM2.5-induced cellular apoptosis. Furthermore, hesperidin restored PM2.5-mediated reduction in cell viability via Akt activation; this was also confirmed using LY294002 (a phosphoinositide 3-kinase inhibitor). Overall, hesperidin shows therapeutic potential against PM2.5-induced skin damage by mitigating excessive ROS accumulation, autophagy, and apoptosis.

Influence of COVID 19 in Air Quality Parameters of various Industrials Areas at Jodhpur City

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.

Allergic contact dermatitis caused by elastic bands from FFP2 mask

Background: A 29-year-old woman, with personal history of atopy, presented with face and neck dermatitis lasting 6 months. During the past year, she worked as a nurse in a COVID-19-dedicated ward. The dermatitis had developed since she started using FFP2 masks. She referred using three FFP2 masks, with similar symptoms: 3 M© 9320+, Halyard© Fluidshield N95 and PM 2.5©. She also mentioned history of contact-hypersensitivity reactions to metals, green clothes and leather shoes for several years. Physical examination exhibited erythematous plaques distributed along the contact area of the elastic bands of the FFP2 masks. Patch tests revealed delayed hypersensitivity to the elastic bands 3 M© 9320+ and PM 2.5© (++), mercapto mix (++), 2-mercaptobenzothiazole (MBT) (++), 2-(4-morpholinylmercapto)benzothiazol (MOR) (++), N-cyclohexyl-2-benzothiazolesulfenamide (++), textile dye mix Mx-30 (++), disperse yellow 3 (++), disperse blue 106 (+), potassium dichromate (+), cobalt dichloride (+) and nickel sulfate hexahydrate (+). A latex skin prick test was negative. Allergic contact dermatitis (ACD) caused by elastic bands of FFP2 masks (3 M© 9320+ and PM 2.5 ©) was diagnosed. She was prescribed methylprednisolone aceponate 0.1% cream bid during five days and masks were changed to a type with cotton cloth bands, with resolution of the complaints. ACD to FFP2 masks components in health care workers can be severe, given the prolonged and continuous contact with the source of allergens. The rubber additives thiurams and dithiocarbamates are the main allergen groups involved in ACD to rubber bands in FFP2 masks. This seems to be the first report caused by mercaptobenzothiazole.

ASSOCIATION between the NEIGHBORHOOD BUILT ENVIRONMENT and COVID-19 HOSPITALIZATION

Background: The COVID-19 pandemic has been marked by its disparate impacts on residents in lower income neighborhoods. To better understand reasons for disparities in disease severity, we asked: To what extent does the neighborhood built environment independently predict COVID-19 hospitalizations for people with SARS-CoV-2? Methods: Retrospective analysis of all cases of SARS-CoV-2 diagnosed within the University of Colorado Health and Denver Health healthcare systems from 3/1/2020-12/15/2020. Electronic health records were queried for positive SARS-CoV-2 PCR results for individuals aged ≥18 years during the study period. Demographic and health variables were extracted. Home addresses were matched with social vulnerability indices and built environment variables including population density and crowding, environmental hazards and amenities, and mobility options. Logistic regression was used to identify factors of the neighborhood built environment associated with hospitalization after a positive SARS-CoV-2 result. Results: Among the two systems, 39,304 individuals had positive SARS-CoV-2 tests;14,604 (37.16%) had full demographic data;4,101 (28%) were hospitalized. Odds of hospitalization were higher for individuals living in apartments and in census blocks with lower residential density and higher percentage of multi-family housing units. See Table. Higher particulate matter (PM2.5) levels were associated with higher odds of being hospitalized but living within mile of a highway was not. Living within 1/2 mile of a park and more park acreage in the neighborhood were associated with lower odds of hospitalization. Odds of being hospitalized were higher for individuals in neighborhoods with a lower Walk Score ®, lower Bike Score ®, and higher Transit Score ®. Effects were more pronounced for Latinx individuals. Conclusion: Among those with SARS-CoV-2 infection in Denver, living in areas with high levels of PM2.5, less park access, and lower Walk® and Bike Scores® were found to be independent risk factors for hospitalization when controlling for income and medical comorbidities.

Dynamics of surgical smoke in the operating room during spinal surgery: Comparison of particulate matter 2.5-air concentration between the electric scalpel with and without a smoke evacuation pencil: A cross-sectional study.

BACKGROUND: Surgical smoke is a vaporous by-product generated during tissue incision and cauterization with an electric scalpel. This smoke contains tissue- and blood/vascular-derived substances, bacteria, viruses, and chemical substances. Among them, it contains many fine particles called particulate matter (PM) 2.5, which are harmful and hazardous to the human body. We aimed to investigate the occurrence of PM2.5 in surgical smoke produced during spinal surgery and to evaluate the efficacy of an electric scalpel with a smoke evacuation pencil. METHODS: In this retrospective observational study, 89 patients who underwent spinal surgery between June 2019 and May 2021 were included. A dust monitor was installed in the operating room to measure the PM2.5 air concentration during the surgery. During each surgery, the total amount of PM2.5, the maximum PM2.5 air concentration, the exposure time to PM2.5, and the average value of PM2.5 air concentration from the start to the end of the surgery were calculated. RESULTS: We found that in 29 of the 89 cases (32.6%), the air concentration of PM2.5 increased to a level that could cause health damage during the surgery. Twelve cases (13.4%) reached the level that could cause serious health damage, and 8 cases (9%) reached an emergency warning level. The total amount and the maximum and average levels of PM2.5 were significantly suppressed in the surgery with a smoke evacuation pencil group than in the surgery without a smoke evacuation pencil group. CONCLUSION: We detected hazardous levels of PM2.5 in the air during spinal surgery, highlighting the importance of considering smoke control or reduction during spinal surgery. We recommend using an electric scalpel with a smoke evacuation pencil for regulating PM2.5 levels in the operating room.