Impact of COVID-19 Pandemic Constraints on the Ecobiochemical Status of Cultivated Soils along Transportation Routes.

There is a lack of studies on the impact of COVID-19-related population mobility and freight transport restrictions on the soil environment. The purpose of this study was to evaluate the impact of automotive pollution on selected parameters describing the quality and healthiness of crop soils based on results obtained before the pandemic (2017-2019) in relation to data from the pandemic period (2020-2021). The study included soils from six cultivated fields located in eastern Poland along national roads (DK No. 74 and 82) and provincial roads (DW No. 761 and 835). Soil samples were taken from distances of 5, 20, 50, and 100 m from the edge of the roadway. The following soil characteristics were determined: pHKCl, content of total organic carbon (TOC), total nitrogen (TN), and activity of the three enzymes dehydrogenases (ADh), neutral phosphatase (APh), and urease (AU). The degree of traffic-generated soil pollution was assessed by determining the samples' total cadmium and lead levels (Cd and Pb) and total content of 14 polycyclic aromatic hydrocarbons (Σ14PAHs). The monitoring of cultivated soils showed that the parameters of cultivated soils varied primarily according to the distance from the edge of the roadway. There was an increase in soil acidity and TOC and TN content and a decrease in Cd, Pb, and Σ14PAHs as one moved away from the edge of the roadway. The highest ADh and APh values were found in soils located 100 m from the edge of the road. AU at 5 m and 20 m from the edge of the pavement was significantly higher than at 100 m away. The reduction in vehicular traffic associated with the pandemic did not affect the changes in the reaction of the studied soils and their TOC, TN, and Pb contents. The lowest content of Σ14PAHs was found in 2020. In the case of the amount of Cd in soils, a downward effect was also observed in 2020. However, no significant differences were noted, except for the soils in Skorzeszyce and Luszczów Kolonia. The reduced influx of xenobiotics into the soil environment stimulated ADh and APh. In the following year (2021), the amounts of tested xenobiotics and enzyme activities in the soils were at a similar level to those in 2019. The results indicate a positive but short-term effect of the pandemic on reducing the contamination of soils located along transportation routes.

Early Clinical Development of Lufotrelvir as a Potential Therapy for COVID-19

Lufotrelvir was designed as a first in class 3CL protease inhibitor to treat COVID-19. Development of lufotrelvir was challenged by its relatively poor stability due to its propensity to epimerize and degrade. Key elements of process development included improvement of the supply routes to the indole and lactam fragments, a Claisen addition to homologate the lactam, and a subsequent phosphorylation reaction to prepare the prodrug as well as identification of a DMSO solvated form of lufotrelvir to enable long-term storage. As a new approach to preparing the indole fragment, a Cu-catalyzed C-O coupling using oxalamide ligands was demonstrated. The control of process-related impurities was essential to accommodate the parenteral formulation. Isolation of an MEK solvate followed by the DMSO solvate ensured that all impurities were controlled appropriately. © 2023 American Chemical Society.

Preface

We are pleased to provide you with the proceedings of 2022 4th International Conference on Resources and Environment Sciences (ICRES 2022).The conference was expected to be held during June 10-12, 2022 in Bangkok, Thailand, while the situation of COVID-19 pandemic is unpredictable and unstable. Most of conference participants could not travel to attend the conference venue to do oral presentations. Taking all conditions into consideration, conference committee decided to change physical conference into virtual conference. It was held online by ZOOM application successfully during the same date.The conference was highlighted by four outstanding Keynote Speakers and two invited speakers. Keynote speakers include Prof. Kaimin Shih, The University of Hong Kong, China with his topic "Metal Stabilization and Resource Recovery Examples in Urban Environment”;Prof. Nur Islami, University of Riau, Indonesia who presented a talk on "An Valuable Approach to Study Groundwater Contamination in a Shallow Aquifer System”;Prof. Danny Sutanto, University of Wollongong, Australia who shared a speech on "Solid-State Transformer for Smart Power Grid Applications”;Assoc. Prof. Phebe Ding, Universiti Putra Malaysia, Malaysia who presented a talk about "Role of Postharvest Technology in Producing Quality Fresh Horticultural Produces”. Additionally, two excellent invited speakers, Assoc. Prof. Chunrong Jia from University of Memphis, Tennessee, USA with speech title "Apportioning variability of polycyclic aromatic hydrocarbons (PAHs) in the ambient air in the Memphis Tri-State Area, USA”, and Assoc. Prof. Farhad Shahnia from Murdoch University, Australia with speech title "Recent and Future Research on Microgrid Clusters”.Each normal oral presenter had about 12 Minutes of Presentation and 3 Minutes of Question and Answer. Conference was organized in 5 sessions with various topics: Environmental Management, Waste Utilization and Sustainable Development, Wastewater Treatment, Water Analysis and Hydraulic Engineering, Renewable Energy Technology, Chemical Engineering and Fluid Mechanics, Resources and Environmental Science & Sustainable Development, Energy and Chemical Engineering.All accepted papers presented at the ICRES 2022 were included in this volume, which contained three chapters with topics: (1) Environmental Pollution and Control (2) Waste Management and Utilization (3) Clean Energy and Technology. All papers were subjected to peer-review by conference committee members and international reviewers. The papers were selected based on high quality and high relevancy to the conference scope.We would like to express our sincere gratitude to organizing committee and the volunteers who have dedicated their time and efforts in planning, promoting, and helping the conference. We hope that the readers would gain some valuable knowledge from this effort.List of Committees, Statement of Peer Review are available in this Pdf.

Live to die another day: novel insights may explain the pathophysiology behind smoker's paradox in SARS-CoV-2 infection.

The severe acute respiratory coronavirus 2 (SARS-CoV-2) infection demonstrates a highly variable and unpredictable course. Several reports have claimed a smoker's paradox in coronavirus disease 2019 (COVID-19), in line with previous suggestions that smoking is associated with better survival after acute myocardial infarction and appears protective in preeclampsia. Several plausible physiological explanations exist accounting for the paradoxical observation of smoking engendering protection against SARS-CoV-2 infection. In this review, we delineate novel mechanisms whereby smoking habits and smokers' genetic polymorphism status affecting various nitric oxide (NO) pathways (endothelial NO synthase, cytochrome P450 (CYP450), erythropoietin receptor (EPOR); ß-common receptor (ßcR)), along with tobacco smoke modulation of microRNA-155 and aryl-hydrocarbon receptor (AHR) effects, may be important determinators of SARS-CoV-2 infection and COVID-19 course. While transient NO bioavailability increase and beneficial immunoregulatory modulations through the above-mentioned pathways using exogenous, endogenous, genetic and/or therapeutic modalities may have direct and specific, viricidal SARS-CoV-2 effects, employing tobacco smoke inhalation to achieve protection equals self-harm. Tobacco smoking remains the leading cause of death, illness, and impoverishment.

Benzo[a]pyrene-Environmental Occurrence, Human Exposure, and Mechanisms of Toxicity.

Benzo[a]pyrene (B[a]P) is the main representative of polycyclic aromatic hydrocarbons (PAHs), and has been repeatedly found in the air, surface water, soil, and sediments. It is present in cigarette smoke as well as in food products, especially when smoked and grilled. Human exposure to B[a]P is therefore common. Research shows growing evidence concerning toxic effects induced by this substance. This xenobiotic is metabolized by cytochrome P450 (CYP P450) to carcinogenic metabolite: 7ß,8α-dihydroxy-9α,10α-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE), which creates DNA adducts, causing mutations and malignant transformations. Moreover, B[a]P is epigenotoxic, neurotoxic, and teratogenic, and exhibits pro-oxidative potential and causes impairment of animals' fertility. CYP P450 is strongly involved in B[a]P metabolism, and it is simultaneously expressed as a result of the association of B[a]P with aromatic hydrocarbon receptor (AhR), playing an essential role in the cancerogenic potential of various xenobiotics. In turn, polymorphism of CYP P450 genes determines the sensitivity of the organism to B[a]P. It was also observed that B[a]P facilitates the multiplication of viruses, which may be an additional problem with the widespread COVID-19 pandemic. Based on publications mainly from 2017 to 2022, this paper presents the occurrence of B[a]P in various environmental compartments and human surroundings, shows the exposure of humans to this substance, and describes the mechanisms of its toxicity.

Study of PM2.5-bound polycyclic aromatic hydrocarbons and anhydro-sugars in ambient air near two Spanish oil refineries: Covid-19 effects

We report the results from a 12 month-long study of the organic compounds associated to PM2.5 samples collected around two petroleum refineries (4 samples/month/site) in two complex industrial zones reporting atmospheric pollution issues in the past (Estuary of Huelva and Bay of Algeciras, Spain). Sampling campaign was done from March 2020 when a Covid-19 lockdown was established at Spain to March 2021. Concentrations of fine particulate polycyclic aromatic hydrocarbons (PAHs) and anhydrosugars were separately measured using gas chromatography-mass spectrometry (GC-MS) and ion chromatography-amperometric detection (IC-PAD). The annual average abundances of PM2.5-bound benzo[a]pyrene (BaP) are 0.024 and 0.013 ng˖m−3 at La Rábida and Puente Mayorga monitoring stations, while both sites have annual average concentrations of levoglucosan in PM2.5 of 14.98 and 9.78 ng˖m−3, respectively. Seasonal variations are observed for concentrations of ƩPAHs and total anhydrosugars in both sampling sites. For PAHs, the highest concentrations averaging c. a. 0.400 (La Rábida) and 0.350 ng m−3 (Puente Mayorga) are reported in cold months during December 2020-Febraury 2021 (post-lockdown period), compared to the lowest levels averaging 0.111 and 0.211 ng˖m−3, respectively, in temperate months from mid-March 2020 to early June 2020 (0.284 and 0.321 ng m−3 on average annually), coinciding with the confinement and relaxation periods in Spain. Similarly, total anhydrosugars show the highest values of 81.80 ng˖m−3 (La Rábida) and 53.52 ng˖m−3 (Puente Mayorga) in winter and lowest values of 2.71 ng˖m−3 and 3.30 ng˖m−3 into the lockdown period (22.51 and 14.09 ng˖m−3 on average annually). Except phenanthrene, PAHs are present in PM2.5 principally as result of motor vehicle exhausts. Levoglucosan, a tracer for biomass burning, peaked in December 2020 and January 2021, during the high residential wood-burning season. In addition, multivariate analysis was used to assess the origin of organic components of PM2.5 samples. The two principal components are characterized by the grouping of heavy PAHs associated to vehicular traffic, and anhydrosugars indicating biomass burning emissions, respectively.

Abundance, Source Apportionment and Health Risk Assessment of Polycyclic Aromatic Hydrocarbons and Nitro-Polycyclic Aromatic Hydrocarbons in PM2.5 in the Urban Atmosphere of Singapore

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.

Preface to EREE 2022

The 2022 International Conference on Environment, Resources and Energy Engineering (EREE2022) was scheduled to be held in Bangkok, Thailand, however, due to unexpected global surge in COVID-19 variant in the last three months, for safety and also travel restriction reasons, the conference was held virtually via “Zoom”.Delegates from around the world including Thailand, Bulgaria, Ecuador, Indonesia, Cambodia, Chile, Philippines and Sri Lanka took the opportunity to share their research results and discuss potential scientific and engineering development from their work that contributed to the success of the conference.All papers in these proceedings have passed the vigorous review process involving reviewers of the International Technical Committee. Authors benefited from valuable comments and improved their submissions to the satisfaction of reviewers. The virtual presentation serves as another opportunity for the conference delegates to address critiques in the real time online meetings with the expert audience.There were four keynote speakers and two invited speakers who gave talks covering different areas of the conference. The keynote speakers are (i) Prof Kaimin Shih (The University of Hong Kong, China) who gave a talk on on “Metal Stabilization and Resource Recovery Examples in Urban Environment”, (ii) Prof. Nur Islami (University of Riau, Indonesia) who gave a talk on “A Valuable Approach to Study Groundwater Contamination in a Shallow Aquifer System”, (iii) Prof Danny Sutanto (University of Wollongong, Australia) who gave a talk on “Solid State Transformer for Smart Power Grid Applications”, and (iv) Prof Phebe Ding (Universiti Putra Malaysia, Malaysia) who gave a talk on ”Role of Postharvest Technology in Producing Quality Fresh Horticultural Products.”. The invited speakers are (i) Assoc. Prof Chunrong Jia (University of Memphis, Tennessee, USA) who gave a talk on “Apportioning variability of polycyclic aromatic hydrocarbon (PAHs) in the ambient air in the Memphis Tri-State Area, USA”, and (ii) Assoc. Prof Farhad Shania (Murdoch University, Australia) who gave a talk on “Recent and Future Research in Microgrid Cluster”.The proceedings record papers presented during the conference, all of them have been divided into 3 sessions in the proceedings: Session 1-Resource & Environment Management and Sustainable Development, Session 2-Energy Chemistry and Chemical Engineering, and Session 3 Renewable Energy Technology and Energy Consumption Analysis.The variety of research topics presented in the conference and novelty exhibited in the papers published in the proceedings once again demonstrated the value of EREE2022.On behalf of the conference committee, I would like to thank the Technical Program Committee members, the Conference Program Coordinator, the keynote speakers and all participants, whose papers are presented in the conference proceedings, all contributing to the success of the conference.List of Conference Committees are available in this Pdf.

Plasmonic nanobiosensors for detection of different targets

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.

Seasonal variation, sources, and risk assessment of PM2.5-bound PAHs in Nantong, China: A pre- and post-COVID-19 case study

Between 2018 and 2022, a total of 231 PM2.5 samples were collected in Nantong, China, and analyzed online for 16 US EPA PAHs utilizing a variety of analytical methodologies, including high-performance liquid chromatography data analysis, principal component analysis, and characteristic ratio analysis. The seasonal variation and pollution characteristics of 16 PAHs in PM2.5 over a long period in Nantong, China, were analyzed, and correlations and traceability changes with a variety of emission sources were established. Additionally, health assessment models for BaP equivalent concentration, daily exposure dose, lifetime excess risk of cancer, and life expectancy loss were constructed for various ages and genders. The results indicated that the total number of days with BaP concentrations less than the national limit standard of 1.0 ng/m(3) was 60.17% (139/231), with rates of 25.40%, 35.71%, and 94.05% from 2019 to 2021, respectively;the total concentration range of 16 PAHs demonstrated a downward trend, but pollution was relatively severe in winter. The seasonal variation showed winter > autumn > spring > summer. The detection rates of 4 and 5 rings were generally high and fluctuated between dropping and increasing. Principal factor analysis and characteristic ratio traceability analysis indicated that PAH pollution is primarily caused by local coal-fired sources and traffic emissions, with a new trend of biomass combustion. Furthermore, BaP remains the primary contributor to carcinogenic factors, and the health risk is higher in females than in males, and in adults than in children. A low level of PAHs in the air may have health benefits. Traffic control and flow restrictions, as well as production restrictions, are all part of Nantong's COVID-19 pandemic prevention and control policies. These policies contributed to PAH risk prevention and control, as well as pollution reduction.

Health effects and known pathology associated with the use of E-cigarettes.

In recent years, new nicotine delivery methods have emerged, and many users are choosing electronic cigarettes (e-cigarettes) over traditional tobacco cigarettes. E-cigarette use is very popular among adolescents, with more than 3.5 million currently using these products in the US. Despite the increased prevalence of e-cigarette use, there is limited knowledge regarding the health impact of e-cigarettes on the general population. Based on published findings by others, E-cigarette is associated with lung injury outbreak, which increased health and safety concerns related to consuming this product. Different components of e-cigarettes, including food-safe liquid solvents and flavorings, can cause health issues related to pneumonia, pulmonary injury, and bronchiolitis. In addition, e-cigarettes contain alarmingly high levels of carcinogens and toxicants that may have long-lasting effects on other organ systems, including the development of neurological manifestations, lung cancer, cardiovascular disorders, and tooth decay. Despite the well- documented potential for harm, e-cigarettes do not appear to increase susceptibility to SARS-CoV- 2 infection. Furthermore, some studies have found that e-cigarette users experience improvements in lung health and minimal adverse effects. Therefore, more studies are needed to provide a definitive conclusion on the long-term safety of e-cigarettes. The purpose of this review is to inform the readers about the possible health-risks associated with the use of e-cigarettes, especially among the group of young and young-adults, from a molecular biology point of view.

Polycyclic aromatic hydrocarbons (PAHs) exposure through cooking environment and assessment strategies for human health implications

The polycyclic aromatic hydrocarbons' (PAHs) exposure through day to day cooking activities has been a serious concern for human health due to their carcinogenic nature. Given the Covid-19 conditions, where people are spending extended time indoors, the likely exposure to these compounds will increase for the members involved/not involved in cooking. In this context, this review summarizes different studies undertaken worldwide on PAHs from cooking activities, the sources of exposure (fumes/emissions, dust/depositions), effect of scale (households/restaurants/neighborhoods) of cooking, monitoring process, risk assessment (air sampling and urinary metabolites), global distribution pattern. Proportionately higher number of studies was focused on cooking fumes and emissions while very limited studies aimed at kitchen depositions and dust. Most of the studies have not reported the size of particulate matter considered for determining PAHs exposure from cooking fumes and emissions. The evaluation of reported data becomes more complicated due to difference in sampling and expression units, the number and types of PAHs (parent, oxygenated-PAHs, i.e., o-PAHs, nitro-PAHs, i.e., n-PAHs) studied/found, lack of other intrinsic information (site and control parameters), lack of specific regulations etc. Therefore, such studies require method standardization for future policy development. This review also highlights the gaps and challenges in existing knowledge and future prospects.

Photoelectric and diffusion charging measurements of fine particulate air pollution along the main roads of the city of Madrid from 1999 to 2021

In this work, the evolution of the fine particulate air pollution (of size below one μm) produced by the vehicles when driving along several roads of Madrid is studied. Measurements were taken with portable near real-time sensors of Diffusion Charging (DC) and Photoelectric Charging (PC) while driving along the roads. The obtained measurement profiles basically consist of spikes when measuring in the exhaust plumes of preceding vehicles and a background level of mixed aged exhaust that forms when high traffic intensity exist. The DC sensor measures air concentration of the particles Total Active Surface (TAS) and the PC sensor was calibrated to measure the air concentration of Particle bound Polycyclic Aromatic Hydrocarbons (PPAH). The amount of adsorbed PAH per active surface (the PC/DC ratio) is a measure of particles toxicity. Both sensors are sensible to ultra-fine particles of size below 0.1 μm. The measured median values of DC and PC, for the years 1999, 2001, 2005, 2006, 2016, 2017, 2020 and 2021, are plotted as well as their median PC/DC ratio. Examples of measurement profiles are also shown including measurements during COVID-19 driving restrictions. During these restrictions, we could conclude that our measured particulate air pollution of fine and ultrafine particles is caused by "polluting-vehicles" still coexisting in the vehicle fleet of Madrid, which do not fulfill the latest Euro standard because they are too old or have no/malfunctioning catalytic converter and/or diesel particle filter (DPF). The changes of the measured median of the DC and PC values are discussed based on already known results of implemented vehicle technologies for reducing emissions, the evolution of the vehicle fleet fulfilling the increasingly demanding Euro standards, the traffic count, the PC and DC working principles, the evolution of the exhaust emission when exiting the pipe, and on the sulfur content reductions in diesel. The main factors that allowed the large reduction of the median values of both DC and PC (from 1167 ± 57 mm2/m3 and 990 ± 54 ng/m3 in 1999 to 263 ± 14 mm2/m3 and 124 ± 7 ng/m3 in 2021 respectively) as well as the changes in the PC/DC ratio was, according to our findings, the diesel sulfur content reduction and the implementation of the Diesel Oxidation Catalysis (DOC) and the DPF. • Decrease in the total active surface of fine particles in the air of the city of Madrid since 1999. • Decrease in PAH adsorbed on fine particles in the air along the roads of the city of Madrid since 1999. • Evolution of on-road fine and ultrafine exhaust particle emissions in Madrid since 1999. • Drastic localized increase of air suspended fine particles caused by specific polluting vehicles. • Changes in the on-road fine and ultrafine exhaust particles toxicity in Madrid since 1999. [ FROM AUTHOR] Copyright of Atmospheric Environment is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

Real-time Monitoring of Bioaerosol in a Residential Property in Central Tokyo

Real-time onsite monitoring of indoor airborne microbes in a residential property in central Tokyo was carried out in 2020 and 2021, following the onset of the COVID-19 pandemic. A microbial sensor utilizing fluorescence emitted by microorganisms was used to measure bioaerosol concentrations in the living room and children's bedroom as well as on the balcony. Indoor PM2.5 was also monitored simultaneously at certain time points using a PM2.5 sensor. The behavior of the residents was also recorded during some monitoring periods. The average number concentration of microbes as fungi in the living room was 15,100, 58,800, and 10,600 counts m(-3) in spring, summer, and winter, respectively, increasing in summer when the outside temperature was high. Microbial number concentrations were closely related to human behavior, increasing rapidly during periods of physical activity, but decreasing again within 20-30 min of the activity ending. There was no clear correlation between indoor microbial number concentrations and PM2.5 concentrations, suggesting that indoor microorganisms are concentrated in coarse particles, such as dust, which are quickly removed via gravitational settling. The concentration of indoor airborne microorganisms decreased significantly after ventilation, and although an occasional increase was observed immediately after ventilation, concentrations decreased again rapidly within 10-20 min. These results suggest that even a short period of ventilation can significantly reduce the indoor bioaerosol.

On the Flip Side of Mask Wearing: Increased Exposure to Volatile Organic Compounds and a Risk-Reducing Solution.

Surgical masks have been worn by the public worldwide during the COVID-19 pandemic, yet hazardous chemicals in the petroleum-derived polymer layer of masks are currently ignored and unregulated. These organic compounds pose potential health risks to the mask wearer through dermal contact or inhalation. Here, we show that surgical masks from around the world are loaded with semivolatile and volatile organic compounds (VOCs), including alkanes, polycyclic aromatic hydrocarbons (PAHs), phthalate esters, and reactive carbonyls at ng to µg/mask levels. Naphthalene was the most abundant mask-borne PAH, accounting for over 80% of total PAH levels; acrolein, a mutagenic carbonyl, was detected in most of the mask samples, and di(2-ethylhexyl) phthalate, an androgen antagonist, was detected in one-third of the samples. Furthermore, there is large mask-to-mask variability of the residue VOCs, revealing the uneven quality of masks. We confirm that masks containing more residue VOCs lead to significantly higher exposure levels and associated disease risks to the wearer, which should warrant the attention of the general public and regulatory agencies. We find that heating the masks at 50 °C for as short as 60 min lowers the total VOC content by up to 80%, providing a simple method to limit our exposure to mask-borne VOCs.

Polycyclic aromatic hydrocarbons and nitro-polycyclic aromatic hydrocarbons in five East Asian cities: Seasonal characteristics, health risks, and yearly variations.

Total suspended particulate matter and fine particulate matter were collected in five East Asian cities (Sapporo, Sagamihara, Kirishima, Shenyang, and Vladivostok) during warm and cold periods from 2017 to 2018. Nine polycyclic aromatic hydrocarbons (PAHs) and three nitro-polycyclic aromatic hydrocarbons (NPAHs) were detected by high-performance liquid chromatography with a fluorescence detector. The average concentrations of ∑PAHs and ∑NPAHs differed significantly both temporally and spatially and were the lowest in Kirishima during the warm period (∑PAHs: 0.11 ± 0.06 ng m-3; ∑NPAHs: 1.23 ± 0.96 pg m-3) and the highest in Shenyang during the cold period (∑PAHs: 49.7 ± 21.8 ng m-3; ∑NPAHs: 357 ± 180 pg m-3). The average total benzo[a]pyrene-equivalent concentrations were also higher in Shenyang and Vladivostok than in Japanese cities. According to the results of source apportionment, traffic emissions impacted these cities in both the warm and cold periods, whereas coal combustion-generated effects were obvious in Shenyang and Vladivostok during the cold period. Furthermore, PAHs and NPAHs originating from the Asian continent, including Shenyang and Vladivostok, exerted some influence on Japanese cities, especially in the cold period. Compared to Japanese cities and Vladivostok, yearly variations in ∑PAHs and 1-nitropyrene in Shenyang showed that their concentrations were considerably lower than those reported in past studies, indicating the positive effects of air pollutant control policies in China. These results not only describe the current characteristics and yearly variations of PAHs and NPAHs in typical urban cities in East Asia but also, more importantly, reveal that the effects of the East Asian monsoon play an important role in the analysis of atmospheric behaviours of PAHs and NPAHs. Furthermore, this study supports the role of multinational cooperation to promote air pollution control in East Asia.

Air pollution and indoor settings.

Indoor environments contribute significantly to total human exposure to air pollutants, as people spend most of their time indoors. Household air pollution (HAP) resulting from cooking with polluting ("dirty") fuels, which include coal, kerosene, and biomass (wood, charcoal, crop residues, and animal manure) is a global environmental health problem. Indoor pollutants are gases, particulates, toxins, and microorganisms among others, that can have an impact especially on the health of children and adults through a combination of different mechanisms on oxidative stress and gene activation, epigenetic, cellular, and immunological systems. Air pollution is a major risk factor and contributor to morbidity and mortality from major chronic diseases. Children are significantly affected by the impact of the environment due to biological immaturity, prenatal and postnatal lung development. Poor air quality has been related to an increased prevalence of clinical manifestations of allergic asthma and rhinitis. Health professionals should increase their role in managing the exposure of children and adults to air pollution with better methods of care, prevention, and collective action. Interventions to reduce household pollutants may promote health and can be achieved with education, community, and health professional involvement.