Air

The vehicle in-cabin is subject to several types of pollutants infiltrating from the outdoors or emitted directly inside it, such as Volatile Organic Compounds (VOCs). The concentration of TVOC (total volatile organic compounds) is the result of the emission from different equipment surfaces that compose the car cabin. In the present study, the experimental characterization of TVOC emission from the interior surfaces of a car cabin is discussed by considering the influence of two parameters: the temperature and ventilation modes. A measurement location grid was used to measure TVOC’s emissions from 267 points on all surfaces of the car’s interior equipment. Three different temperatures and two ventilation modes (recirculation and outdoor air) were investigated. The results indicate that the concentration of TVOC increases with the temperature inside the cabin with a contribution that varies with the type of cabin equipment including the dashboard, center console, seats, and carpets. On the other hand, the concentration distributions of TVOC showed relative differences of 10–13% and 2–5% for surface and volumetric measurements, respectively. This implies no preferential positioning of the in-cabin probe for TVOC volumetric concentration measurements. In addition, the recirculation ventilation mode results in a higher accumulation of TVOC; therefore, higher concentrations are measured. Full article

Ethylene oxide (EtO) is a colorless, flammable gas at room temperature produced by the catalytic oxidation of ethylene. EtO is widely used by medical sterilization facilities to clean medical supplies and equipment. Recent epidemiological studies showed that EtO is a more potent carcinogen than previously documented, leading the Environmental Protection Agency (EPA) to update, in December 2016, the inhalation unit risk estimate for EtO. This resulted in the identification of EtO as a potential health concern in several areas across the US, including the state of Utah. The geography surrounding Salt Lake Valley creates a bowl, which is ideal for collecting air pollution emissions. The region often experiences inversion episodes which inhibit vertical mixing and cause an accumulation of air pollutants, leading to unhealthy pollution levels. Using the EPA’s dispersion modeling software, AERMOD, this study estimated EtO concentrations through facility stack and fugitive emissions modeling results. These values were compared with those of canister-based concentrations from ambient air samples taken near a medical device sterilization facility in Salt Lake Valley. Stainless steel whole-air passivated canisters were used to collect 24 h ambient concentration samples of EtO. Eight locations surrounding a Salt Lake Valley medical device sterilization facility and four background sites were chosen to measure the ambient concentrations. Accounting for potential atmospheric impacts on EtO, measurements were sampled in winter 2022 (January–March) and summer 2022 (July–September). The modeled EtO concentrations were adjusted to account for background values associated with the winter or summer data. Then, the two methodologies were compared using a Wilcoxon signed-ranked paired test. The statistical analysis resulted in six of the eight sample locations surrounding the sterilization facility being significantly different when comparing the canister-based measurements of ambient EtO to modeled estimates. Canister-based measurements taken at sites one, three, and four were statistically greater than the modeled estimates, while sites two, five, and seven were statistically less than the modeled estimates. Also, the summer background value calculated was almost 2.5 times greater than the winter one. The results do not suggest whether one method is more or less conservative than the other. In conclusion, the five of the closest sites and site seven were statistically different when comparing measured and modeled ambient concentrations of EtO. The comparison results do not clearly indicate if a correction factor could be derived for future human exposure to cancer risk assessment modeling. However, it is reasonable that the closer to the sterilization facility, the more total EtO exposure will be realized. Full article

In this work, the catalytic performance of clinoptilolite (CLIN) and SBA-15 catalysts, doped with Fe and Cu, was evaluated in the selective catalytic reduction of NO using NH₃ as a reducing agent (SCR-NH₃). Both Cu-CLIN and Fe-CLIN were obtained by ion-exchange using natural clinoptilolite zeolite originating from the Hrabovec deposit (northeast Slovakia region). Cu-SBA-15 and Fe-SBA-15 were prepared by impregnation into SBA-15 mesoporous synthesized silica. Standard catalytic activity tests were carried out on a bench-scale laboratory apparatus using a reaction mixture of a standard test. GHSV of 48,000 h⁻¹ was adopted based on the space velocity of a real NH₃-SCR catalyst for diesel vehicles (100–550 °C). All Cu-doped samples showed better NO conversion values than Fe-doped samples. Clinoptilolite catalysts were more active than those based on SBA-15. Maximum NO conversions of about 96% were observed for Cu-CLIN and Fe-CLIN at 350–400 °C, respectively. Moreover, Fe-CLIN also showed higher stability in the presence of SO₂ and water steam at 350 °C. These results demonstrate the potential of metal-doped natural clinoptilolite to be used as cost-effective catalysts applied to the abatement of NOx emissions generated in automotive combustion processes. Full article

One of people’s greatest concerns about air quality degradation is its impact on human health. This work is a case study that aims to investigate the air quality and the related impact on people’s health in a coastal city over the eastern Mediterranean. The analysis proceeded during a low-tourist density period, covering the days from 17 to 27 November 2022. Hourly ${\mathrm{PM}}_{2.5}$, ${\mathrm{NO}}_2$ and ${\mathrm{O}}_3$ concentration records from three, mobile, Air Quality Monitoring Systems (AQMS), established in an urban location, port and central area of Rhodes city, are analyzed. To investigate the impact of pollution levels on human health, the Air Quality Health Index (AQHI) is calculated. The daily and diurnal variation of pollutants’ concentration and AQHI among the different areas, as well as the relation among the ambient air pollutants and AQHI, are studied. Additionally, to investigate the impact of wind regime on the variation of pollution and AQHI levels, the hourly zonal and meridional wind-speed components, as well as the temperature at 2 m, the dew point temperature at 2 m, and the height of the boundary layer from ERA5 reanalysis, are retrieved for the region of the southeastern Mediterranean. Results show that the highest pollution level occurs in the city center of Rhodes, compared to the rest of the studied locations. In general, the findings do not show exceedances of the pollutants’ concentration according to the European Directive 2008/50/EC. Moreover, findings show that in some cases, the health risk is classified from Low to Moderate in terms of AQHI. The analysis indicates that the climate conditions affect the pollutants’ concentration due to dispersion, and likely, the atmospheric transport of pollutants. Finally, this work aims to improve the knowledge regarding the air quality of southeastern Greece, promoting the framework for the green and sustainable development of the South Aegean Sea. Full article

The increasing population and its associated amenities demand innovative devices, infrastructure, methods, plans and policies. Regional climate has a great role in deciding the air quality and energy demand, and therefore, weather and climate have an indisputable role in its consumption and storage. Here, we present the changes in trace gases and associated regional weather in India during lockdown and unlock periods of COVID-19. We observe a reduction of about 30% in sulphur dioxide (SO₂) and 10–20% in aerosols in the Indo-Gangetic Plain (IGP), large cities, industrial sites, mining areas and thermal power plants during lockdown as compared to the same period in the previous year and with respect to its climatology. However, a considerable increase in aerosols is found, particularly over IGP during Unlock 1.0 (1–30 June 2020), because of the relaxation of lockdown restrictions. The analyses also show a decrease in temperature by 1–3 °C during lockdown compared to its climatology for the same period, mainly in IGP and Central India, possibly due to the significant reduction in absorbing aerosols such as black carbon and decrease in humidity during the period. The west coast, northwest and central India show reduced wind speed when compared to its previous year and climatological values, suggesting that there was a change in regional weather due to the lockdown. Energy demand in India decreased by about 25–30% during the first phase of lockdown and about 20% during the complete lockdown period. This study thus suggests that the reduction of pollution could also modify local weather, and these results would be useful for drafting policy decisions on air pollution reduction, urban development, the energy sector, agriculture and water resources. Full article

This article is a case study of museum premises at the Museum of King John III’s Palace at Wilanow (Warsaw, Poland), wetted as a result of a failure of the water supply system to the air conditioning unit located in the attic of the building. As a result of flooding, discoloration and cracks appeared on the plaster and stucco decoration of the ceiling, located mainly in the central part of the ceiling of the King’s Library. The paintings (plafonds) mounted on the ceiling of this room also became damp. The article analyzes the microbiological contamination of air and damp paintings in the context of promptly proceeding with the drying of damp building partitions. The obtained results of microbiological air pollution in the flooded rooms were significantly lower than the permissible values recommended by Interdepartmental Commission for Maximum Admissible Concentrations and Intensities for Agents Harmful to Health in the Working Environment. In the King’s Library, i.e., the room with the dampest plaster and stucco as a result of the accident, the concentration of mold spores in the air was only 15 cfu/m³. This means that the immediate commencement of intensive drying of the building partitions (walls, ceilings with wooden floors) brought very good results. The rapid reduction in the moisture of the building partitions contributed to the worsening conditions for the development of microorganisms, which can have an adverse effect on wooden building partitions, plaster, stucco, etc. Full article

Air pollution is a major public health concern. The region of South Texas in the United States has experienced high levels of air pollution in recent years due to an increase in population, cross-border trade between the U.S.A. and Mexico, and high vehicular activity. This review assesses the relationships between human health and air pollution in South Texas. A thorough scientific search was performed using PubMed, Science Direct, and ProQuest, with most of the literature focusing on the source apportionment of particulate matter that is 2.5 microns or less in width (PM_2.5), Carbon Dioxide (CO₂), carbon monoxide (CO), Black Carbon (BC), and associated health risks for children and pregnant women. Findings from the source apportionment studies suggest the role of industries, automobiles emissions, agricultural burning, construction work, and unpaved roads in the overall deterioration of air quality and deleterious health effects, such as respiratory and cardiovascular diseases. This review demonstrates the pressing need for more air pollution and health effects studies in this region, especially the Brownsville–Harlingen–McAllen metropolitan area. Full article

The greatest challenge of the coming century will be the consequences of an imbalanced atmosphere. Currently, projections of global heating due to an increasingly imbalanced atmosphere are dire, but they underestimate the near-term heating impacts of the growing concentrations of methane. Industrially mediated carbon capture and storage sometimes gets raised as a promising solution on the CO₂ front, but it is presently commercially inviable. Despite these facts, we nonetheless need to act globally to reduce the atmospheric concentrations of greenhouse gases, although our increasingly separate information ecosystems make finding a way to express the reality of the atmospheric imbalance crisis to a wide audience daunting. One approach to presenting the atmospheric imbalances leading to global heating is to strip the discussion down initially to its bare bones with a sharp focus on the variables of the logistic growth equation. Although virtually anything can be politicized, the logistic growth equation’s variables are at least apolitical in their origin. After examining those variables, we can proceed to focus on density-dependent mortality factors (DDMFs) and their relationship to visible climatic changes driven by atmospheric imbalances. Both the Global North and the Global South need to do all that we do to reduce atmospheric greenhouse gas accumulation, reducing DDMFs, while paying careful attention to Indigenous rights and to the need for global gender equity, so that our efforts to control DDMFs do not produce a new expression of colonialism. Full article

Fluorine (F) produced from the fertilizer factory occurs in the process of phosphate fertilizer production, using sulfur and phosphate rocks as raw materials. Technologies to control atmospheric pollution with F should be adopted to reduce the impact on agricultural production. This study has the hypothesis that the emission of F, derived from the chimneys of fertilizer factories, is influencing the quality of corn (Zea mays L.) and increasing the F levels in the soil and plants. The objective of the study was to monitor the contents of F in corn leaves and soil in properties located close to the fertilizer production industry (between 1.5 and 2.0 km) before and after the installation of scrubber filters in the chimneys of the factory. A field study was carried out during the 2020/2021 harvest to evaluate the contents of F in corn plants and soil. Results showed that the scrubber filter installation represented a F reduction average of 92% in leaves comparing the average before the scrubber filter installation. Corn showed symptoms of F toxicity, such as leaf chlorosis, caused by the disintegration of chloroplasts, inhibition of photosynthesis, and others. In addition, there was a reduction of 40% (from the first to the second collecting) and 75% (from the first to the third collecting) in the levels of F in the soil after the scrubber filter installation. Based on the results, we conclude that the implementation of a scrubber filter is an optimal alternative to reduce F levels in corn leaves and the soil in properties located close to a fertilizer factory. Full article

Urban air and soil quality has been deteriorating during the past few years due to urbanization, industrialization and increased number of vehicles. The goal of the current study was to assess the Air Pollution Tolerance Index (APTI) and heavy metal absorption (Pb, Cd, Zn, and Ni) potential by ten selected trees planted along the roadside in the metropolitan city of Lahore, Pakistan. APTI was estimated on the basis of biochemical parameters (chlorophyll content, ascorbic acid, pH and relative water contents) of plant extract, while heavy metals (HMs) accumulation potential was measured by a digestion method. The highest APTI was estimated in P. longifolia (78.9), followed by A. scholarils (75.9) and M. indica (71.9). Overall, these three species have significant closeness among the higher pollution-tolerance results. The poor APTI result was determined in F. religiosa (19.5) and E. citriodora (14.9). The highest Pb contents were observed in P. longifolia and M. indica i.e., 135 and 132 mg/kg, respectively. Similarly, the highest Zn contents were found in P. longifolia and S. cumini with 130 and 132 mg/kg, respectively. The Ni concentration was observed highest in P. longifolia (34 mg/kg), but in the remaining species, it is almost the same trend of Ni accumulation. Combining these trees can be useful for fostering green-belt growth along roadsides to reduce air and soil pollution and achieve environmental sustainability. But unfortunately, these species are not planted well across the roadside as they have very little biodiversity index, as compared to other species. These species should be planted in urban areas to enhance biodiversity in the urban ecosystem and make them sustainable cities and communities. Full article

Ammonia (NH₃) is a naturally occurring, highly reactive and soluble alkaline trace gas, originating from both natural and anthropogenic sources. It is present throughout the biosphere, yet plays a complicated role in atmospheric acid–base reactions resulting in the formation of inorganic secondary inorganic aerosols (SIAs). While the general mechanisms are recognised, factors controlling the reactions leading to SIA formation are less explored. This review summarises the current knowledge of NH₃ sources, emission and deposition processes and atmospheric reactions leading to the formation of SIA. Brief summaries of NH₃ and SIA long-range transport and trans-boundary pollution, a discussion of precursor species to SIAs (other than NH₃), abiotic and biotic controls and state-of-the-art methods of measurement and modelling of pollutants are also included. In Ireland, NH₃ concentrations remained below National and European Union limits, until 2016 when a rise in emissions was seen due to agricultural expansion. However, due to a lack of continuous monitoring, source and receptor relationships are difficult to establish, including the appointment of precursor gases and aerosols to source regions and industries. Additionally, the lack of continuous monitoring leads to over- and underestimations of precursor gases present, resulting in inaccuracies of the estimated importance of NH₃ as a precursor gas for SIA. These gaps in data can hinder the accuracy and precision of forecasting models. Deposition measurements and the modelling of NH₃ present another challenge. Direct source measurements are required for the parameterization of bi-directional fluxes; however, high-quality data inputs can be limited by local micrometeorological conditions, or the types of instrumentation used. Long-term measurements remain challenging for both aerosols and precursor gases over larger areas or arduous terrains. Full article

Non-Road Mobile Machinery (NRMM) incorporate a wide range of machinery, with or without bodywork and wheels, and are installed with a combustion engine and not intended for carrying passengers or goods on the road. These are used in many different sectors including construction, agriculture, forestry, mining, local authorities, airport and port ground operations, railways, inland waterways and within the household and gardening sector. This article presents a review of the state of knowledge with regard to non-road mobile machinery, particularly focusing on their regulation and the atmospheric emissions associated with them. This was undertaken as there is currently a lack of this information available in the literature, which is an oversight due to the potential for Non-Road Mobile Machinery to form a greater part of atmospheric emissions in the future, as other areas of emissions are tackled by regulations, as is outlined in the article. Emissions such as particulate matter (PM), carbon oxide (CO), carbon dioxide (CO₂), hydrocarbons (HC), nitrogen oxides (NO_x) and sulphur oxides (SO_x) from NRMM contribute considerably to total emissions released into the air. NRMM are diverse in application, engine type and fuel use, and are therefore difficult to categorise. This leads to numerous issues when it comes to the control and regulation of their emissions. The most recent European and international regulations are outlined in this article. Due to the divergent nature of NRMM, their emissions profiles are highly varied, and in-use emissions monitoring is challenging. This has led to a lack of data and inaccuracies in the estimation of total emissions and emission inventories. It was assumed in the past that emissions from non-road sources did not contribute as significantly to total emissions as those from on-road sources. This assumption was partly due to the difficulty in gathering relevant data, and it was disproven in the 1990s by studies in The Netherlands, Finland and Sweden. It is now understood that NRMM will eventually surpass on-road vehicles as the leading source of mobile pollution due to the continuing efforts to reduce emissions from other sources. Many states worldwide gather emissions data from NRMM, and EU member states are required to report their emissions. As of January 2017, a new European regulation establishing limits for gaseous and particulate pollutants from NRMM applies, and this regulation also defines administrative and technical requirements for EU approval. The exact number of NRMM and the total amount of fuel they use is currently not known. In Ireland, for example, their fuel use has been reported under stationary boilers and engines. However, this results in the underestimation of emissions of some pollutants (NO_x in particular) because emissions of air pollutants tend to be higher in mobile than in stationary machinery. Full article

Fine particulate matter (PM2.5) from fireworks displays have been linked to serious health concerns, particularly in infants and children. Outdoor displays in large, recurring festivals such as state fairs thus may threaten local air quality, particularly given the proximity of fairgrounds to substantial, nearby residential populations. Here, we identify state fairs with known firework displays and assess their impact on air quality in nearby communities. We assessed the impact of three large, recurring festivals on PM2.5 levels in nearby communities. Overall, our multi-year analysis failed to identify measurable increases in PM2.5 concentrations during festival days at air quality monitoring sites within 4–10 km of the fairgrounds, even when data were filtered by wind direction. Results suggest that firework displays from such festivals are unlikely to violate PM2.5 air quality standards in communities near the fairgrounds. The results suggest that identifying a potential air pollution signal associated with fireworks is challenging, particularly in urban fairgrounds where air quality is impacted by multiple local and distant pollution sources. Local impacts may yet be identified in future studies if air quality is monitored closer to the fairgrounds and if the fireworks pyrotechnic content is known. Full article