Ambient Air Quality Standards Research Articles

Evaluating health risks of PM2.5-bound heavy elements in Faridabad, Haryana (India): an industrial perspective.

The present study isfocused on investigating the heavy/toxic metals (Al, Ni, Cr, Pb, Cu, As,Mn, and Zn) of PM2.5 and assessing their associated human health risks. During the study period (July 2022 to July 2023), the PM2.5 samples were collected from two distinct sites in Faridabad (92 samples from site 1 and 85 samples from site 2). In this study, the US EPA's Risk Assessment Guidance for Superfund (RAGS) was followed to evaluate the human health risk associated with PM2.5-bound heavy elements. The annual average of PM2.5 concentrations was 108 ± 16µgm⁻3 at site 1 and 154 ± 11µgm⁻3 at site 2, approximately three to fourtimes higher than the national ambient air quality standards (annual, 40µgm-3). The analysis of enrichment factors (EFs) for the elements Cr, As, Zn, Cu, Mn, Pb, and Ni indicates that the heavy elements associated with PM2.5 primarily originate from anthropogenic sources. The application of the conditional bivariate probability function (CBPF) model for Faridabad revealed local pollution sources contributing to elevated mass concentrations at the receptor site from the southern (S), northwestern (NW), northeastern (NE), southwestern (SW), and southeastern (SE) regions. Furthermore, positive matrix factorization (PMF) analysis identified the predominant sources of PM2.5-bound heavy elements as industrial emissions (41%), vehicular emissions (34%), and combustion processes (25%). After a thorough assessment of health hazards, Cr appeared as a significant carcinogenic risk factor. Children with elevated hazard quotient (HQ) values for Mn and Cr indicated non-carcinogenic health problems. Ultimately, this analysis reinforces the necessity for rigorous monitoring and intervention to safeguard public health from the potentially harmful effects of heavy elements.

Characteristic of PM2.5 concentration and source apportionment during winter in Seosan, Korea

Seosan is a concentrated industrial complex in the midwestern region of Korea. A study was conducted from December 2020 to January 2021, measuring PM2.5 and chemical components in Seosan using online instruments every hour. The concentration of PM2.5 during the winter season was 31.4±17.8 μg/m3, exceeding the national ambient air quality standard of Korea. The mass fraction of organic matter, elemental carbon, three major ions, five minor ions, crustal elements, and trace elements in PM2.5 accounted for 24.5%, 4.36%, 32.0%, 2.82%, 4.11%, and 5.17% of the total PM2.5 mass concentration, respectively. Source identification was conducted using positive matrix factorization modeling, revealing eight sources of PM2.5: Secondary inorganic aerosol (SIA), vehicle exhaust, industry, coal combustion, biomass burning/incinerator, oil combustion, soil, and aged sea salt. Source contributions varied during high pollution episodes (HPE), with SIA dominating in HPE1 and soil and aged sea salt in HPE2. The potential source contribution function and conditional probability function were utilized to estimate the potential local and regional emission areas for the identified sources. In Seosan, vehicle exhaust and biomass burning/incinerator were primarily influenced by local sources. SIA, industry, and oil combustion sources were significantly affected by short-range transport from eastern China. Soil and aged sea salt, which exhibited high contributions during HPE2, were associated with long-range transport from Inner Mongolia. Coal combustion was attributed to both local sources, particularly large industrial complexes near Seosan, and long-range transport from Northeast China and Inner Mongolia.Graphical

Indoor air quality assessment of an existing apartment located in Indian tropical city, Bhubaneswar

Introduction: A proper investigation on indoor pollution level in economical apartments is important, where the provision for ventilation is limited. A series of experiments were conducted in the houses within an existing economical apartment in Bhubaneswar, India to evaluate various pollutant levels. Materials and methods: Temperature, relative humidity, CO, CO2, Particulate Matter (PM10 and PM2.5), Formaldehyde and Total volatile organic compounds in the bedrooms and kitchens are measured by pollution meters. The experiments were conducted with doors and windows closed conditions. The readings were taken on a four consecutive working day in February 2023 at an interval of 3 h (9:00 am to 9:00 pm). Results: The day wise temperature and humidity variations inside the bedroom and kitchen shows a reverse trend. At the afternoon, the indoor temperature becomes high, while during the night time humidity becomes the highest. The day wise indoor CO2 and CO variation trend is pretty similar. Both CO2 and CO concentrations in bedrooms are the highest in the evening. In contrast to that CO2 and CO concentrations in kitchens becomes maximum during noon time. High particulate matter concentration at outdoor and indoor is observed at the evening time. Higher formaldehyde (HCHO) and Total Volatile Organic Compounds (TVOCs) concentration at the indoor is observed at noon and afternoon time. Conclusion: The results obtained were compared with the recommended values of World Health Organization (WHO) and National Ambient Air Quality Standards (NAQIS). The results revealed that all measured parameters are at a higher level than the recommended values except the indoor CO2 concentrations.

Impacts from air pollution on respiratory disease outcomes: a meta-analysis.

Air pollution is widely acknowledged as a significant factor in respiratory outcomes, including coughing, wheezing, emergency department (ED) visits, and even death. Although several literature reviews have confirmed the association between air pollution and respiratory outcomes, they often did not standardize associations across different studies and overlooked other increasingly impactful pollutants such as trace metals. Recognizing the importance of consistent comparison and emissions of non-exhaust particles from road traffic, this study aims to comprehensively evaluate the standardized effects of various criteria pollutants and trace metals on respiratory health. We conducted a comprehensive meta-analysis of peer-reviewed journal articles on air pollution and respiratory outcomes published between 1 January 2000, and 1 June 2024. The study included children (age < 18 years), adults (age ≥ 18 years), and all age groups exposed to criteria pollutants established by the US Environmental Protection Agency National Ambient Air Quality Standards and over 10 trace metals. Using databases, such as PubMed, MEDLINE, Web of Science Core Collection, and Google Scholar, we identified 579 relevant articles. After rigorous screening and quality assessment using the Newcastle-Ottawa Scale, 50 high-quality studies were included. We converted various reported outcomes (e.g., odds ratios, relative risk, and percent increase) to a standardized odds ratio (OR) for comparability and performed meta-analyses using R 4.4.0 and related packages, ensuring the robustness of our findings. Our meta-analysis indicated significant associations between air pollutants and respiratory outcomes. For particulate matter with diameter ≤ 2.5 μm (PM2.5), the overall ORs for children, adults, and combined age groups were 1.31, 1.10, and 1.26, respectively, indicating a consistent positive association. Similar positive associations were observed for particulate matter with diameter ≤ 10 μm (PM10) and other pollutants, with children showing higher susceptibility than adults. The analysis of trace metals also showed significant associations; however, these findings require cautious interpretation due to the small number of studies. Our study supports associations between air pollutants, including non-exhaust trace metals, and respiratory outcomes across different age groups. The findings underscore the need for stringent environmental health policies and further research, especially in regions with higher pollution levels. The future studies should consider long-term and short-term exposures separately and include diverse populations to improve the accuracy and generalizability of the results.

Simultaneous comparison of the chemical composition and attributable source of PM2.5 during 2014–2018 in major metropolitan cities in South Korea: impacts of policy interventions

Abstract Ambient fine particulate matter (PM2.5) is one of the most concerning pollutants, characterized by its diverse chemical composition. Although various studies have revealed PM2.5 chemical components, there is limited knowledge on how to reduce PM2.5 concentrations through administrative policies focusing on source management. We compared PM2.5 compositional characteristics and performed source apportionment using the positive matrix factorization in four metropolitan cities (Seoul, Daejeon, Gwangju, and Ulsan) in South Korea from 2014 to 2018. The annual average of PM2.5 concentrations exceeded the annual national ambient air quality standard of 15 μg m−3 in all areas while secondary inorganic aerosols constituted the largest fraction of PM2.5. This implies that secondary formation from gaseous precursors in the atmosphere was the main factor contributing to ambient PM2.5. However, the concentrations of PM2.5 constituents varied significantly across cities, suggesting that PM2.5 is a heterogeneous pollutant considerably influenced by region-specific conditions. In line with the chemical composition, secondary nitrate, secondary sulfate, and mobile-related sources were found to be significant contributors of PM2.5. Additionally, the extent of contribution from each source varied across the study regions. We also evaluated the impacts of policy interventions by comparing the PM2.5 composition and source apportionment before and after the policies for improving air quality. Intensive programs focused on the vehicle sector in Seoul led to a considerable decrease in the concentrations of carbonaceous compounds and mobile-related sources. In addition, strengthened regulations on coal-fired power plants (CFPPs) since 2016 have influenced the contributions of coal combustion sources in two cities adjacent to the west coastal area, where approximately half of the CFPPs of the country are densely distributed. Overall, the study’s findings indicate that region-specific PM2.5 chemical constituents and source contributions should be considered for establishing PM2.5-related policies, considering the high heterogeneity of PM2.5.

Characterization and impact of airborne particulate matter over Varanasi: A year-long study on concentration, morphology, and elemental composition

Air pollution is an important worldwide issue, especially pronounced in metropolitan and suburban regions, significantly affecting both public health and surroundings. This study investigates the particles' morphology and elemental analysis in Varanasi, a highly inhabited metropolis in the Indo-Gangetic Plain. The research was conducted over a year, from April 2019 to March 2020, utilizing Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy, Ion Chromatography, and Atomic Absorption Spectroscopy to analyse particulate matter. Results indicated that mean values of PM2.5 and PM10 were 106.5 ± 67.2μg/m³ and 180.8 ± 71.4 μg/m³, respectively. Often, these amounts exceeded the National Ambient Air Quality Standards. SEM-EDX analysis revealed diverse particle morphologies, with significant contributions from both manmade sources including industrial activities and vehicle emissions, and natural sources, like soil dust. Elemental analysis identified major components, including Carbon, Oxygen, Fluorine, Aluminium, and Silicon. IC analysis highlighted dominant ionic species, such as Ca++, SO4−-, NO3−, and Cl−, with monthly variations reflecting different emission sources. Heavy metals concentrations such as Ni, Cd, Cr, Mn, Cu, Pb, Zn, and Fe were quantified, with concentrations varying significantly across months. The findings underscore the complex nature of aerosols in Varanasi and highlight the immediate need for targeted control over air quality measures to minimize the particulate matter's detrimental effects on the local population and ecosystem.

Impact of construction activities on the air quality of Agra city, Uttar Pradesh, India

The current research work was carried out to comprehensively assessed the impact of construction activities on the air quality. Seven sites were chosen along the metro line construction in Agra, Uttar Pradesh, India, to meet the study's goals. The monitoring was performed for 24 hours at each site using the respirable dust sampler (RDS) with a gaseous sampling attachment. The raw data was processed to calculate the Air Quality Index (AQI). The data obtained indicate that all the examined sites had PM10 (particulate matter having the diameter less than or equal to 10 micron) values above the National Ambient Air Quality Standards (NAAQ) values of 100 µg/m3, while SS-05 and SS-06 had PM2.5 (particulate matter having the diameter less than or equal to 2.5 micron) values above the NAAQ values of 60 µg/m3. Values of CO, SO2, and NO2 were discovered to be lower than the NAAQ standard limits. Because PM10's sub index (Si) was found to be the greatest across all locations, it was determined to be the criterion pollutant among all the metrics. Based on the AQI value, the research area's overall air quality was determined to be moderately polluted. At every location, a variety of management techniques, including mist guns, water spraying, and planting, are regularly used to reduce air pollution. Effective implementation of applied air pollution control measures is required to make the air clean and safe for breathing.

Long term analysis of air quality parameters for Ludhiana, India: sources, trends and health impact.

Ludhiana, a pollution hot spot in North India, has seen a rapid deterioration in air quality over the years due to urbanization and industrialization. This study interprets the variations of particulate matter (PM) and gaseous pollutants (Nitrogen oxide, Nitrogen dioxide, NOX, Sulphur dioxide, Carbon monoxide, Benzene, Toluene, Ozone, and Ammonia) for the data observed from 2017 to 2023 in Ludhiana. This also covers the analysis focused on capturing the changes that occurred at the times of lockdown imposed during the Coronavirus Disease (COVID-19). The maximum 24-h averaged mass concentration values exceeded the National Ambient Air Quality Standards (NAAQS) of 100µg/m3 for PM10 concentration and 60µg/m3 for PM2.5 concentration in 2018 by the factor of 5 and 8. With the onset of the COVID-19 lockdown in 2020year, PM10 and PM2.5 reached the minimum level while CO, T, O3, and NO2 increased by the factor of 3.9, 1.9, 1.4, and 1.3 from their previous year. This NO2 is a precursor of ozone formation, a higher NO2 to NO ratio observed during the lockdown, confirms the role of nitrogen compounds in the higher ozone formation rate. Based on the NO2/NO ratio, the probability rate of ozone formation determined using survival analysis is observed to be 94% from 2017 to 2023. The local sources' contribution to these air pollutants during Pre-Lockdown, Lockdown, and Post-Lockdown are analyzed using principal component analysis. The impact of the lockdown on ozone concentration sources has been observed. During the Pre- and Post-Lockdown phases, three sources (PC1, PC2, and PC3) were positively identified. Ozone levels are linked to PC3 in these phases, but during the lockdown, a negative loading in PC3 and positive loadings in PC1 and PC2 indicate a decrease in ozone from reduced emissions and an increase from secondary reactions involving nitrogen compounds. Moreover, the Toluene to Benzene concentration ratio is > 2, indicating the source of their origin from industrial emission or other non-traffic sources. Health assessment for the years 2017-2019 reveals a significant decrease in the number of cases of all-cause mortality, ischemic heart disease, stroke, and chronic obstructive pulmonary disease associated with reducing PM2.5 concentrations to national and international standards.

Emerging Scientific Approaches for Identifying Ecologically Adverse Effects of Air Pollution.

Now more than ever, complex socio-ecological challenges require timely and integrated responses from scientists and policymakers. Air quality is one such challenge. Under the Clean Air Act, the U.S. Environmental Protection Agency establishes ambient air quality standards to protect public welfare from known or anticipated adverse effects of air pollutants. As our understanding of the environment and awareness of social values grow, there is a need to improve characterization of "adversity to the public welfare." Scientific assessment can link ecological effects to public welfare using modern scientific approaches that incorporate ecological complexity and multiple value systems held by the public. We propose ideas for the future of scientific assessments meant to inform air quality and other environmental decision-making, including concrete ways we can focus on vulnerable species and ecosystems, incorporate a multiplicity of values, climate and multiple stressors, and partner to diversify the knowledge upon which protective policies are based.

Study association of urinary Club Cell Protein with air pollution-related pulmonary function compromised among children

BackgroundChildhood exposure to air pollution exacerbates respiratory conditions and even carries deleterious effects on lung functions in adulthood. It is desirable to establish a non-invasive screening test for children to predict early lung insult with air pollution exposure. The association between serum club cell protein (CC16) and obstructive airway diseases is known, but the same is not explored with air-pollution-related lung insult and pulmonary function test (PFT) parameters. AimTo investigate the association between urinary CC16 and PFT parameters in children exposed to differing levels of air pollution. MethodsThis cross-sectional study recruited 107 children from critically-polluted area (CPA) and 96 age-sex-matched children from non-polluted area (NPA). PFT and urinary CC16 were determined with standard techniques. Air quality parameters were estimated with adherence to National Ambient Air Quality Standards (NAAQS). ResultsCPA was observed with 2.5 times poorer Air-Quality-Index compared to NPA. Urinary CC16 levels of children were four-fold higher in CPA compared to NPA (p < 0.001). CPA children were significantly deprived in PFT parameters [FVC(L)-1.86 v/s 2.02, p = 0.01; FEV1(L/s)-1.71 v/s 1.86, p = 0.01 & PEFR(L/s)- 3.25 v/s 3.69, p < 0.001]. While adjusted for physiological parameters, urinary CC16 observed with significant negative association with PFT parameters (FVC: β = −0.02, p=0.03; FEV1: β = −0.03, p=0.001 & FEF25–75 %: β = −0.05, p=0.04). ConclusionThe significant decline in lung function parameters and elevated urinary CC16 levels among children in polluted areas underscore the need for further research to validate urinary CC16 as a reliable screening tool for respiratory health monitoring among children.

Assessment of Ambient Air Pollution Levels: A Five-Year Analysis of PM2.5, NO, NO2, NOX, CO, and SO2

The study conducted on the air quality of five highly polluted cities in India over the last five years (2015-2020) sheds light on the detrimental effects of air pollution and the need for monitoring and mitigation. The research focused on six major air pollutants: PM2.5, NO, NO2, NOX, CO, and SO2. The study's findings reveal that the concentrations of these air pollutants consistently exceeded the limits set by the National Ambient Air Quality Standards 2009 and the World Health Organization's Ambient Air Quality Standards. This indicates that the air quality in these cities was consistently poor and posed a significant health risk to the population. The study emphasises that certain subpopulations, such as the elderly, young children, and individuals with pre-existing health conditions like asthma, are more vulnerable to the harmful effects of air pollutants. Elevated levels of pollutants in the air can lead to severe health effects and contribute to the development of serious diseases. Furthermore, the study highlights that the air quality significantly improved in 2020 due to the nationwide lockdown imposed in response to the COVID-19 pandemic. The restrictions on mobility and industrial activities resulted in reduced emissions, leading to a temporary improvement in air quality. These conclusions underscore the critical importance of understanding the harmful effects of air pollutants and taking measures to protect human health and preserve the quality of the environment.

Correlation of Fine Particulates and Meteorological Parameters in Indoor Public Schools Environment within Benin City, Edo State, Nigeria

This study focused on the correlation of fine particulates and meteorological parameters in indoor public school environments, in Benin City, Edo State, Nigeria. Thirty public schools (17 primary and 13 secondary) were selected for the study. The PM2.5 samples were taken 1.5 – 2.0 meters within the human breathing zone. The sampling was done using an Apex 21 S Casella regular pump with a conical inhalable sampling (CIS) head for eight hours at a flow rate of 3.5L per minute (LPM). The 37-diameter quartz filters were processed in a muffle furnace for four hours at 450 – 500 oC before sampling and weighing afterward. The results obtained showed variations in the meteorological parameters with a range of temperature from 28.52 – 29.82°C. The relative humidity ranged from 84.22 – 427.78%; pressure was 1006.70 - 5052.87 mmHg; wind speed was 4.13 – 1660.88 Km/h and dew point was 24.7 – 3293.56%. The correlation coefficient showed a positive relationship exists in meteorological parameters between primary and secondary schools’ sources of enrichment. The PM2.5 mass concentration had the range of 135 – 785.31 µg/m3 which were above the stationary limits of 25 µg/m3 and 35 µg/m3 stipulated by the National Ambient Air Quality Standards and World Health Organization, respectively. These call for greater attention to alleviate all negative outcomes of environmental health issues.

Study on O3-NOx-VOCscombined air pollution and ozone health effects in the Hexi Corridor.

In order to study the ecological and atmospheric recovery of the Hexi Corridor region, this paper analyzes the migration changes of land use characteristics and utilizes multivariate data and BenMAP-CE software to study the pollution characteristics of ozone and its precursors and the impact on human health in the Hexi Corridor region. The results showed that the increase of cultivated land area in the Hexi Corridor mainly originated from grassland. The MDA8-O3 concentrations met the primary and secondary standards of the Ambient Air Quality Standards on 43% and 99% of the days, respectively. NO2 showed a negative weekend effect with O3, and HCHO was opposite to it. Temperature, barometric pressure, and vegetation were highly correlated with O3-NO2-HCHO. Ozone pollution in the study area caused about 60% of all-cause premature deaths due to cardiovascular diseases. The study suggests that controlling exogenous transport in Wuwei City during the high ozone period (except August) is mainly dominated by the west and northwest, and that synergistic management of VOCs and NOx emissions can reduce O3 pollution and, consequently, reduce the risk to human health.

Assessing Adverse Health Effects of Long-Term Exposure to Low Levels of Ambient Air Pollution: The HEI Experience and What's Next?

Although concentrations of ambient air pollution continue to decline in high-income regions, epidemiological studies document adverse health effects at levels below current standards in many countries. The Health Effects Institute (HEI) recently completed a comprehensive research initiative to investigate the health effects of long-term exposure to low levels of air pollution in the United States (U.S.), Canada, and Europe. We provide an overview and synthesis of the results of this initiative along with other key research, the strengths and limitations of the research, and remaining research needs. The three studies funded through the HEI initiative estimated the effects of long-term ambient exposure to fine particulate matter (PM2.5), nitrogen dioxide, ozone, and other pollutants on a broad range of health outcomes, including cause-specific mortality and cardiovascular and respiratory morbidity. To ensure high quality research and comparability across studies, HEI worked actively with the study teams and engaged independent expert panels for project oversight and review. All three studies documented positive associations between mortality and exposure to PM2.5 below the U.S. National Ambient Air Quality Standards and current and proposed European Union limit values. Furthermore, the studies observed nonthreshold linear (U.S.), or supra-linear (Canada and Europe) exposure-response functions for PM2.5 and mortality. Heterogeneity was found in both the magnitude and shape of this association within and across studies. Strengths of the studies included the large populations (7-69 million), state-of-the-art exposure assessment methods, and thorough statistical analyses that applied novel methods. Future work is needed to better understand potential sources of heterogeneity in the findings across studies and regions. Other areas of future work include the changing and evolving nature of PM components and sources, including wildfires, and the role of indoor environments. This research initiative provided important new evidence of the adverse effects of long-term exposures to low levels of air pollution at and below current standards, suggesting that further reductions could yield larger benefits than previously anticipated.

Drivers of PM2.5 Episodes and Exceedance in India: A Synthesis From the COALESCE Network

AbstractEmission sources influencing high particulate air pollution levels and related mortality in India have been studied earlier on country‐wide and sub‐national scales. Here, we use novel data sets of emissions (for 2019) and observations created under the Carbonaceous Aerosol Emissions, Source Apportionment, and Climate Impacts network in India (Venkataraman et al., 2020, https://doi.org/10.1175/bams‐d‐19‐0030.1) in WRF‐Chem simulations to evaluate drivers of high PM2.5 levels during episodes and in airsheds with different pollution levels. We identify airsheds in “extreme” (110–140 μg/m3), “severe” (80–110 μg/m3) and “significant” (40–80 μg/m3) exceedance of the Indian annual ambient air quality standard (National Ambient Air Quality Standards [NAAQS]) of 40 μg/m3 for PM2.5. We find that primary organic matter and anthropogenic mineral matter (largely coal fly‐ash) drive high PM2.5 levels, both annually and during high PM2.5 episodes. PM2.5 episodes are driven by organic aerosol in north India (Mohali) in wintertime but are additionally influenced by mineral matter and secondary inorganics in central (Bhopal), south India (Mysuru) and eastern India (Shyamnagar). Across airsheds in exceedance of the NAAQS and during high PM2.5 episodes, primary PM2.5 emissions arise largely from the residential sector (50%–75%). Formal sector emissions (industry, thermal power and transport; 40%–55%) drive airshed and episode scale PM2.5 exceedance in northern and eastern India. Agricultural residue burning emissions predominate (50%–75%) on episode scales, both in northern and central India, but not on annual scales. Interestingly, residential sector emissions strongly influence (60%–90%) airsheds in compliance with the NAAQS (annual mean PM2.5 &lt; 40 μg/m3), implying the need for modern residential energy transitions for the reduction of ambient air pollution across India.

Bottom-up assessment of air quality management strategies in Vijayawada, India: Emissions inventory, atmospheric capacity, and policy scenarios

A bottom-up approach evaluates air quality management strategies in Vijayawada, India, a rapidly urbanizing city facing declining air quality. Detailed emission inventories and dispersion modeling assess pollutant concentrations (PM10, PM2.5, SO2, NOx) under various policy scenarios for 2025 and 2030. Business-as-usual (BAU) scenarios reveal the inadequacy of current regulations for PM, SO2, and NOx control. While BS-VI standards effectively reduced NOx emissions from vehicles, overall trends indicate a diminishing atmospheric capacity to assimilate pollutants. Alternative scenarios (ALTs) incorporating sector-specific controls project emission reductions (12–15 % PM10, 19–24 % PM2.5, 24–48 % SO2, 19–32 % NOx) and are expected to maintain pollutant levels below national ambient air quality standards. This integrated approach offers valuable insights for policymakers to develop sustainable air quality strategies aligned with SDGs. The study emphasises the need to consider potential trade-offs between environmental benefits and resource demands, such as increased electricity demand for electric vehicles (SDG 7) and land use competition from urban greening (SDG 11). This study aids in identifying strategies that maximise environmental benefits while minimising trade-offs, fostering sustainable urban development. The research's novelty lies in its integration of scenario-based analysis with atmospheric capacity evaluation, providing a robust framework for air quality management in rapidly urbanising regions.

Spatio-temporal distribution and source contributions of the ambient pollutants in Lucknow city, India.

Clean air is imperative to the survival of all life forms on the planet. However, recent times have witnessed enormous escalation in urban pollution levels. It is therefore, incumbent upon us to decipher measures to deal with it. In perspective, the present study was carried out to assess PM10 and PM2.5 loading, metallic constituents, gaseous pollutants, source contributions, health impact and noise level of nine-locations, grouped as residential, commercial, and industrial in Lucknow city for 2019-21. Mean concentrations during pre-monsoon for PM10, PM2.5, SO2 and NO2 were: 138.2 ± 35.2, 69.1 ± 13.6, 8.5 ± 3.3 and 32.3 ± 7.4µg/m3, respectively, whereas post-monsoon concentrations were 143.0 ± 33.3, 74.6 ± 14.5, 12.5 ± 2.1, and 35.5 ± 6.3µg/m3, respectively. Exceedance percentage of pre-monsoon PM10 over National Ambient Air Quality Standards (NAAQS) was 38.2% while that for post-monsoon was 43.0%; whereas corresponding values for PM2.5 were 15.2% and 24.3%. Post-monsoon season showed higher particulate loading owing to wintertime inversion and high humidity conditions. Order of elements associated with PM2.5 is Co < Cd < Cr < Ni < V < Be < Mo < Mn < Ti < Cu < Pb < Se < Sr < Li < B < As < Ba < Mg < Al < Zn < Ca < Fe < K < Na and that with PM10 is Co < Cd < Ni < Cr < V < Ti < Be < Mo < Cu < Pb < Se < Sr < Li < B < As < Mn < Ba < Mg < Al < Fe < Zn < K < Na < Ca. WHO AIRQ + ascertained 1654, 144 and 1100 attributable cases per 0.1 million of population to PM10 exposure in 2019-21. Source apportionment was carried out using USEPA-PMF and resolved 6 sources with highest percent contributions including road dust re-entrainment, biomass burning and vehicular emission. It is observed that residents of Lucknow city regularly face exposure to particulate pollutants and associated constituents making it imperative to develop pollution abetment strategies.

Unveiling respiratory health risks: PCDD/Fs adhering to particulate matter (PM10 and PM2.5) in Bien Hoa City, Dong Nai, Vietnam

This study investigates the concentrations of atmospheric aerosol particles (PM, including PM2.5 and PM10), as well as the presence and distribution of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in ambient air in Bien Hoa City (Dong Nai province, Vietnam) during the dry and rainy seasons in 2023. The concentrations of 7 PCDDs and 10 PCDFs congeners in PM10 or PM2.5 were determined using gas chromatography-mass spectrometry (GC-MS). The results show that the concentration of PM10 and PM2.5 were 54.7 ± 9.4 µg/m3, 65.3 ± 7.6 µg/m3, and 39.6 ± 7.9 µg/m3, 58.9 ± 12.6 µg/m3, in the rainy season and dry season, respectively. This reveals that while only PM2.5 concentration levels in the dry seasonexceed national ambient air quality standards, but all of PM2.5 concentration levels consistently exceeded WHO guidelines. The study highlights the dominance of PM2.5 and its adverse health implications, as evidenced by the PM2.5/PM10 ratio (0.74 and 0.85 for the rainy and dry seasons, respectively) and its association with worse air quality. Analysis of PCDD/Fs concentrations in PM samples demonstrates their comparable levels in both seasons, with OCDD being the most abundant species. Furthermore, the study estimates the toxic equivalency (TEQ) of PCDD/Fs and assesses health risks, revealing a potentially high cancer risk from exposure to these pollutants, particularly PM2.5 under WHO2005-TEQ. Several PCDD/Fs- WHO2005-TEQ congeners exhibit higher concentration levels in PM2.5 compared to PM10, suggesting differential particulate matter dynamics and potential environmental implications. These findings underscore the urgent need for mitigation strategies to alleviate air pollution and reduce associated health risks in the dioxin hotspot of Vietnam.

Analysis of Sulfur Dioxide (SO2) Exhaust Gas Emission Distribution Patterns from Airport’s Incinerators in East Java

The airport in this study is one of the airports in East Java that uses an incinerator to process its waste. Emissions generated by the incinerator will disperse in the area surrounding one of the airports in East Java. With the increasing interest of the public in air travel, activity at the airport also increases. This increase also impacts the amount of waste processed by the incinerator and the emissions produced, including Sulfur Dioxide (SO2). The aim of this study is to analyze the dispersion of air pollutants using Aermod View modeling software with SO2 parameters from environmental document data of the airport from January to June and from July to December generated by the incinerator stack. The model produces isopleths representing the dispersion of SO2 emissions. The results of the SO2 model still meet ambient air quality standards, as indicated in Appendix VII of Government Regulation Number 22 of 2021.

Model misspecification, measurement error, and apparent supralinearity in the concentration-response relationship between PM2.5 and mortality.

A growing number of studies have produced results that suggest the shape of the concentration-response (C-R) relationship between PM2.5 exposure and mortality is "supralinear" such that incremental risk is higher at the lowest exposure levels than at the highest exposure levels. If the C-R function is in fact supralinear, then there may be significant health benefits associated with reductions in PM2.5 below the current US National Ambient Air Quality Standards (NAAQS), as each incremental tightening of the PM2.5 NAAQS would be expected to produce ever-greater reductions in mortality risk. In this paper we undertake a series of tests with simulated cohort data to examine whether there are alternative explanations for apparent supralinearity in PM2.5 C-R functions. Our results show that a linear C-R function for PM2.5 can falsely appear to be supralinear in a statistical estimation process for a variety of reasons, such as spatial variation in the composition of total PM2.5 mass, the presence of confounders that are correlated with PM2.5 exposure, and some types of measurement error in estimates of PM2.5 exposure. To the best of our knowledge, this is the first simulation-based study to examine alternative explanations for apparent supralinearity in C-R functions.