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The mean mass concentrations of black carbon (BC), biomass burning (BC)bb, and fossil fuel combustion (BC)ff have been estimated during March–May 2020 (during the COVID-19 outbreak) and March–May 2019 at a semiarid region of Agra over the Indo-Gangetic basin region. The daily mean mass concentration of BC in 2020 and 2019 was 3.9 and 6.9 µg m−3, respectively. The high monthly mean mass concentration of BC was found to be 4.7, 3.4 and 3.3 µg m−3 in Mar-2020, Apr-2020, and May-2020, respectively, whereas in Mar-2019, Apr-2019, and May-2019 was 7.7, 7.5 and 5.4 µg m−3, respectively. The absorption coefficient (babs) and absorption angstrom exponent (AAE) of black carbon were calculated. The highest mean AAE was 1.6 in the year 2020 (Mar–May 2020) indicating the dominance of biomass burning. The mean mass concentration of fossil fuel (BC)ff and biomass burning (BC)bb is 3.4 and 0.51 µg m−3, respectively, in 2020 whereas 6.4 and 0.73 µg m−3, respectively, in 2019. The mean fraction contribution of BC with fossil fuel (BC)ff was 82.1 ± 13.5% and biomass burning (BC)bb was 17.9 ± 4.3% in 2020, while in 2019, fossil fuel (BC)ff was 86.7 ± 13.5% and biomass burning (BC)bb was 13.3 ± 6.7%. The population-weighted mean concentration of BC, fossil fuel (BC)ff, and biomass burning (BC)bb has been calculated. The health risk assessment of BC has been analyzed in the form of attributable relative risk factors and attributed relative risk during the COVID-19 outbreak using AirQ + v.2.0 model. The attributable relative risk factors of BC were 20.6% in 2020 and 29.4% in 2019. The mean attributed relative risk per 10,000,000 populations at 95% confidence interval (CI) due to BC was 184.06 (142.6–225.2) in 2020 and 609.06 (418.3–714.6) in 2019. The low attributed factor and attributed relative risk in 2020 may be attributed to improvements in air quality and a fall in the emission of BC. In 2020, due to the COVID-19 pandemic, the whole country faced the biggest lockdown, ban of the transportation of private vehicles, trains, aircraft, and construction activities, and shut down of the industry leading to a fall in the impact of BC on human health. Overall, this was like a blessing in disguise. This study will help in future planning of mitigation and emission control of air pollutants in large and BC in particular. It only needs a multipronged approach. This study may be like torch bearing to set path for mitigation of impacts of air pollution and improvement of air quality. [ABSTRACT FROM AUTHOR]

This study enhances the understanding of the particulate matters (PM2.5 and PM10) and their physical and chemical behavior over the Taj Mahal, Agra, in North-Central India. The mass concentration was determined, and the shape and size of the particles and chemical characterizations have been carried out using SEM–EDX. The high level and significant variation of PM10 (162.2 µg m−3) and PM2.5 (83.9 µg m−3) were observed. The exceedance factor of the present study region is in critical and moderate condition. Morphological characterization reveals the particles of different shapes and sizes, while elemental analysis shows the presence of Si, Al, Fe, Ca, K, Cl, Mg, Na, Cu, and Zn. The dominance of Si indicated the contribution of natural sources, i.e., soil over this region. Three significant sources, viz. soil/road paved dust/vegetative emissions, vehicular/industrial emissions, and intermingling of dust and combustion particles, have been identified using principal component analysis over North-Central India. Health risk analysis of particulate matter identified carcinogenic and non-carcinogenic metals in the present study, which comes in contact with human beings during inhalation. The non-carcinogenic risk was much higher than the acceptable level. The high carcinogenic risks were found in Zn in PM10 and Cu in PM2.5 for both children and adults. [ABSTRACT FROM AUTHOR]

Increasing anthropogenic alteration has resulted in increased exposure to both point and nonpoint source pollution. These exposures are increasingly studied for their role in human diseases, including diseases with known genetic or lifestyle risk factors. This study analyzed associations between a variety of human diseases and trace metals, PCBs, and PAHs in soil, groundwater, sediment, and fish. Contaminant spatial data at the county level from Virginia were used in ArcGIS to identify these associations among socially vulnerable populations. The neurologic and psychiatric disorders and cognitive markers were associated with numerous metals in groundwater/soil and/or aquatic system contaminants. Cancer death rates, fetal deaths, and infant deaths were also related to multiple environmental exposures from both categories of exposure. In contrast, many of the chronic diseases which are primarily attributed to lifestyle showed little association with these exposures with the exception of COPD which did appear to be associated with multiple metal exposures. Asthma showed similar associations compared to COPD. Our data suggest that within the context of socially vulnerable populations, where disease burden is often highest, exposures to metals, PAHs, and PCBs may play a role in the development or exacerbation of several highly prevalent categories of disease. These environmental exposures likely act through a variety of pathways all generally leading to increased oxidative stress, inflammation, or interference with biological systems and a subsequent role in disease development. [ABSTRACT FROM AUTHOR]