Stubble Burning and its Impact on Air Quality in Delhi NCT: A Case Study

Stubble burning is now considered to be one of the major activities affecting air quality because it is one of the major sources of aerosol as well as gaseous pollution. There are two main reasons for biomass burning, first one is that there is a very short window of time between the harvesting and the wheat sowing of the wheat. The second being, removing the paddy residue that has remained on the field is a time-consuming job. The time period from harvesting to sowing being very low and the labor is either very expensive or unavailable this leads to the only easiest option that the farmer has i.e. burning the residue right on the field after harvest so that the farmers can quickly prepare the land for the next sowing. This method is very cheap and takes less time that’s why farmers use this method. For this specific reason with the onset of winter, stubble fires become rampant in north India. Stubble-burning emissions contain toxic chemicals which cause respiratory problems as well as diseases. The paper aims to examine the environmental impacts associated with stubble burning over the NCT of Delhi. The paper performs both qualitative and quantitative analysis on the statistical data pertaining to crop burning. The monthly variation for particulate matter (PM10 and PM2.5) and trace gases (NOx, CO, and SO2) during the stubble burning period (Sep-Nov) has also been studied and analyzed for 5 years (2015-19), and a noticeable increase in pollutant levels.

Alterations by Air Pollution in Inflammation and Metals in Pleural Effusion of Pneumonia Patients

Air pollution is known to increase the risk of pneumonia. However, the effects of air pollution on the pleural effusion of patients with pneumonia are unclear. The objective of this study was to investigate alterations in inflammatory–immune biomarkers by air pollution in patients with pneumonia by analyzing their pleural effusion. Patients who had undergone thoracentesis to drain their pleural effusion in a hospital were recruited for this study. Patients with pneumonia and those with congestive heart failure respectively served as the case and control groups. We observed that an increase of 1 ppb in one-year NO2 was associated with a decrease of 0.105 ng/mL in cluster of differentiation 62 (CD62) (95% confidence interval (CI) = −0.085, −0.004, p < 0.05) in the pleural effusion. Furthermore, we observed that an increase in one−year 1 ppb of NO2 was associated with a decrease of 0.026 ng/mL in molybdenum (Mo) (95% CI = −0.138, −0.020, p < 0.05). An increase in one-year 1 ppb of SO2 was associated with a decrease of 0.531 ng/mL in zinc (95% CI = −0.164, −0.006, p < 0.05). Also, an increase in one-year 1 ppb of O3 was associated with a decrease of 0.025 ng/mL in Mo (95% CI = −0.372, −0.053, p < 0.05). In conclusion, air pollution exposure, especially gaseous pollution, may be associated with the regulation of immune responses and changes in metal levels in the pleural effusion of pneumonia patients.

Ozone modification as an efficient strategy for promoting the photocatalytic effect of TiO2 for air purification

A “two-bird-with-one-stone” strategy by ozone modification on TiO2 provides an approach to address the gaseous pollution with ozone and VOCs.

Assessment of exposure risk from hidden fungal growth by measurements of air change rates in construction cavities and living areas

The transfer of particulate and gaseous pollution from hidden fungi growing on non-visible surfaces within the building envelope to occupied rooms is limited by the separating structure. Yet, growth, even in sealed construction cavities, is known to cause annoying smells and other more adverse health symptoms among the building occupants. This study analyses limitations of air change rate measurements in inaccessible construction cavities as well as analyses of the air exchange between living areas and accessible cavities such as crawl spaces and attics. It was necessary to invent a field study technique to use the tracer gas decay method in small and inaccessible cavities. This technique allowed further investigation on the exposure risk from hidden fungal growth. Assessment of the air transfer between crawl spaces and living areas indicate that the tightness of separating structure has an influence on the exposure risk.