Association between changes in air quality and hospital admissions during the holi festival

Human health impacts attributable to inhalation exposure of particulate matter (PM10 and PM2.5) during the Holi festival

OBJECTIVE

The present study focuses on residential areas of Delhi to identify the elevated levels of ambient PM10 and PM2.5 due to biomass burning followed by the coloring activity in the Holi festival celebrated at the end of the winter season. This study also focuses on the health risk assessment and mortality among different age groups due to the change in particulate matter levels during the Holi festival in Delhi, India.

MATERIALS AND METHODS

Secondary data of particulate matters have been procured from the Central Pollution Control Board (CPCB), Delhi Pollution Control Committee (DPCC), and Indian Institute of Tropical Meteorology (IITM), Pune for the period of the pre-, during, and post-Holi period for the year 2018-2020 at four selected residential locations in Delhi, India. The health impacts of particle inhalation were quantified using the AirQ + models.

RESULTS

The results indicated the levels of PM10 and PM2.5 rise about 3-4 times higher during the Holi festival than on normal days, resulting in health risks and causing an excess number of mortality and Asthma cases in Delhi. Such cases were also found to be higher in 2018, followed by 2019 and 2020 at all the selected locations in Delhi.

CONCLUSIONS

The study linked the increasing particulate levels in the Holi festival with the increased health risk through short-term exposure of the population. The excess number of cases (ENCs) of mortality, all causes of mortality among adults (age > 30 years) associated with short-term exposure to particulate were also identified.

Assessment of interrelationship between meteorology, air quality and COVID 19 cases in Gujarat state

In the present study, pollutants levels from March 1, 2020, to August 30, 2020, were compared with similar periods of 2019 to assess the impact of lockdown due to COVID 19 on the quality of air in 3 different cities of Gujarat, India named Ahmedabad, Gandhinagar, and Valsad. Data was collected from AccuWeather and Central Pollution Control Board website for study period. Data was analyzed by comparing air quality taking 2019 as reference and correlation matrix were developed for study sites. Lockdown resulted from COVID-19 has shown decline trends in pollutant concentration resulting in improved air quality in the study area. In the first city Ahmedabad, Gujarat an air pollutant parameter such as CO, PM_2.5, PM_10, NO₂, and SO₂ were reduced by 54%, 181%, 70%, 33%, and 103% respectively. Almost similar trends were observed in the rest of the two cities also i.e., Gandhinagar and Valsad. NO₂ level got reduced by a factor of 100% which can be associated with ban on vehicular movement. Correlation between the air pollutant and metrological variables with COVID-19 variables were also studied be developing correlation matrix. In Gandhinagar, a strong correlation was observed between carbon monoxide, and PM₁₀ with COVID-19, a moderate correlation between NO₂, and SO₂ with the COVID-19 variables, a week correlation was found between temperature and COVID-19, and no correlation is found between wind speed and COVID-19 variables.

Health risk assessment of PM2.5 on walking trips

PM_2.5 has an impact on residents' physical health during travelling, especially walking completely exposed to the environment. In order to obtain the specific impact of PM_2.5 on walking, 368 healthy volunteers were selected and they were grouped according to gender and age. In the experiment, the heart rate change rate (HR%) is taken as test variable. According to receiver operating characteristic (ROC) curve, the travel is divided into two states: safety and risk. Based on this, a binary logit model considering Body Mass Index (BMI) is established to determine the contribution of PM_2.5 concentration and body characteristics to travel risk. The experiment was conducted on Chang'an Middle Road in Xi'an City. The analysis results show that the threshold of HR% for safety and risk ranges from 31.1 to 40.1%, and that of PM_2.5 concentration ranges from 81 to 168 μg/m³. The probability of risk rises 5.8% and 11.4%, respectively, for every unit increase in PM_2.5 concentration and HR%. Under same conditions, the probability of risk for male is 76.8% of that for female. The probability of risk for youth is 67.5% of that for middle-aged people, and the probability of risk for people with BMI in healthy range is 72.1% of that for non-healthy range. The research evaluates risk characteristics of walking in particular polluted weather, which can improve residents' health level and provide suggestions for travel decision while walking.

Health Effects of Air-Quality Regulations in Seoul Metropolitan Area: Applying Synthetic Control Method to Controlled-Interrupted Time-Series Analysis

Despite enormous investment in air-quality regulations, there are only a few studies about the health effects of the air-quality regulations. By applying synthetic control methods to controlled-interrupted time-series analysis, this study aimed to test whether air-quality regulations implemented in Seoul metropolitan area since 2005 had reduced cardiovascular mortality rate in Seoul and Incheon. Each synthetic control for Seoul and Incheon was constructed to predict the counterfactual cardiovascular mortality rate through synthetic control methods. By using a synthetic control as a control group in controlled-interrupted time-series analysis, we tested whether the air-quality regulations had changed the trend of cardiovascular mortality rate in Seoul and Incheon after the intervention. The results showed a significant slope change in cardiovascular mortality rate in Seoul (coefficient: −0.001, 95% confidence interval (CI): −0.0015, −0.0004) and Incheon (coefficient: −0.0006, 95% CI: −0.0012, 0). This study suggests additional evidence that air-quality regulations implemented in the Seoul metropolitan areas since 2005 had beneficial effects on cardiovascular mortality rate in Seoul and Incheon.