Effect of exposure to PM10 on child health: evidence based on a large-scale survey from 184 cities in India

Exploring the link between particulate matter pollution and acute respiratory infection risk in children using generalized estimating equations analysis: a robust statistical approach

BACKGROUND

India is facing a burdensome public health challenge due to air pollution, with a particularly high burden of acute respiratory infections (ARI) among children. To address this issue, our study aims to evaluate the association between exposure to fine particulate matter (PM2.5) and ARI incidence in young children in India.

MATERIALS AND METHODS

Our study used PM2.5 data provided by the Atmospheric Composition Analysis Group at Washington University to assess the association between PM2.5 exposure and ARI incidence in 223,375 children sampled from the 2019-2021 Demographic Health Survey in India. We employed the generalized estimating equation and reported odds ratios and 95% confidence intervals for a 10 µg/m3 increase in PM2.5 and quartiles of PM2.5 exposure.

RESULTS

Each 10 µg/m3 increase in PM2.5 levels was associated with an increased odds of ARI (OR: 1.23, 95% CI: 1.19-1.27). A change from the first quartile of PM2.5 (2.5-34.4 µg/m3) to the second quartile (34.5-51.5 µg/m3) of PM2.5 was associated with a two-fold change (OR: 2.06, 95% CI: 1.60-2.66) in the odds of developing ARI. Similarly, comparing the first quartile to the fourth quartile of PM2.5 exposure (78.3-128.9 µg/m3) resulted in an over four-fold increase in the odds of ARI (OR: 4.45, 95% CI: 3.37-5.87).

CONCLUSION

Mitigation efforts must be continued implementing higher restrictions in India and to bring new interventions to ensure safe levels of air for reducing the burden of disease and mortality associated with air pollution in India.

Differential impact of maternal education on under-five mortality in rural and urban India

Under-five mortality rate (U5MR) differs by rural-urban place of residence and mother's education; however, the rural-urban gap in U5MR by mother's educational attainment is unclear in the existing literature. Using five rounds of the national family health surveys (NFHS I-V) conducted between 1992-93 and 2019-21 in India, this study estimated the main and interaction effects of rural-urban and maternal education on U5MR. The mixed effect Cox proportional hazard (MECPH) model was used to predict the risk of under-five mortality (U5M). The finding shows that unadjusted U5MR remained 50 per cent higher in rural areas than in urban areas across the surveys. Whereas, after controlling for demographic, socioeconomic, and maternal health care predictors of U5M, the MECPH regression results indicated that urban children had a higher risk of death than their rural counterparts in NFHS I-III. However, there are no significant rural-urban differences in the last two surveys (NFHS IV -V). In addition, increasing maternal education levels were associated with lower U5M in all surveys. Though, in recent years, primary education has had no significant effect. The U5M risk was additionally lower for urban children than rural children whose mothers had secondary and higher education by NFHS-III; however, this additional urban advantage was no longer significant in recent surveys. The higher impact of secondary education on U5MR in urban areas in the past may be attributed to poor socio-economic, healthcare conditions in rural areas. Overall, maternal education, particularly secondary education, remained a protective factor for U5M in both rural and urban areas, even after controlling for predictors. Therefore, there is a need to increase the focus on secondary education for girls for a further decline in U5M.

Health risk assessment for particulate matter: application of AirQ+ model in the northern Caribbean region of Colombia

Air pollution is considered the world's most important environmental and public health risk. The annual exposure for particulate matter (PM) in the northern Caribbean region of Colombia between 2011 and 2019 was determined using PM records from 25 monitoring stations located within the area. The impact of exposure to particulate matter was assessed through the updated Global Burden of Disease health risk functions using the AirQ+ model for mortality attributable to acute lower respiratory disease (in children ≤ 4 years); mortality in adults aged > 18 years old attributable to chronic obstructive pulmonary disease, ischaemic heart disease, lung cancer, and stroke; and all-cause post-neonatal infant mortality. The proportions of the prevalence of bronchitis in children and the incidence of chronic bronchitis in adults attributable to PM exposure were also estimated for the population at risk. Weather Research and Forecasting-California PUFF (WRF-CALPUFF) modeling systems were used to estimate the spatiotemporal trends and calculate mortality relative risk due to prolonged PM_2.5 exposure. Proportions of mortality attributable to long-term exposure to PM_2.5 were estimated to be around 11.6% of ALRI deaths in children ≤ 4 years of age, 16.1% for COPD, and 26.6% for IHD in adults. For LC and stroke, annual proportions attributable to PM exposure were estimated to be 9.1% and 18.9%, respectively. An estimated 738 deaths per year are directly attributed to particulate matter pollution. The highest number of deaths per year is recorded in the adult population over 18 years old with a mean of 401 events. The mean risk in terms of the prevalence of bronchitis attributable to air pollution in children was determined to be 109 per 100,000 inhabitants per year. The maximum RR values for mortality (up 1.95%) from long-term PM_2.5 exposure were predicted to correspond to regions downwind to the industrial zone.

Supplementary information

The online version contains supplementary material available at 10.1007/s11869-023-01304-5.

Impact of Air Pollution on Child Health in India and the Way Forward

Recent research in epidemiological modelling reveals that air pollution affects child health in various ways resulting in low birthweight, stillbirth, preterm birth, developmental delay, growth failure, poor respiratory and cardiovascular health, and a higher risk of anemia. India has embarked on the national clean air program, but a much stronger coordinated multi-sectoral approach is required to minimize the child health burden caused by air pollution. Air pollution should be treated as a public health crisis that can only be managed with policy backed by science, gradual transition to clean energy use, emission reduction supported by clean air technologies, long-term commitment from the Government, and cooperation of the citizens.

Exposure to fine particulate matter and acute upper- and lower-respiratory tract infections (AURI and ALRI) in children under five years of age in India

As one of the world's polluted regions, we assessed the association between ambient PM_2.5 levels and acute lower and upper respiratory infection in India. We assessed 55,118 children from the 2015-2016 Demographic Health Survey in India using the information on levels of PM_2.5 in 2015 and 2016 from the Atmospheric Composition Analysis Group. We used the generalized estimating equation for the analysis reported as odds ratios and 95% confidence intervals for every 10 µg/m³ increase and quartiles in PM_2.5. Every 10 µg/m³ increase in levels of PM_2.5 associated with acute upper respiratory infection (OR 1.02, 95%CI: 1.02-1.03) and acute lower respiratory infection (OR 1.05, 95%CI: 1.03-1.06). This association was confirmed by quartile exposure assessments. Mitigation efforts must be continued implementing higher restrictions in India to ensure safe levels of air.