Daily nonaccidental mortality associated with short-term PM2.5 exposures in Delhi, India

Abstract

Background: 

Ambient particulate matter of aerodynamic diameter less than 2.5 microns PM2.5) levels in Delhi routinely exceed World Health Organization (WHO) guidelines and Indian National Ambient Air Quality Standards (NAAQS) for acceptable levels of daily exposure. Only a handful of studies have examined the short-term mortality effects of PM in India, with none from Delhi examining the contribution of PM2.5.

 

Objectives: 

We aimed to analyze the association between short-term PM2.5 exposures and daily nonaccidental mortality in Delhi, India.

 

Methods: 

Using generalized additive Poisson regression models, we examined the association between daily PM2.5 exposures and nonaccidental mortality between June 2010 and December 2016. Daily exposures to PM2.5 were estimated using an ensemble averaging technique developed by our research group, and mortality data were obtained from the Municipal Corporations of Delhi and the New Delhi Municipal Council.

 

Results: 

Median exposures to PM2.5 were 91.1 µg/m3 (interquartile range = 68.9, 126.2), with minimum and maximum exposures of 21.4 µg/m3 and 276.7 µg/m3, respectively. Total nonaccidental deaths recorded in Delhi during the study period were 700,512. Each 25 µg/m3 increment in exposure was associated with a 0.8% (95% confidence intervals [CI] = 0.3, 1.3%) increase in daily nonaccidental mortality in the study population and a 1.5% (95% CI = 0.8, 2.2%) increase in mortality among those with 60 years of age or over. The exposure-response relationship was nonlinear in nature, with relative risk rising rapidly before tapering off above 125 µg/m3. Meeting WHO guidelines for acceptable levels of exposure over the study period would have likely averted 17,526 (95% CI = 6,837, 25,589) premature deaths, with older and male populations disproportionately affected.

 

Discussion: 

This study provides robust evidence of the impact of short-term exposure to PM2.5 on nonaccidental mortality with important considerations for various stakeholders including policymakers and physicians. Most importantly, we find that reducing exposures significantly below current levels would substantially decrease the mortality burden associated with PM2.5.

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The limits of opportunism: the uneven emergence of climate institutions in India

Introduction

India’s centrality to global mitigation efforts makes it an important point of inquiry in studies of climate governance. However, we understand little of how climate change has been institutionalized in India’s decision-making processes. We capture the emergence and decline of climate institutions over three decades, showing how political conditions have shaped institutional form. The politics of opportunism has animated institutional development. It resolves the tension between India’s global leadership ambitions and a deeply entrenched, equity focused narrative frame that rejects incurring large mitigation costs. Climate institutions have therefore been layered upon existing bodies and processes to create room for the organic, bottom-up growth of policies that meet development objectives while promoting mitigation. While this structure limits polarization around climate action, it also inhibits strategic intent, particularly because strong cross-governmental institutions have been unable to take root.

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EIA 2020: Two Steps Back…

Introduction

The Ministry of Environment, Forest, and Climate Change (MoEFCC) published the draft Environment Impact Assessment (EIA) Notification 2020 in the Official Gazette on 11 April 2020. If brought into force, it will replace the existing EIA Notification 2006. It has met with widespread public opposition. According to some reports, the Environment Ministry has received 17 lakh representations in response, and politicians across party lines have strongly opposed the draft. In this essay, Shibani Ghosh provides a brief overview of the environment clearance process under the EIA notification, and discusses four principal reasons why the 2020 draft is misconceived and should be withdrawn. She then contextualizes these reasons within the broader regulatory landscape of the 2006 notification. As India awaits far-reaching regulatory reforms, Ghosh proposes four ways in which the existing regulatory framework can be strengthened to achieve significant environmental and social gains.

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Leveraging Existing Cohorts to Study Health Effects of Air Pollution on Cardiometabolic Disorders: India Global Environmental and Occupational Health Hub

Abstract

Air pollution is a growing public health concern in developing countries and poses a huge epidemiological burden. Despite the growing awareness of ill effects of air pollution, the evidence linking air pollution and health effects is sparse. This requires environmental exposure scientist and public health researchers to work more cohesively to generate evidence on health impacts of air pollution in developing countries for policy advocacy. In the Global Environmental and Occupational Health (GEOHealth) Program, we aim to build exposure assessment model to estimate ambient air pollution exposure at a very fine resolution which can be linked with health outcomes leveraging well-phenotyped cohorts which have information on geolocation of households of study participants. We aim to address how air pollution interacts with meteorological and weather parameters and other aspects of the urban environment, occupational classification, and socioeconomic status, to affect cardiometabolic risk factors and disease outcomes. This will help us generate evidence for cardiovascular health impacts of ambient air pollution in India needed for necessary policy advocacy. The other exploratory aims are to explore mediatory role of the epigenetic mechanisms (DNA methylation) and vitamin D exposure in determining the association between air pollution exposure and cardiovascular health outcomes. Other components of the GEOHealth program include building capacity and strengthening the skills of public health researchers in India through variety of training programs and international collaborations. This will help generate research capacity to address environmental and occupational health research questions in India. The expertise that we bring together in GEOHealth hub are public health, clinical epidemiology, environmental exposure science, statistical modeling, and policy advocacy.

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Rethinking India’s Energy Policy

Introduction

An energy supply approach is inadequate to India’s energy requirements at a time when multiple objectives need to be addressed. The state of play in energy supply and demand is examined, and the recovery of an older tradition of attention to energy demand patterns in addition to energy supply is argued for. The gains from an explicit attention to the fact that India has to address multiple and simultaneous objectives in shaping energy policymaking are laid out, and emerging methodologies to serve this goal are discussed. Shifts in governance patterns are a necessary part of transitioning to a broader, and more development-focused approach to energy policy.

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Exposure to Particulate Matter Is Associated With Elevated Blood Pressure and Incident Hypertension in Urban India

Abstract

Ambient air pollution, specifically particulate matter of diameter <2.5 μm, is reportedly associated with cardiovascular disease risk. However, evidence linking particulate matter of diameter <2.5 μm and blood pressure (BP) is largely from cross-sectional studies and from settings with lower concentrations of particulate matter of diameter <2.5 μm, with exposures not accounting for myriad time-varying and other factors such as built environment. This study aimed to study the association between long- and short-term ambient particulate matter of diameter <2.5 μm exposure from a hybrid spatiotemporal model at 1-km×1-km spatial resolution with longitudinally measured systolic and diastolic BP and incident hypertension in 5342 participants from urban Delhi, India, within an ongoing representative urban adult cohort study. Median annual and monthly exposure at baseline was 92.1 μg/m3 (interquartile range, 87.6–95.7) and 82.4 μg/m3 (interquartile range, 68.4–107.0), respectively. We observed higher average systolic BP (1.77 mm Hg [95% CI, 0.97–2.56] and 3.33 mm Hg [95% CI, 1.12–5.52]) per interquartile range differences in monthly and annual exposures, respectively, after adjusting for covariates. Additionally, interquartile range differences in long-term exposures of 1, 1.5, and 2 years increased the risk of incident hypertension by 1.53× (95% CI, 1.19–1.96), 1.59× (95% CI, 1.31–1.92), and 1.16× (95% CI, 0.95–1.43), respectively. Observed effects were larger in individuals with higher waist-hip ratios. Our data strongly support a temporal association between high levels of ambient air pollution, higher systolic BP, and incident hypertension. Given that high BP is an important risk factor of cardiovascular disease, reducing ambient air pollution is likely to have meaningful clinical and public health benefits.

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Climate laws help reduce emissions

Introduction

Over the last two decades, many countries have passed laws addressing climate change and related areas. Research now shows that these laws make a difference to emission outcomes, but the pathways of impact require further research.

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China and India in the Himalayan climate crisis

Summary

This article describes an unprecedented threat to large parts of India and China emanating from receding glaciers in the Himalaya. It posits that this threat will require these countries to redefine their security calculus by moving beyond military and economic fixations to incorporate an ecological dimension. It suggests four actions – two regional and two international – that could help them set the tone for cooperation in coming decades.

Some of these actions may seem unlikely against the backdrop of stark geopolitical competition today but this article points out that the building blocks for action have already been put in place: research networks for glacial science; regional electricity grids; international finance institutions jointly led by India and China; and joint negotiating positions that define international climate negotiations. The art of diplomacy will vest in transforming these incipient actions into transformative projects that not only define the bilateral relationship for the rest of the century, but make a dent in staving off the worst of a Himalayan disaster.

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Emissions: World has four times the work or one-third of the time

Summary

A decade of insufficient political action on climate change means that nations must now do four times the work — or do the same in one-third of the time — to comply with the climate pact they made in Paris. The authors’ conclusions are based on a synthesis of all ten editions of the Emissions Gap Report produced by the United Nations Environment Programme (UNEP). Each year for the past ten years, this report has examined the difference (the ‘gap’) between what countries have pledged to do individually to reduce greenhouse-gas emissions, and what they need to do collectively to meet agreed temperature goals. The co-authors find that the required emissions cuts from 2020 to 2030 are now more than 7% per year on average for the 1.5 °C temperature limit set in Paris and 3% for 2°C. Had serious climate action begun in 2010, the cuts required to meet the emissions levels for 2 °C would have been 2% per year, on average. The time window for halving global emissions has also narrowed: today it is 10 years for 1.5 °C and 25 years for 2°C; it would have been 30 years in 2010. Some countries, regions, cities and businesses have promised or implemented urgently needed climate action, however. For example, 76 countries or regions and 14 subnational regions or states have set or even implemented net-zero emissions goals. Closing the gap will require scaling up these few success stories and mirroring them with progress in every sector.

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