Grave health impacts

THE AIR WE BREATHE : Avoiding or ignoring the real human costs of living under increasingly polluted skies and hearths is simply not an option.

The term “particulate matter” (PM) may sound vaguely scientific and/ or removed from the seriously gr-ave health impacts that result from toxic air pollution, but the reality is that PM pollution is one of the leading health and morbidity risks facing the world today.

As the citizens of megalopolises such as New Delhi and Beijing know only too well, living under a PM-polluted sky is a daily price of life. But, the problem with this kind of air pollution is that it extracts an inequitable health and morbidity toll primarily in the densely populated megalopolises of Asia, where millions suffer the smothering burden of toxic skies and household hearths.

The development challenge of curbing outdoor and household pollution lies in the fact that this pollution emanates from many different types of sources ranging from small particles measuring 2.5 micrometres or less – PM 2.5 – which result from industrial, power plant, vehicular emissions, and also from wood stoves, open hearths and burning of agricultural residues, to more coarse particles between 2.5 and 10 micrometres which result from some agricultural processes, and road grinding dust. 

Sources of PM pollution therefore include traffic (especially diesel vehicles), industrial sectors (from brick making to oil and gas production), power plants, cooking and heating with solid fuels (coal, wood, crop waste), forest fires and open burning of municipal waste.

Reducing PM pollution therefore requires countries and cities to address a host of development concerns - transportation, industrial, agricultural, energy and infrastructure processes and services- all of which have serious socio-economic implications and all of which need to be addressed in a coordinated and organised manner.

While the first two weeks of 2016 have begun with Delhi residents experimenting with reducing the number of cars on the road with an odd-even licence plate formula to address outdoor air pollution, a neglected challenge remains- how to curb household air pollution.

The World Health Organisation (WHO) has highlighted their reversible damage caused to the lungs of young infants and children, and attributed 4.3  million premature deaths to household air pollution resulting from cooking with solid fuels (wood, crop wastes, charcoal, coal and dung), almost all in low and middle income countries in 2012.

While attention is now beginning to be paid to the outdoor air quality monitoring of PM levels, the disease and morbidity costs of the polluted hearth are shocking. In poorly ventilated dwellings, indoor smoke can be 100 times higher than acceptable levels for small soot particles (PM 2.5), with3.8 million premature deaths annually attributed to exposure to household air pollution and due to stroke, ischemic heart disease, chronic obstructive pulmonary disease and lung cancer.

Measuring 1/100th the thickness of a human hair, PM 2.5 can penetrate deep into human lungs and blood stream and is dangerous to human health. Clearly, addressing PM 2.5 pollution is critically important, but what is often not reflected in this equation is that one of the principal components of PM 2.5 – black carbon – which is emitted as a result of the incomplete combustion of fuel and biomass by diesel vehicles, open fires or solid fuels is known to be a short term climate pollutant.

In 2013, the United Nations Environment Programme Report pointed out that PM 2.5 is a component of black carbon; and that black carbon and ground level tropospheric ozone are two significant short lived climate pollutants. 

Increased cancer incidence

The International Agency for Research on Cancer (IARC) concluded in 2013 that particulate matter is carcinogenic to humans; with the PM 2.5 component of air pollution most closely associated with increased cancer incidence, especially cancer of the lung. An association also has been observed between outdoor air pollution and increase in cancer of the urinary tract/bladder.

What is less well known is that black carbon emissions are also directly linked to regional climate change impacts including regional rainfall and weather patterns such as the amplification of snow and ice cover patterns in the Himalayas and also the loss of annual regional production levels of rice, wheat and maize.

Reducing air pollution from vehicular and industrial emissions once considered the purview of more advanced industrialised countries is now unavoidably urgent for large, rapidly industrialising countries like China and India where the business of air quality monitoring and pollution abatement will boom but sadly also the disease burden and health costs of pollution.

For countries like India and Ban-gladesh, where the International Energy Agency estimates about 836 million (72 per cent of the population) and 143 million (88 per cent of the population) depend on traditional solid fuels/ biomass, and where vehicular emissions from unregulated diesel trucks, and the burning of garbage and crop wastes in close proximity to highly populated areas all combine to make a toxic air soup; curbing both indoor and outdoor air pollution is development imperative.

In this regard, the newly launched, India-led International Solar Alliance which 120 countries have already signed onto is an important step in promoting non-polluting energy sources. The following immediate measures which can simultaneously curb PM emissions and address short term climate change and thereby deliver multiple development benefits are worth implementing:

Cleaner Hearth Measures: Use of clean-burning biomass stoves; Use of clean burning cookstoves using modern and renewable energy sources.

Cleaner Sky Measures: Use of diesel particle filters for vehicles; Reduction of traffic congestion caused by unregulated cars and vehicles; Promotion of sustainable public transportation; Replacing traditional brick kilns with vertical shaft kiln; Replacing traditional coke oven with modern recovery oven, including end of pipe abatement measures; Ban on open field burning of agricultural/ crop wastes; and, Ban on burning of residential and industrial garbage/waste.

Avoiding or ignoring the real human costs of living under increasingly polluted skies and hearths is simply not an option because doing so will quite literally rob and destroy the future generation.

(Dr Cherian is author of Energy and Global Climate Change: Bridging the Sustainable Development Divide)