KARACHI - The air pollution impacts on mortality and health are a significant public health issue worldwide. The population-based studies have documented health risks resulting from short term exposure to air pollutants.

The World Health Organization (WHO) reports that air pollution has become the world’s single biggest environmental health risk, linked to around seven million humans, nearly one in eight deaths in 2012.

Around 80 percent of the 3.7 million deaths from outdoor air pollution came due to stroke and heart disease, 11 percent from lung diseases, six percent from cancers. The Southeast Asia is now the most polluted region globally, with 2.6 million deaths related to the outdoor air pollution . These new estimates are based not on a significant increase in pollution, but on improved knowledge of the links between air pollutants and cardiopulmonary diseases.

These views were expressed by Dr Haider A Khwaja from Wadsworth Centre, Department of Environmental Health Sciences, School of Public Health, University at Albany, NY, USA while delivering one of the plenary lectures at fifth international conference on environmental horizon jointly organised by the Department of Chemistry and Office of Research Innovation and Commercialization (ORIC), University of Karachi and International Centre for Chemical and Biological Sciences (ICCBS), KU, on Sunday.

The three-day long event was scheduled at Professor Dr Salimuzzaman Siddiqui Auditorium, ICCBS, KU, from Friday till Sunday. The Professor Emeritus and former federal minister for science and technology, Atta-ur-Rahman, shared with audience that knowledge is not the single most important factor for socio-economic development and science and technology are great equalisers. Countries that have realised this and invested heavily in developing their human resources to the highest possible levels have leaped forward, leaving others far behind.

Meanwhile, the Director ICCBS, KU, Professor Dr M Iqbal Choudhary, mentioned that biodiversity is an outward manifestation of chemical diversity and plants contain a fascinating array of highly evolved, specific and effective gene products. Their diverse structural and stereo-chemical characteristics make them valuable templates for exploring novel molecular diversity.

Another speaker, Parisa A Ariya of Department of Chemistry and Department of Atmospheric and Oceanic Sciences, McGill University, Montreal, QC, Canada, shared that the International Panel for Climate Change (IPCC) and the WHO have identified airborne particles as a research priority of the utmost importance.

She mentioned that the IPCC points to the importance of the aerosol-cloud processes due to their impacts on the absorption and scattering of irradiation, altering the earth’s climate whereas the WHO predominantly considers aerosols as to be health hazards.

Sheryl H Ehrman from Davidson College of Engineering, San Jose State University, USA, informed the audience that over the past two decades, anthropogenic pollutants have been successfully reduced in the mid-Atlantic region of the United States, resulting in improved air quality.

However, she said that parts of the mid-Atlantic still are considered non-attainment regions and ozone remains the main criteria pollutant of concern. The ozone is a secondary air pollutant, formed by reactions between volatile organic compounds and nitrogen oxides. Ozone precursors are mainly emitted by power plants, motor vehicles, industrial operations and biogenic sources.

“In the past several years, a new influx of emissions associated with hydraulic fracturing based production of natural gas in the Marcellus shale play may be counteracting the benefits that have been gained. On the flip-side, low cost natural gas could replace coal as fuel for power plants, potentially reducing emissions.”

The Director, Wisconsin State laboratory of Hygience, Peterson-Rader-Hawnn Professor of Civil and Environmental Engineering, University of Wisconsin-Madison, Dr James J Schauer, mentioned that the association of atmospheric particulate matter (PM) with the adverse health effects has been well established and has led to the promulgation of PM standards and the implementation of control measures to reduce OM concentrations.

He elaborated that given the complex nature of the source of PM, there are different strategies that can be used in air pollution control programs targeted at reducing the impact of PM. From a public health perspective, the sources of air pollution that have the biggest impact on the burden of disease should be targets for control but ability to link specific sources to health impacts is not well established.

According to him, for this reason, there is a need to develop collaborative efforts between atmospheric science studies and epidemiological and toxicological studies to establish has human exposure to specific sources of air pollution impact then pathogenesis and burden of disease.