Last week, researchers at Yale and Columbia Universities published a report; the 2018 Environmental Performance Index (EPI) report, in collaboration with the World Economic Forum (WEF) ranking 180 countries. The ranking is based on Environmental Health and Ecosystem Vitality of each of those countries. The environmental health topic covers three issue categories namely Air quality, Water quality and Heavy metals and the ecosystem vitality topic covers seven issue categories namely Biodiversity and habitat, Forests, Fisheries, Climate and energy, Air pollution, Water resources and Agriculture; hence a total of ten issue categories. Each of these ten issue categories is, in turn, scored based on one to six performance indicators and there are altogether 24 such indicators.
After the report got published, Nepalese media published news stating that Nepal ranks 176th among 180 countries in terms of air pollution. Some ‘mainstream’ called media too published news stating the same. They further stated air pollution as a leading environmental threat to public health. The press release by Yale has clearly stated that air quality is the top environmental threat to public health, not air pollution as most of the news reports in Nepal wrote. They did not note the distinction between air quality and air pollution and wrongly transliterated air quality as air pollution. No doubt that Nepal is ranked at the bottom (180th country) in terms of air quality with a score of 3.94. But the rank of Nepal in terms of air pollution is 87 with a score of 49.58 and the overall EPI rank is 176 with a score of 31.44. (See country report/Nepal)
The performance indicators of air pollution in this study include Sulphur dioxide (SO2) emissions and Nitrogen oxides (NOX) emissions whereas performance indicators of air quality include (Particulate Matters of less than 2.5-micrometer diameter) PM2.5 exposure, PM2.5 exceedance and household solid fuels. The level of PM2.5 we have been hearing generally and exclaiming air pollution level in Kathmandu is the indicator of air quality, not air pollution in this study.
In a nutshell, it is not that the air pollution is the highest in Nepal but that the air quality is the worst.