Air pollution and human health in Kathmandu valley

[PHP Nepal Vol 2 Issue 5 May 2012] | Epidemiological literature has established that high concentrations of lower atmospheric pollution such as ozone, lead, and particulate matter contribute to human morbidity and mortality. Humans can inhale particulate matter with an aerodynamic size less than 10 microgram (called PM10) into the thoracic, which then moves to the lower regions of the respiratory tract carrying the potential to induce harm. The high concentration of air pollution may cause runny nose, sinusitis, headache (migraine), flu, allergy symptoms, cough, asthma, and bronchitis among others. Prolonged exposure may lead to irritation, headache, fatigue, asthma, high blood pressure, heart diseases, and even cancer.

The air pollution in Kathmandu Valley is ever increasing. Rapid unmanaged urbanization in the capital city has resulted in a significant deterioration of air quality. The vehicular emissions, poorly managed vehicle, re-suspension of street dust and litter, black smoke plumes from brick kilns, and refuse burning are other sources contributing to increased air pollution in the valley. Vehicular emissions are responsible for 38% of the total Particulate Matter PM10 (particles measuring 10μm or less) emitted in the Kathmandu compared to the agricultural sector (18%) and the brick kilns (11%) (International Centre for Integrated Mountain Development, 2006). The increase in vehicular emissions is mainly due to increase in the number of automobiles, poor transport management system, and poor vehicle maintenance. 

The information on PM10 from Kathmandu valley reveals two important features. First, the consequent post monsoon periods (winter and summer) have high PM10 level as compared to the monsoon seasons. Second, the cities such as Putalisadak and Thamel are more polluted compared to cities like Bhaktapur and Kirtipur. In addition, the outer valley was less polluted than the inner valley. According to the Ministry of Environment report, the PM10 (g/m3) less than 60 is good, 60-119 is moderate, 120-349 is unhealthy, 350-425 is very unhealthy, and more than 425 is hazardous for human health. 

Recently a study was carried out by Central Department of Economics, Tribhuvan University, South Asian Network for Development and Environmental Economics (SANDEE), to provide an estimate of the health benefits to the residents of Kathmandu from a reduction in the current air pollution level of 254.75 g/m3 to a safe minimum level of 120 g/m3. It also analyzed the monetary costs of the treatment of air pollution related disease. The study was carried out over 12 weeks in four different seasons, among 120 households comprising 641 individuals from three different cities of Kathmandu (Thamel, Putalisadak and Patan). According to the study, the annual health and human welfare gain to a representative individuals of these cities from a reduction in air pollution from the current level to a safe minimum level is USD $1.85 as the health cost saved per annum.  The extrapolation of benefit estimates of a representative individual to the total population of two cities, Kathmandu and Lalitpur, provides an estimate of monetary benefits of USD $3.56 million per year. A calculation of the health benefits that would accrue to the residents of the two cities Kathmandu and Lalitpur under consideration yields a discounted benefit that is as high as NRs 4955 million (or USD $68.81 million) over the next 20 years. 

Given these figures that an individuals and households are spending on the treatment of air pollution related diseases, a Call for Action for air pollution control in Thamel, Putalisadak and Patan is needed. The government will need to focus on strong enforcement of existing policies that are aimed at controlling air pollution. In addition, it is essential for the government to address the needs for proper urbanization and to develop a clean energy master plan. In addition,, at the individual level, residents will need to do periodic vehicle maintenance to reduce auto pollution from poorly maintained vehicles, use mass transportation, consider clean energy star appliances when buying new appliances, decrease their heating with coal, carbon and oil, and other actions  to minimize the pollution level in the Valley.

Naveen Adhikari is Assistant Professor of Central Department of Economics at Tribhuvan Univeristy.

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