Estimating emissions from open burning of municipal solid waste in municipalities of Nepal Bhupendra Das a,b,⇑ , Prakash V. Bhave b , Alka Sapkota c , Rejina M. Byanju a a Central Department of Environmental Science, Tribhuvan University, Kirtipur, Nepal b International Centre for Integrated Mountain Development, Lalitpur, Nepal c Solid Waste Management and Technical Support Centre, Lalitpur, Nepal article info Article history: Received 9 March 2018 Revised 5 August 2018 Accepted 6 August 2018 Keywords: Municipal waste generation MSW open burning Air pollutants Emission inventory Health impact abstract Open burning of municipal solid waste (MSW) is a poorly-characterized and frequently-underestimated source of air pollution in developing countries. This paper estimates the quantity of MSW that was burned in five erstwhile municipalities of the Kathmandu valley, Nepal. A household survey, a transect walk survey, an experiment to measure the fraction of waste that is combustible, a survey on fraction of population burning waste outside their houses, and a survey of the fraction of MSW burned at dump sites were performed in this study, whereas burning/oxidation efficiency, municipal populations, MSW generation rates, and emission factors were derived from the literature. The total mass of MSW burned during 2016 is estimated to be 7400 tons (i.e., 20 tons/day), which was of 3% of the total MSW generated in the valley municipalities that year. This exceeds Government estimates by a factor of three. Multiplying the burned MSW mass by emission factors, the air pollutant emissions are estimated as PM 2.5 55 tons (OC 42 tons and EC 1.4 tons), PM 10 60 tons, BC 25 tons, CO 2 11,900 tons, CH 4 30 tons, SO 2 5.0 tons, NO x 19.2 tons, CO 630 tons, NMVOC 112 tons, and NH 3 5.7 tons per year. Open burning of MSW can trigger health impacts such as acute and chronic respiratory disease, heart diseases, and allergic hypersensitivity, in addition to impacts on local climate. Improved waste-segregation practices at the source and waste-collection systems throughout the valley are needed to mitigate this pollution source and its effects. Ó 2018 Elsevier Ltd. All rights reserved. 1. Introduction Solid waste management (SWM) has become a major concern, especially in urban areas of developing countries. Many municipal- ities are experiencing extreme environmental degradation as well as public health risks due to ill-timed waste management and unsanitary disposal practices (Alam et al., 2008; Nagpure et al., 2015). Recently, the open burning of solid waste was implicated as a major cause for soiling the Taj Mahal and impairing the health of Agra residents (Lal et al., 2016). In Nepal, population growth, rapid expansion of sprawling urban municipalities, increasing amounts of industrial and commercial activity, and rising con- sumption of packaged goods has resulted in severe air and water quality issues, poor sanitation, and the spread of diseases (Alam et al., 2008; Dangi, 2009; Pokhrel and Vivaraghavan, 2005). At an elevation of 1400 m, the bowl-shaped Kathmandu valley lies at the foothills of the Himalayas and is surrounded by moun- tains and forests. The total urban area of Kathmandu valley is 96.68 km 2 (KVDA, 2017) and this area has the highest population density in Nepal. The valley contains five densely-inhabited urban centres which were previously designated as municipalities: Kath- mandu Metropolitan City (KMC), Lalitpur Sub-Metropolitan City (LSMC), Bhaktapur, Kirtipur and Madhyapur Thimi. Around the time of study, the Government of Nepal designated 16 municipal- ities (dividing many of the earlier five into smaller areas) in the valley partly in response to the booming urban population (KVDA, 2017). Fig. 1 contains a map of the five original municipalities referred to throughout this study and their location within Nepal. KMC is home to the nation’s capital and is the most populated municipal- ity in Nepal with an area of 49.45 km 2 (CBS, 2013) subdivided into 35 wards (KMC, 2014). LSMC was the country’s third most popu- lous municipality and is located in the south-central part of the valley, covering an area of 24.94 km 2 that was subdivided into 30 wards (LSMC, 2016). Bhaktapur is an ancient city in the eastern https://doi.org/10.1016/j.wasman.2018.08.013 0956-053X/Ó 2018 Elsevier Ltd. All rights reserved. ⇑ Corresponding author. E-mail addresses: bhupenids@gmail.com (B. Das), rmaskey@cdes.edu.np (R.M. Byanju). Waste Management 79 (2018) 481–490 Contents lists available at ScienceDirect Waste Management journal homepage: www.elsevier.com/locate/wasman