• Ramin Nabizadeh Nodehi Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
  • Seyed Yaser Hashemi Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
  • Faramarz Azimi Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran
  • Shima Khorsand Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran
Keywords: Nanoparticles, diesel buses, BRT, size distribution


Introduction: Motor vehicles are the most important sources of gaseous and particulate matter emission in urban areas with the serious health effects which cause the respiratory and cardiovascular diseases and mortality. Motor vehicles emit a broad range of PM from 0.003 to 10 μm.Materials and methods: The exhaust emission of BRT and diesel buses was samples by portable environmental dust monitor, model EDM 107 during summer and winter 2016. ANOVA was applied at a significant level (Pvalue < 0.5) to compare the amount of emitted particles in each season.Results: The lowest concentration of emission was seen in BRT buses and the average number of particles in every liter of exhaust sample was 776330 ± 40428. The amount of emission from BRT buses in winter was 166217 ± 971870. There is a significant difference between total emissions of nanoparticles releasing by diesel and BRT buses in each season, but there isn’t any significant difference between the emissions of nanoparticles releasing by diesel buses in summer and winter.Conclusions: There was the high emission of particles emitted by diesel buses in both seasons. Since the impacts of particulate matters on health should be considered in Tehran, planning the best locations for bus terminals and also monitoring these places continuously are recommended.


Soylu S. Development of PN emission factors for the

real world urban driving conditions of a hybrid city bus.

Applied Energy. 2015; 138: 488-495.

Keogh DU, Ferreira L, Morawska L. Development of

a particle number and particle mass vehicle emissions

inventory for an urban fleet. Environmental Modelling

& Software, 2009. 24(11): 1323 - 1331.

Vouitsis I, Ntziachristos L, Samaras C, Samaras Z. Particulate

mass and number emission factors for road vehicles

based on literature data and relevant gap filling

methods. Atmospheric Environment. 2017;168:75-89.

Ardanese R, Ardanese M, Besch MC, Adams TR, Thiruvengadam

A, Shade BC, et al. PM Concentration and

Size Distributions from a Heavy-duty Diesel Engine

Programmed with Different Engine-out Calibrations to

Meet the 2010 Emission Limits. SAE Technical Paper;

Report No.: 0148-7191.

Vu TV, Delgado-Saborit JM, Harrison RM. Particle

number size distributions from seven major sources and

implications for source apportionment studies. Atmospheric

Environment. 2015;122:114-32.

Lähde T, Virtanen A, Happonen M, Söderström C, Kytö

M, Keskinen J. Heavy-duty, off-road diesel engine lowload

particle number emissions and particle control.

Journal of the Air & Waste Management Association.


Banerjee T, R Christian. A review on nanoparticle dispersion

from vehicular exhaust: Assessment of Indian

urban environment. Atmospheric Pollution Research,

Oberdörster G, Utell MJ. Ultrafine particles in the urban

air: to the respiratory tract--and beyond? Environmental

health perspectives. 2002;110(8):A440.

Mayer A, M Kasper , Czerwinski J. Nanoparticle

counts emissions of Trucks: EURO 3 with and without

DPF compared to EURO 4 and EURO 5. Energy and

Power, 2014. 4(1A): p. 1-10.

Jung S, Lim J, Kwon S, Jeon S, Kim J, Lee J, et al.

Characterization of particulate matter from diesel passenger

cars tested on chassis dynamometers. Journal of

Environmental Sciences. 2017;54:21-32.

Knibbs LD, Cole-Hunter T, Morawska L. A review of

commuter exposure to ultrafine particles and its health

effects. Atmospheric Environment, 2011. 45(16): p.


Holmén BA, Ayala A. Ultrafine PM emissions from

natural gas, oxidation-catalyst diesel, and particle-trap

diesel heavy-duty transit buses. Environmental science

& technology, 2002. 36(23): 5041-5050.

Thiruvengadam A, Besch MC, Yoon S, Collins J, Kappanna

H, Carder DK, et al. Characterization of particulate

matter emissions from a current technology natural

gas engine. Environmental science & technology.


Hallquist Å, Jerksjö M, Fallgren H, Westerlund J, Sjödin

Å. Particle and gaseous emissions from individual

diesel and CNG buses. Atmospheric Chemistry and

Physics. 2013;13(10):5337-50.

Alanen J, Saukko E, Lehtoranta K, Murtonen T, Timonen

H, Hillamo R, et al. The formation and physical

properties of the particle emissions from a natural gas

engine. Fuel. 2015;162:155-61.

Guo J, Ge Y, Hao L, Tan J, Li J, Feng X. On-road measurement

of regulated pollutants from diesel and CNG

buses with urea selective catalytic reduction systems.

Atmospheric environment. 2014;99:1-9.

Jayaratne E, He C, Ristovski Z, Morawska L, Johnson

G. A comparative investigation of ultrafine particle

number and mass emissions from a fleet of on-road diesel

and CNG buses. Environmental science & technology.


Aslam M, Masjuki H, Kalam M, Abdesselam H,

Mahlia T, Amalina M. An experimental investigation

of CNG as an alternative fuel for a retrofitted gasoline

vehicle. Fuel. 2006;85(5-6):717-24.

How to Cite
Original Research