title: Exposure assessment and associated lung deposition calculations for vehicular exhaust in four metropolitan cities of Pakistan.
abstract: Ambient aerosol concentrations along the roadside of metropolitan cities of Pakistan were measured using a Grimm 1.109 dust monitor. Considering the high ambient aerosol concentrations, regional lung deposition of aerosol particles in the human respiratory tract was calculated to assess extent of exposure. Lung deposition was computed in terms of mass concentration and the associated surface area for 12 male traffic wardens using the latest version of the stochastic lung deposition code Inhalation, Deposition, and Exhalation of Aerosols in the Lung. The results have revealed 4 to 10 times higher concentrations than recommended by WHO guidelines. The deposition results derived from the model disclose that extrathoracic deposition is in the range of 22 to 28 % with total lung deposition ranging from 40 to 44 % for the scanned particle window of 0.25-10 μm. Considering an average 8-h shift per day and an average breathing rate of 1.3 m(3) h(-1), it is approximated that in a worker, up to 1.6 mg of inhalable particle mass can deposit per day.
authors.affiliation: Division of Physics and Biophysics, Department of Materials Research and Physics, University of Salzburg, Hellbrunnerstrasse 34, 5020 Salzburg, Austria. majid.hussain@stud.sbg.ac.at
authors.forename: Hussain
authors.initials: H
authors.lastname: Majid
authors.forename: Khan
authors.initials: K
authors.lastname: Alam
authors.forename: Pierre
authors.initials: P
authors.lastname: Madl
authors.forename: Werner
authors.initials: W
authors.lastname: Hofmann
mesh_terms: D000393:Air Pollutants / Q000032:analysis; D000397:Air Pollution / Q000706:statistics & numerical data*; D002947:Cities / Q000706:statistics & numerical data; D006801:Humans; D019570:Inhalation Exposure / Q000032:analysis / Q000706:statistics & numerical data*; D008168:Lung; D008297:Male; D010154:Pakistan; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D000393:Air Pollutants; D001335:Vehicle Emissions