title: Distribution of lead in relation to size of airborne particulate matter in Islamabad, Pakistan.
abstract: Airborne particulate matter (PM) collected from two sampling stations in Islamabad, Pakistan, was analyzed for lead content and size gradation. A high volume air sampler was used to trap particulates on glass fiber filters for 8-12 h on a daily basis. Lead was estimated using a nitric acid digestion based AAS method on 44 samples from station 1 and 61 samples from station 2. Particle size fractions were categorized as <2.5, 2.5-10, 10-100 and >100 microm. The correlation between lead concentration and particle size was investigated. The results from two stations indicated average airborne lead concentrations of 0.505 and 0.185 microg/m3. Enhanced levels of lead were measured at a maximum of 4.075 microg/m3 at station 1 and 4.000 microg/m3 at station 2. PM < 2.5 and PM > 100 were found to constitute the local atmosphere in comparable proportions. A comparison of the lead levels is made with the existing permissible levels of this element laid down by different international agencies.
authors.affiliation: Department of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan.
authors.forename: Munir H
authors.initials: MH
authors.lastname: Shah
authors.forename: N
authors.initials: N
authors.lastname: Shaheen
authors.forename: M
authors.initials: M
authors.lastname: Jaffar
authors.forename: M
authors.initials: M
authors.lastname: Saqib
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D002947:Cities; D004784:Environmental Monitoring; D007854:Lead / Q000032:analysis*; D010154:Pakistan; D010316:Particle Size
chemical_list: D000393:Air Pollutants; D007854:Lead