[en] Over 1100 pairs of coarse and fine filters were collected using Gent samplers and polycarbonate filters from 4 sites in Islamabad and Rawalpindi from the period 1998 to 2010. The Black carbon (BC) in these samples was determined by reflectance measurement while their elemental composition were determined using the techniques of instrumental neutron activation analysis (INAA), ion beam analysis (IBA) and X-ray fluorescence (XRF) spectrometry. Islamabad is a well planned and relatively small city as compared to Rawalpindi, Lahore or Karachi therefore its air quality is better than the air quality of other major Pakistani cities. It was found that the new air quality standards to be implemented in Pakistan with effect from January 2012 may not be attained even in Islamabad without the implementation of control and remedial measures. An overview of the elemental data obtained and calculation of enrichment factors (EF) and application of positive matrix factorization (PMF) showed that the particles in Islamabad originated from re-suspended soil, vehicular emissions and coal combustion. (Orig./A.B.)