Many studies have monitored atmospheric particulates and gaseous phases of PM2.5 in Asia over the past 10 years. This work also compared and discussed different sample collection, pretreatment and analytical methods in Asia countries in past decade. The results indicated that the main PM2.5 sources are traffic exhausts. PM2.5 concentrations are also ranked highest in the areas of traffic, followed by the urban sites, and lowest in rural sites in Asian countries. This work elucidates the sources, analytical tools, and the average concentrations for PM2.5 and related metallic elements during 1995-2005. The results indicated that the average highest concentrations order of metallic elements for PM2.5 were Fe > Mg > Zn, and the average concentrations of lowest metallic elements was Ph > Cu > Mn > Cr > Cd. The results also indicated that the concentration of metallic element Cu increased as the averaged concentrations of metallic element Zn and Mn increased during the past 10 years in Asian countries. (C) 2006 Elsevier B.V. All rights reserved.