The paper identifies the sources of fine and coarse inhalable particles at a site in metropolitan Boston and investigates their respective relationships to meteorological conditions. In the work, Principal Component Analysis (PCA) is applied to: (1) particle mass elemental data; (2) coarse particle mass elemental data, and (3) meteorological measurements (primarily collected at nearby Logan International Airport). In addition to local surface observations, air mass trajectory information concerning each sampling day is included in the meteorological data set, allowing the consideration of air mass transport as one factor in particle impacts. As part of these PCA analyses, four different objective component selection criteria are examined and compared. The screen test of eigenvalues is found to result in the most interpretable components for the specific air pollution and meteorological data sets considered in the work.