Source apportionment of inorganic ions in airborne urban particles from Coruna city (NW of Spain) using positive matrix factorization

Water-soluble atmospheric particulate matter was analyzed for pH, conductiv ity and inorganic ions: Mg2+, Ca2+, K+, Na+, NH4+, Cl-, NO3- and SO42- by i on-chromatography. In order to get a deeper insight on the atmospheric data and assess the 'optimal' number of pollution sources, principal component analysis and cluster analysis were applied. After that, the second objectiv e was to apply a recently developed chemometric technique (positive matrix factorization) to perform source apportionment and get ion balances. Four p ollution patterns were identified, namely, marine, industrial, urban and bu ilding-related source pollutants. Ion balances were also made in a straight forward manner. (C) 1999 Elsevier Science B.V. All rights reserved.