A network of 10 sampling stations for the monitoring of elemental concentration of suspended particulate matter in the air of Tehran was established. Instrumental neutron activation analysis and atomic absorption spectrometry techniques were used for analysis of the filter samples collected during the period March 1994 - February 1995. Assessment of the results using the two techniques produced the following 21 elements with concentrations in units of mu g/m(3): Al 3.27 (+/-23%), As 0.013 (+/-32%), Br 0.43 (+/-30%), Ca 6.96 (+/-24%), Ce 0.014 (+/-16%), Co 0.008 (+/-18%), Cr 0.048 (+/-34%), Cs 0.006 (+/-22%), Fe 2.23 (+/-25%), K 2.15 (+/-24%), Mg 1.81 (+/-23%), Mn 0.078 (+/-25%), Na 1.68 (+/-21%), Ni 0.037 (+/-23%), Ph 1.02 (+/-47%), Sb 0.028 (+/-82%), Sc 0.001 (+/-17%), Se 0.002 (+/-31%), Ti 0.54 (+/-24%), V 0.019 (+/-31%), and Zn 0.327 (+/-12%). (C) 1999 Elsevier Science Ltd.