SIMULTANEOUS DETERMINATION OF TRACE PESTICIDES IN URBAN AIR

Thirty-nine kinds of pesticides in the air were monitored in Kitakyush u City. Air samples were collected by a high-volume air sampler equipp ed with a quartz fiber filter and XAD-2 resin trap. After sampling abo ut 700 m3 of air, pesticides were extracted with dichloromethane from the quartz fiber filter and XAD-2 resin separately by ultrasonic metho d. The extracts were concentrated and fractionated by silica gel colum n chromatography. After adding internal standards, the sample solution s were analysed by gas chromatography/mass spectrometry with a selecte d ion monitor (GC/MS-SIM) using a fused silica capillary column for th e quantification of 39 kinds of pesticides. In order to evaluate the a ccuracy of this method, a recovery test was performed. Standard compou nds were spiked into the XAD-2 resin trap at a concentration level of 1 mug by sucking 700 m3 of sample air. The recovery efficiencies of al most all tested pesticides yielded more than 70% and their relative st andard deviations were less than 20%. This method was applied to monit or pesticides in air collected in summer and spring seasons in Kitakyu shu City. Of the 39 pesticides examined, 23 were detected in summer an d 21 detected in spring. The concentration of Isofenphos, 10 ng m-3, w as the highest in the summer sample and the concentration of propoxur, 11 ng m-3, in the spring sample.