Simultaneous determination of trace pesticides in urban air

Thirty-nine kinds of pesticides in the air were monitored in Kitakyushu City. Air samples were collected by a high-volume air sampler equipped with a quartz fiber filter and XAD-2 resin trap. After sampling about 700 m' of air, pesticides were extracted with dichloromethane from the quartz fiber filter and XAD-2 resin separately by ultrasonic method. The extracts were concentrated and fractionated by silica gel column chromatography. After adding internal standards, the sample solutions were analysed by gas chromatography/mass spectrometry with a selected ion monitor (GC/MS-SIM) using a fused silica capillary column for the quantification of 39 kinds of pesticides. In order to evaluate the accuracy of this method, a recovery test was performed. Standard compounds were spiked into the XAD-2 resin trap at a concentration level of l μg by sucking 700 m 3 of sample air. The recovery efficiencies of almost all tested pesticides yielded more than 70% and their relative standard deviations were less than 20%. This method was applied to monitor pesticides in air collected in summer and spring seasons in Kitakyushu City. Of the 39 pesticides examined, 23 were detected in summer and 21 detected in spring. The concentration of Isofenphos, 10 ng m ·, was the highest in the summer sample and the concentration of propoxur, 11 ng m −3, in the spring sample.