A simple monitoring method has been developed to determine the mean concentrations of pesticides in air over a period of one week. The pesticides investigated were buprofezin, edifenphos, ethofenprox, fenitrothion, fenobucarb, fenthion, flutolanil, fthalide, malathion, pencycuron, phentoate, pyridaphenthion, tetrachlorvinphos and tricyclazole. The pesticides were collected using quartz-fibre wool and activated carbon and eluted with acetone and toluene-ethanol (4:1, v/v). The eluate was reduced to a small volume and an acetone solution of the internal standards 1,4-diiodobenzene and 9-bromoanthracene was added for gas chromatography-mass spectrometry (GC-MS). Recoveries of the pesticides, indicating the overall performance of this method, ranged from 82.4 to 94.6%. The minimum detectable concentrations ranged from 0.1 ng/m(3) to 1 ng/m(3). This method has been successfully applied to the monitoring of pesticides in air over a rural area near paddy fields.