Abstract: To determine residues of chlorpyrifos, pyridaben, fenpropathrin,and cyhalothrin in the atmosphere simultaneously, a gas chromatography(GC) method was developed. Air samples were collected using a high-volume PUF sampler and extracted with the technique of Soxhlet extraction using hexane. Concentrations of target pesticides in the samples were determined by gas chromatography-electron capture detection, and quantified with the external standard method. The linear range of the four pesticides was 50-1000ng •mL^-1(r >0.999). The mean recovery rates of the four pesticides in the air samples varied in the range of 80.94%-112.43% and relative standard(RSD) of the determination was in the range of 0.97%-8.58%.The limit of detection is 0.016 7, 0.028 7, 0.045 6, and 0.016 2 mg•m^-3, respectively, for of chlorpyrifos, pyridaben, fenpropathrin and cyhalothrin. This method is applicable to determination of concentrations of pesticides in the surrounding atmosphere of a pesticide factory.

Key words: PUF, gas chromatography, chlorpyrifos, pyridaben, fenpropathrin, cyhalothrin