Determination of methanol in pesticide emulsifiable concentrate by headspace gas chromatography

A rapid headspace gas chromatography method for determination of methanol content in pesticide emulsifiable concentrate (EC) has been established.Capillary calumn DB-1701 was used as separation column and flame ionization detector(FID) as detection.Cyclohexane was used as internal standard (IS).The results showed that the regression of the peak area ratio of methanol to IS on the concentration of methanol fitted a linear relationship well (r=0.999 1) at the concentration levels ranging from 0.1% to 1.0% (V/V).The relative standard deviations (RSD) for 7 parallel determinations are less than 1.33%.Standard additions of methanol to blank formulation lead to recoveries of 95%-100%.The methodis simple and easily applicable,which provides a way for the determination of volatile adjuvant in liquid pesticide formulations.