Abstract
A method for the determination of earthy and musty odors (geosmin 、2-Methylisoborneol、2-isobutyl-3-methoxy pyrazine 、2-isopropyl-3-methoxy pyrazine and 2,4,6-trichloroanisole) in water by headspace solid-phase microextraction(HSSPME) combined with gas chromatography-ion trap mass spectrometry(GC-ITMS) is described. Several parameters of the extraction and desorption procedure were studied and optimized (such as types of fibers, extraction temperature, extraction time, desorption temperature, desorption time, ionic strength and elutropic strength, pH of samples). The method shows good linearity over the concentration range 1-500 ng /L and gives detection limits of sub-part-pertrillion level for all compounds. Good precisions (5.9-9.8%) are obtained using IBMP as internal standard. Finally, The method was successfully applied to analyze earthy and musty odors in tap water and lake water.