Determination of earthy-musty odors in tap water by gas chromatography‒mass spectrometry with silica solid-phase extraction
Liangliang Tian,
Xin Qu,
Dongmei Huang,
Yongfu Shi,
Cong Kong,
Yuan Wang
Affiliations
Liangliang Tian
East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, China; Key Laboratory of Oceanic and Polar Fisheries, Ministry of Agriculture and Rural Affairs, China
Xin Qu
Qingdao Municipal Center for Disease Control and Prevention, Qingdao, Shandong Province, 266033, China
Dongmei Huang
East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, China; Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China
Yongfu Shi
East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, China; Key Laboratory of Oceanic and Polar Fisheries, Ministry of Agriculture and Rural Affairs, China
Cong Kong
East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, China; Key Laboratory of East China Sea Fishery Resources Exploitation, Ministry of Agriculture and Rural Affairs, China
Yuan Wang
East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, China; Key Laboratory of Oceanic and Polar Fisheries, Ministry of Agriculture and Rural Affairs, China; Corresponding author. East China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shanghai, 200090, China.
This research aimed to develop an effective method for detecting semivolatile earthy-musty odors without using the conventional sample processing equipment used for volatile compounds. The concurrent isolation of 2-methylisoborneol (2-MIB), trans-1,10-dimethyl-trans-9-decalol (geosmin, GSM), 2-isopropyl-3-methoxy pyrazine (IPMP), and 2-isobutyl-3-methoxy pyrazine (IBMP) in tap water was successfully achieved by employing a combination of n-hexane liquid‒liquid extraction (LLE) and silica solid-phase extraction (SPE) techniques. Gas chromatography–mass spectrometry (GC-MS) was utilized for the identification of these targets, with the inclusion of borneol (BN) as an internal reference. This robust method was optimized and validated. It was found that the method showed good linearity in the range of 0.5–100 ng/mL and produced good recoveries (84.6 %–103 %) with satisfactory relative standard deviations (1.50 %–10.1 %). The determined limits of detection (LODs) for the group of four substances were found to vary from 0.3 to 0.9 ng/L, whereas the limits of quantitation (LOQs) exhibited variations between 1 and 3 ng/L. The subsequent implementation of this methodology to evaluate the four previously described off-flavor chemicals in tap water resulted in satisfactory results.
