The pressing issue of earthy and musty odor compounds in natural waters, which can affect the organoleptic properties of drinking water, makes it a public health concern. A simple and sensitive method for simultaneous analysis of five odorants in environmental water was developed by headspace solid-phase microextraction (HS-SPME) coupled to chromatography-mass spectrometry (GC-MS), including geosmin (GSM) and 2-methylisoborneol (2-MIB), as well as dimethyl trisulfide (DMTS), β-cyclocitral, and β-ionone. Based on the simple modification of original magnetic stirrer purchased from CORNING (USA), the five target compounds can be separated within 23？min, and the calibration curves show good linearity with a correlation coefficient above 0.999 (levels？=？5). The limits of detection (LOD) are all below 1.3？ng？L？1, and the relative standard deviation (%RSD) is between 4.4% and 9.9% ( ) and recoveries of the analytes from water samples are between 86.2% and 112.3%. In addition, the storage time experiment indicated that the concentrations did not change significantly for GSM and 2-MIB if they were stored in canonical environment. In conclusion, the method in this study could be applied for monitoring these five odorants in natural waters. 1. Introduction Earthy and musty odors in drinking water are often associated with the metabolites which are produced in the degradation of cyanobacteria, actinomyces, fungi, and blue-green algae [1–3], including geosmin (GSM) and 2-methylisoborneol (2-MIB), commonly found in lakes and reservoirs [4, 5]. Moreover, attention now is drawn to the compounds dimethyl trisulfide (DMTS), β-cyclocitral, and β-ionone, which are also associated with algal blooms caused by eutrophication progress [6–9], and they often simultaneously break out in environmental waters [4, 10]. Beta-ionone, for instance, potentially derived from carotenoids, is the significant component of flavor and aroma in some fruits and vegetables [11, 12]. In studies conducted according to the SIDS initial assessment report [13], β-ionone has only low acute toxicity after oral ingestion by animal experiments and none of volunteers showed a positive reaction. More specifically, the two main exposures, occupational exposure may occur during manufacture and industrial using, which is the skin contact and inhalation and is limited by enclosed systems and personal protective measures, as well as consumer exposure in food and some house wares which is also low since small amounts around 5？ppm (parts per million) in food and at usual concentrations of up to 0.3% in cosmetics.
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