Emissions of DEHP-free PVC flooring.

Degrading 2-ethylhexyl-containing PVC floorings (eg DEHP-PVC floorings) and adhesives emit 2-ethylhexanol (2-EH) in the indoor air. The danger of flooring degradation comes from exposing occupants to harmful phthalates plasticisers (eg DEHP), but not from 2-EH as such. Since the EU banned the use of phthalates in sensitive applications, the market is shifting to use DEHP-free and alternative types of plasticisers in PVC products. However, data on emissions from DEHP-free PVC floorings are scarce. This study aimed at assessing the surface and bulk emissions of two DEHP-free PVC floorings over three years. The floorings were glued on the screed layer of concrete casts at 75%, 85%, and 95% RH. The volatile organic compounds (VOCs) were actively sampled using FLEC (surface emissions) and micro-chamber/thermal extractor (µ-CTE, bulk emissions) onto Tenax TA adsorbents and analyzed with TD-GC-MS. 2-EH, C9-alcohols, and total volatile organic compound (TVOC) emissions are reported. Emissions at 75% and 85% RH were similar. As expected, the highest emissions occurred at 95% RH. 2-EH emissions originated from the adhesive. Because the two DEHP-free floorings tested emitted C9-alcohols at all tested RH, it makes the detection of flooring degradation harder, particularly if the adhesive used does not emit 2-EH.

Identification and quantification of glue-like off-odors in elastic therapeutic tapes.

Elastic therapeutic tapes are an important tool in the field of physical therapy and medicine. These tapes contain types of adhesive. However, sensory evaluations revealed the release of pronounced and irritating odors of the tapes. Negative odors were, amongst others, reported in elastic therapeutic tapes containing acrylic adhesives. In this study, the odor of four different tape samples was evaluated applying a descriptive analysis approach carried out by a trained sensory panel. Afterwards, the volatile compounds were recovered from the samples by solvent extraction and isolated by solvent-assisted flavor evaporation (SAFE). The obtained distillates were subsequently analyzed by gas chromatography-olfactometry (GC-O) and two-dimensional GC-O coupled with mass spectrometry (2D-GC-MS/O). To determine the most potent odorants in the distillates, odor extract dilution analyses (OEDA) were carried out. Thirty-one odorants were successfully identified using this approach, which were all described for the first time as odorants in tapes. Amongst the set of volatiles, unsaturated and saturated aldehydes were present, eliciting fatty, soapy, and citrus-like odor impressions, as well as a range of glue-like, moldy, and fruity smelling odor-active volatiles, such as 2-ethyl-1-hexanol, butyl benzoate, and 3-phenyltoluene. Based on their relative intensities, the concentrations of the glue-like smelling substances were determined: 2-ethyl-1-hexanol, present in all samples, was determined with concentrations ranging from 10 to 200 mg/kg in the investigated tapes.

An endophytic Fusarium sp. isolated from Monarda citriodora produces the industrially important plant-like volatile organic compound hexanal.

An endophytic fungus, MC_25L, has been isolated from the leaves of MonardacitriodoraCerv. ex Lag., a medicinal and aromatic herb from the northwestern Himalayas. It produces a fruity fragrance while growing on potato dextrose agar, suggesting that it is producing volatile organic compounds (VOCs). The endophyte inhibited the growth of plant pathogens such asSclerotiniasp. and Aspergillusflavus by virtue of VOCs. Identification of MC_25L based on morphological and microscopic features, as well as ITS-based rDNA sequence analysis, revealed that it is a Fusariumsp. GC-MS analysis revealed that this endophyte produces a unique array of VOCs, in particular hexanal, p-fluoroanisole, pentafluoropropionic acid 2-ethylhexyl, (5E)-5-ethyl-2-methyl-5-hepten-3-one, 2-butyl-2-hexanol, (7E)-2-methyl-7-hexadecene and acoradiene. Three major compounds were hexanal, (5E)-5-ethyl-2-methyl-5-hepten-3-one and acoradiene, and they account for around 84.57 % of the total VOCs. Moreover, of interest was the presence of hexanal, which has applications in the food and cosmetic industries, as well as in mycofumigation. This is the first report of a fungal endophyte producing the industrially important plant-like VOC hexanal. Hexanal is also active biologically. Thus this study indicates that Fusariumsp. (MC_25L) is a potential candidate for the up-scaling of hexanal.

Direct immersion solid-phase microextraction with gas chromatography and mass spectrometry for the determination of specific biomarkers of human sweat in melted snow.

To provide a reliable tool for investigating diffusion processes of the specific components of the human odor 3-hydroxy-3-methylhexanoic acid and 3-methyl-3-sulfanylhexan-1-ol through the snowpack, we developed and optimized an analytical method based on direct immersion solid-phase microextraction followed by gas chromatography with mass spectrometry. Direct immersion solid-phase microextraction was performed using polyacrylate fibers placed in aqueous solutions containing 3-hydroxy-3-methylhexanoic acid and 3-methyl-3-sulfanylhexan-1-ol. After optimization, absorption times of 120 min provided a good balance to shorten the analysis time and to obtain suitable amounts of extractable analytes. The extraction efficiency was improved by increasing the ionic strength of the solution. Although the absolute extraction efficiency ranged between 10 and 12% for 3-hydroxy-3-methylhexanoic acid and 2-3% for 3-methyl-3-sulfanylhexan-1-ol, this method was suitable for analyzing 3-hydroxy-3-methylhexanoic acid and 3-methyl-3-sulfanylhexan-1-ol concentrations of at least 0.04 and 0.20 ng/mL, respectively. The precision of the direct immersion solid-phase microextraction method ranged between 8 and 16%. The variability within a batch of six fibers was 10-18%. The accuracy of the method provided values of 88-95 and 86-101% for 3-hydroxy-3-methylhexanoic acid and 3-methyl-3-sulfanylhexan-1-ol, respectively. The limit of detection (and quantification) was 0.01 ng/mL (0.04 ng/mL) for 3-hydroxy-3-methylhexanoic acid and 0.06 ng/mL (0.20 ng/mL) for 3-methyl-3-sulfanylhexan-1-ol. The signal versus concentration was linear for both compounds (r(2) = 0.973-0.979). The stability of these two compounds showed that 3-hydroxy-3-methylhexanoic acid was more stable in water than 3-methyl-3-sulfanylhexan-1-ol. We applied the method to environmental samples in correspondence with an olfactory target buried previously.

Identification of signature volatiles to discriminate Candida albicans, glabrata, krusei and tropicalis using gas chromatography and mass spectrometry.

Oral candidiasis is the most frequent fungal infection of the oral cavity. Clinical diagnoses require mycological confirmation, which is time-consuming in case of culture testing. The aim of the study was to identify signature volatiles to develop a chairside breath test to diagnose oral candidiasis. Headspaces above Candida albicans, glabrata, tropicalis, krusei cultures, and growth media as control were analysed after eight and 24 h using offline gas chromatography and mass spectrometry. The identification of signature volatiles was assisted using various microbial databases. Retrieved volatile patterns enabled Candida species discrimination in vitro. For C. albicans 3-methyl-2-butanone and styrene and for C. krusei a combination of p-xylene, 2-octanone, 2-heptanone and n-butyl acetate were found to be specific. 1-hexanol was found in C. tropicalis, but is emitted by a variety of other microorganisms. C. glabrata was characterised through the absence of these volatiles. The development of a breath test is a promising approach in confirming suspicions of oral candidiasis. To confirm the retrieved results in vivo, breath tests in affected and healthy subjects have to be performed.

Microbiological spoilage and volatiles production of gutted European sea bass stored under air and commercial modified atmosphere package at 2 °C.

Microbiological, sensory, TVB-N and TMA-N changes and Volatile Organic Compounds (VOCs) detection using the SPME/GC-MS technique, were performed to evaluate potential chemical spoilage indices (CSI) of gutted sea bass (Dicentrarchus labrax) stored at 2 °C under air and in modified atmosphere packaging (MAP CO2: 60%, O2: 10%, N2: 30%). Shelf-life, determined by sensory evaluation, of gutted sea bass stored at 2 °C under air and MAP was 9 and 13 d respectively. Pseudomonas and H2S producing bacteria were among the dominant spoilage microorganisms under both storage conditions, while Lactic Acid Bacteria (LAB) and Brochothrix thermosphacta were co-dominant with Pseudomonas and H2S producing bacteria under MAP. The traditional CSIs such as TVB-N and TMA-N were increased substantially only at the late stages of storage or after rejection of the products, making them unsuitable for freshness/spoilage monitoring throughout storage. A substantial number of VOCs attributed to microbiological action or chemical activity, were detected including alcohols, aldehydes, ketones, organic acids and esters. The level of microbial origin VOCs such as ethanol, 2-ethyl-1-hexanol, 3-methyl-1-butanol, 2-methyl-1-butanol, 3-methylbutanal, 2-methylbutanal and some ethyl esters increased during storage, suggesting their potential as CSIs.

Derivatization of pinacolyl alcohol with phenyldimethylchlorosilane for enhanced detection by gas chromatography-mass spectrometry.

A derivatization procedure for the qualitative gas chromatography-mass spectrometry (GC-MS) analysis of pinacolyl alcohol (PA) that employs phenyldimethylchlorosilane (PhDMClS) and the promoter N-methylimidazole is described. While PA, underivatized, can be detected using conventional gas chromatographic methods, its polarity and low boiling point make its detection in complex matrices challenging. The silylation procedure described herein generates a PA-derivative exhibiting an increased on-column retention time, thus shifting its GC-MS signal away from commonly encountered, volatile, interfering analytes. Derivatized PA could be distinguished from other PhDMClS-derivatized isomeric alcohols by its unique retention time and mass spectrum. The derivatization was demonstrated to perform well in the GC-MS analysis and identification of PA in samples from Proficiency Tests administered by the Organisation for the Prohibition of Chemical Weapons (OPCW).

"Fooling fido"--chemical and behavioral studies of pseudo-explosive canine training aids.

Genuine explosive materials are traditionally employed in the training and testing of explosive-detecting canines so that they will respond reliably to these substances. However, challenges arising from the acquisition, storage, handling, and transportation of explosives have given rise to the development of "pseudo-explosive" training aids. These products attempt to emulate the odor of real explosives while remaining inert. Therefore, a canine trained on a pseudo-explosive should respond to its real-life analog. Similarly, a canine trained on an actual explosive should respond to the pseudo-explosive as if it was real. This research tested those assumptions with a focus on three explosives: single-base smokeless powder, 2,4,6-trinitrotoluene (TNT), and a RDX-based plastic explosive (Composition C-4). Using gas chromatography-mass spectrometry with solid phase microextraction as a pre-concentration technique, we determined that the volatile compounds given off by pseudo-explosive products consisted of various solvents, known additives from explosive formulations, and common impurities present in authentic explosives. For example, simulated smokeless powders emitted terpenes, 2,4-dinitrotoluene, diphenylamine, and ethyl centralite. Simulated TNT products emitted 2,4- and 2,6-dinitrotoluene. Simulated C-4 products emitted cyclohexanone, 2-ethyl-1-hexanol, and dimethyldinitrobutane. We also conducted tests to determine whether canines trained on pseudo-explosives are capable of alerting to genuine explosives and vice versa. The results show that canines trained on pseudo-explosives performed poorly at detecting all but the pseudo-explosives they are trained on. Similarly, canines trained on actual explosives performed poorly at detecting all but the actual explosives on which they were trained.

Drosophila melanogaster as a model to characterize fungal volatile organic compounds.

Fungi are implicated in poor indoor air quality and may pose a potential risk factor for building/mold related illnesses. Fungi emit numerous volatile organic compounds (VOCs) as alcohols, esters, ethers, ketones, aldehydes, terpenoids, thiols, and their derivatives. The toxicity profile of these VOCs has never been explored in a model organism, which could enable the performance of high throughput toxicological assays and lead to a better understanding of the mechanism of toxicity. We have established a reductionist Drosophila melanogaster model to evaluate the toxicity of fungal VOCs. In this report, we assessed the toxicity of fungal VOCs emitted from living cultures of species in the genera, Trichoderma, Aspergillus, and Penicillium and observed a detrimental effect on larval survival. We then used chemical standards of selected fungal VOCs to assess their toxicity on larval and adult Drosophila. We compared the survival of adult flies exposed to these fungal VOCs with known industrial toxic chemicals (formaldehyde [37%], xylene, benzene, and toluene). Among the tested fungal VOC standards, the compounds with eight carbons (C8) caused greater truncation of fly lifespan than tested non-C8 fungal VOCs and industrial toxins. Our data validate the use of Drosophila melanogaster as a model with the potential to elucidate the mechanistic attributes of different toxic VOCs emitted by fungi and also to explore the potential link between reported human illnesses/symptoms and exposure to water damaged and mold contaminated buildings.

Determination of volatile organic compounds (VOCs) from wrapping films and wrapped PDO Italian cheeses by using HS-SPME and GC/MS.

Nowadays food wrapping assures attractive presentation and simplifies self-service shopping. Polyvinylchloride (PVC)- and polyethylene (PE)-based cling-films are widely used worldwide for wrapping cheeses. For this purpose, films used in retail possess suitable technical properties such as clinginess and unrolling capacity, that are achieved by using specific plasticizers during their manufacturing process. In the present study, the main VOCs of three cling-films (either PVC-based or PE-based) for retail use were characterized by means of Solid-Phase Micro-Extraction and GC/MS. In addition, the effects of cling film type and contact time on the migration of VOCs from the films to four different PDO Italian cheeses during cold storage under light or dark were also investigated. Among the VOCs isolated from cling-films, PVC released 2-ethylhexanol and triacetin. These compounds can likely be considered as a "non-intentionally added substance". These same compounds were also detected in cheeses wrapped in PVC films with the highest concentration found after 20 days storage. The PE cling-film was shown to possess a simpler VOC profile, lacking some molecules peculiar to PVC films. The same conclusions can be drawn for cheeses wrapped in the PE cling-film. Other VOCs found in wrapped cheeses were likely to have been released either by direct transfer from the materials used for the manufacture of cling-films or from contamination of the films. Overall, HS-SPME is shown to be a rapid and solvent free technique to screen the VOCs profile of cling-films, and to detect VOCs migration from cling-films to cheese under real retail storage conditions.

Mechanism of aroma formation in white tea treated with solar withering.

Withering is a crucial process that determines the quality of white tea (WT). Solar withering (SW) is reported to contribute to the aroma quality of WT. However, the mechanism by which aroma is formed in WT subjected to SW remains unclear. In this study, through headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and transcriptomics, we found that 13 key genes enriched in the mevalonic acid and methylerythritol phosphate pathways, such as those of 1-deoxy-D-xylulose-5-phosphate synthase and terpineol synthase, were significantly upregulated, promoting the accumulation of α-terpinolene, geraniol, and nerolidol, which imparted floral and fruity odors to WT subjected to SW. Additionally, the significant upregulation of lipoxygenases enriched in the lipoxygenase pathway promoting the accumulation of hexanol, 1-octen-3-ol, (E, Z)-3,6-nonadien-1-ol, and nonanal, which contributed to the green and fresh odor in WT subjected to SW. This study provided the first comprehensive insight into the effect mechanism of SW on aroma formation in WT.

Determination of the thermal and physical properties of black tattoo ink using compound analysis.

Despite the widespread use of laser therapy in the removal of tattoos, comparatively little is known about its mechanism of action. There is a need for an improved understanding of the composition and thermal properties of the tattoo ink in order that simulations of laser therapy may be better informed and treatment parameters optimised. Scanning electron microscopy and time-of-flight secondary ion mass spectrometry identified that the relative proportions of the constituent compounds of the ink likely to exist in vivo are the following: carbon black pigment (89 %), carvacrol (5 %), eugenol (2 %), hexenol (3 %) and propylene glycol (1 %). Chemical compound property tables identify that changes in phase of these compounds lead to a considerable reduction in the density and thermal conductivity of the ink and an increase in its specific heat as temperature increases. These temperature-dependent values of density, thermal conductivity and specific heat are substantially different to the constant values, derived from water or graphite at a fixed temperature, which have been applied in the simulations of laser therapy as previously described in the literature. Accordingly, the thermal properties of black tattoo ink described in this study provide valuable information that may be used to improve simulations of tattoo laser therapy.

[Indoor air guide values for 2-ethylhexanol]. / Richtwerte für 2-Ethylhexanol in der Innenraumluft.

The German Ad-hoc Working Group on Indoor Guidelines of the Indoor Air Hygiene Committee and of the Supreme State Health Authorities is issuing indoor air guide values to protect public health. 2-Ethylhexan-1-ol (EH) is used amongst others as an intermediate in the production of plasticisers or as a flavouring agent in food, cosmetics and cleaning agents. EH is detectable in nearly all indoor air samples. Indoor air concentrations in Germany were reported to be in the range of 0.002 to 0.006 mg/m3 (median), the 95-percentiles were in the range of 0.009 to 0.03 mg/m3. Toxicity after acute exposure to EH is low. EH is irritating to skin and eyes after direct contact. Acute exposure of humans to 54 mg EH/m3 caused sensory irritation (NOAEC 8 mg EH/m3). In a subchronic inhalation study in rats, neither local nor systemic effects were detectable up to the highest concentration tested (638 mg/m3). EH is not genotoxic and not carcinogenic in rats and male mice after oral application. There is no evidence that EH impairs fertility. Developmental toxicity was only observed at doses, which already caused maternal toxicity (650 mg/kg bw/d). Sensory irritation is the most relevant effect for the derivation of indoor air guide values. Based on a LOAEC of 54 mg/m3 and a NOAEC of 8 mg/m3 in a short time (4 h) inhalation study with volunteers, and applying an intraspecies extrapolation factor of 10 and a factor of 6 for time extrapolation, a preliminary hazard-based guide value of 1 mg EH/m3 and a preliminary precautionary value of 0.1 mg EH/m3 have been derived.

Studies in search of selective detection of isomeric biogenic hexen-1-ols and hexanal by flowing afterglow tandem mass spectrometry using [H3O]+ and [NO]+ reagent ions.

RATIONALE: Plants emit a blend of oxygenated volatile C(6) compounds, known as green leaf volatiles (GLVs), in response to leaf tissue damage related to stress conditions. On-line chemical ionization mass spectrometry (CI-MS) techniques have often been used to study the dynamics of these emissions but they fail to selectively detect some important GLV compounds. METHODS: A flowing afterglow tandem mass spectrometer (FA-TMS) was used to investigate the feasibility of selective on-line detection of isomeric hexen-1-ols and hexanal. Product ions at m/z 101 and 83 from chemical ionization (CI) of these compounds by [H(3)O](+), and product ions at m/z 100, 99, 83, 82 and 72 from CI by [NO](+), have been subjected to collision-induced dissociation (CID) in the collision cell of the TMS at center-of-mass energies ranging between 0 and 9 eV. RESULTS: CID of product ions at m/z 101 and 83 from CI of GLVs with [H(3)O](+) and of product ions at m/z 83, 82 and 72 from CI of GLVs with [NO](+) resulted in identical fragmentation patterns for all measured compounds, ruling out any selectivity. However, CID of product ions at m/z 100 and 99 from CI by [NO](+) led to CID product ions with abundances differing largely between the compounds, allowing the fast selective detection of 2-hexen-1-ols, 3-hexen-1-ols and hexanal with a chosen accuracy within a well-defined range of relative concentrations. CONCLUSIONS: This research illustrates that, in contrast to common CI-MS techniques, FA-TMS allows the selective detection of hexanal in a mixture of hexanal and hexen-1-ols with a chosen accuracy for a well-defined range of relative concentrations and represents a step forward in the search for selective detection of GLVs in CI-TMS.

Evaluating headspace component vapor-time profiles by solid-phase microextraction with external sampling of an internal standard.

The vapor-time profiles of explosive materials are of valuable interest to Homeland Security, providing critical information that can aid in the detection of explosive-containing devices. An approach is described that achieves reproducible characterization of volatile components as a function of time based on comparison of the sample response to an externally sampled internal standard (ESIS). Utilizing nonequilibrium solid-phase microextraction (SPME) measurements, this SPME-ESIS technique improves reproducibility (reported as percent relative standard deviation) of vapor-time profiles by approximately an order of magnitude and allows for an equitable comparison of the target compound between diverse materials. Two odorants associated with canine detection of explosives, 2-ethyl-1-hexanol and 2,4-dinitrotoluene, are used to optimize parameters for the SPME-ESIS technique.

[Analysis of essential oil extracted from Lactuca sativa seeds growing in Xinjiang by GC-MS].

OBJECTIVE: To analyze the components of essential oil from Lactuca sativa seeds growing in Xinjiang. METHODS: The components of essential oil from Lactuca sativa seeds were analyzed by gas chromatography-mass spectrometry (GC-MS). RESULTS: 62 components were identified from 71 separated peaks,amounting to total mass fraction 95.07%. The dominant compounds were n-Hexanol (36.31%), n-Hexanal (13.71%), trans-2-Octen-l-ol (8.09%) and 2-n-Pentylfuran (4.41%). CONCLUSION: The research provides a theoretical basis for the exploitation and use of Lactuca sativa seeds resource.

Characterization of key odor-active compounds in sweet Petit Manseng (Vitis vinifera L.) wine by gas chromatography-olfactometry, aroma reconstitution, and omission tests.

Petit Manseng (Vitis vinifera L.) has become a popular variety in China for the production of semisweet and sweet wines. However, few studies focused on investigating the molecular odor code of its key odorants. In this study, the key odor-active compounds of Chinese sweet Petit Manseng wine were identified by gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). Fifty-five odorous zones were sniffed and identified by application of aroma extraction dilution analysis on a distillate prepared by liquid-liquid extraction and solvent-assisted flavor evaporation. Among them, isoamyl alcohol, ethyl octanoate, isovaleric acid, (E)-ß-damascenone, and phenylethanol particularly displayed with highest flavor dilution factors above 1024. The quantification of volatiles by headspace solid-phase microextraction coupled with GC-MS and GC coupled with triple quadrupole MS/MS and a calculation of odor activity values (OAVs) indicated 23 volatiles with OAVs above 1. Ethyl hexanoate showed the highest OAV with 208.8, followed by (E)-ß-damascenone (189.0), 3-mercaptohexanol (60.3), isoamyl acetate (45.4), and furaneol (40.1). The aroma of the sweet wine was successfully reconstituted by combining 42 aroma compounds in a model wine solution. 3-Mercaptohexanol, (E)-ß-damascenone, furaneol, γ-octalactone + γ-decalactone + γ-hexalactone, and ethyl cinnamate had important influence on the aroma of sweet Petit Manseng wine assessed by omission tests. Moreover, the discrimination of wines from three regions was successfully achieved by partial least squares discriminant analysis based on quantitative results of key odorants. 3-Mercaptohexanol was considered as the most responsible for the region discrimination and had highest concentrations in Petit Manseng wines from Jiaodong Peninsula. PRACTICAL APPLICATION: Understanding of the knowledge in key odorants of Petit Manseng wines could be useful to improve wine quality through viticultural and enological practices.

Immunotoxicity activity of the major essential oil of Filipendula glaberrima against Aedes aegypti L.

The aerial parts of Filipendula glaberrima were extracted and the composition and immunotoxicity effects of major essential oils were studied. The analyses conducted by gas chromatography and mass spectroscopy (GC-MS) revealed the essential oils of F. glaberrima. The F. glaberrima essential oil (FGEO) yield was 0.046%, and GC/MS analysis revealed that its major constituents were ß-farnesol (2.96%), l-α-terpineol (2.43%), benzenemethanol (2.87%), (Z)-3-hexen-1-ol (5.23%), and 2,6-bis(1,1-dimethylethyl)-4-methylphenol (1.91%). The essential oil had a significant toxic effect against early fourth stage larvae of Aedes aegypti L with an LC(50) value of 28.43 ppm and an LC(90) value of 76.21 ppm. The results could be useful in search for newer, safer, and more effective natural immunotoxicity agents against A. aegypti.

[Analysis of essential oil from Mahonia duclouxiana].

OBJECTIVE: To analyze the compositions of essential oil from Mahonia duclouxiana. METHODS: The essential oil was extracted by steam distillation, its chemical components were analyzed by GC-MS, and principal component was confirmed by GC. RESULTS: 80 peaks were detected and 41 components have been identified, which made up more than 90% of total essential oil. The major component was 4-Terpineol (43.73%), the other high content components were alpha-Terpineol (5.23%), (Z)-3-Hexen-1-ol (4.78%), Linalool (4.04%), etc. CONCLUSION: The chemical components of essential oil of from Mahonia duclouxiana by GC-MS for the first time. This study provided science basis for further research development of Mahonia duclouxiana.

Characterization of the effect of cis-3-hexen-1-ol on green tea aroma.

cis-3-Hexen-1-ol has been regarded as the main source of green aroma (or green odor) in green tea. However, no clear findings on the composition of green aroma components in tea and the effect of cis-3-hexen-1-ol on other aroma components have been reported. In this study, the main green aroma components in green tea were characterized, especially the role of cis-3-hexen-1-ol in green aroma was analyzed and how it affected other aroma components in green tea was studied. Based on the GC-MS detection, odor activity value evaluation, and monomer sniffing, 12 green components were identified. Through the chemometric analysis, cis-3-hexen-1-ol was proven as the most influential component of green aroma. Moreover, through the electronic nose analysis of different concentrations of cis-3-hexen-1-ol with 25 other aroma components in green tea, we showed that the effect of cis-3-hexen-1-ol plays a profound effect on the overall aroma based on the experiments of reconstitution solution and natural tea samples. GC-MS and CG-FID confirmed that the concentration range of the differential threshold of green odor and green aroma of cis-3-hexen-1-ol was 0.04-0.52 mg kg-1.