Analysis of odour compounds from scented consumer products using gas chromatography-mass spectrometry and gas chromatography-olfactometry

Scented consumer products are being bought in increasing amounts and gaining more popularity. There is, however, relatively little information available about their ingredients, emissions and allergenic potential. Frequently, a mixture of different fragrance substances and not solely an individual substance contributes to the overall desired smell. The aim of this study was to investigate the odorous volatile organic compounds (OVOCs) in consumer products containing fragrances. Over 44 products were selected: various scented candles, printing products with different scent types and other products types particularly meant to be used indoors. Measurements were carried out in a desiccator. Air samples were collected on thermal desorption tubes to determine the released fragrance substances by means of gas chromatography-mass spectrometry (GC-MS). Moreover, gas chromatography-olfactometry (GC-O) was used to obtain sensory data and to ensure no important odorant was overlooked. Using both methods it was possible to distinguish between odour active and inactive compounds and subsequently to identify almost 300 different odorants across all scented products. Besides the advantage of differentiation, as the human nose is a very sensitive detector, GC-O was found to be a useful tool for detecting traces and chosen target compounds. One focus in this study lay on the 26 EU-regulated fragrance allergens to prove their relevance in scented consumer goods. In total, 18 of them were identified, with at least one substance being present in almost every product. Benzyl alcohol, cinnamaldehyde, citronellol, eugenol, linalool and limonene were the prevalently detected allergens. Particularly linalool and limonene were observed in over 50% of the products. In addition, eugenol appeared to be one of the most frequently detected compounds in trace-level concentrations in the candle emissions.     

Determination of suspected fragrance allergens in cosmetics by matrix solid-phase dispersion gas chromatography-mass spectrometry analysis

An effective low cost sample preparation methodology for the determination of regulated fragrance allergens in leave-on and rinse-off cosmetics has been developed applying, for the first time, matrix solid-phase dispersion (MSPD) to this kind of analytes and samples. The selection of the most suitable extraction conditions was made using statistical tools such as ANOVA, as well as a factorial multifactor experimental design. These studies were carried out using real cosmetic samples. In the final conditions, 0.5 of sample, previously mixed with 1g of anhydrous Na(2)SO(4), were blended with 2g of dispersive sorbent (Florisil), and the MSPD column was eluted with 5 mL of hexane/acetone (1:1). The extract was then analyzed by GC-MS without any further clean-up or concentration step. Accuracy, precision, linearity and detection limits (LODs) were evaluated to assess the performance of the proposed method. Quantitative recoveries (>75%) were obtained and RSD values were lower than 10% in all cases. The quantification limits were well below those set by the international cosmetic regulations, making this multi-component analytical method suitable for routine control. In addition, the MSPD method can be implemented in any laboratory at low cost since it does not require special equipment. Finally, a wide variety of cosmetic products were analyzed. All the samples contained several of the target cosmetic ingredients, with and average number of seven. The total fragrance allergen content was in general quite high, even in baby care products, with values close to or up to 1%, for several samples, although the actual European Cosmetic Regulation was fulfilled.     

Direct identification of prohibited substances in cosmetics and foodstuffs using ambient ionization on a miniature mass spectrometry system

Significantly simplified work flows were developed for rapid analysis of various types of cosmetic and foodstuff samples by employing a miniature mass spectrometry system and ambient ionization methods. A desktop Mini 12 ion trap mass spectrometer was coupled with paper spray ionization, extraction spray ionization and slug-flow microextraction for direct analysis of Sudan Reds, parabens, antibiotics, steroids, bisphenol and plasticizer from raw samples with complex matrices. Limits of detection as low as 5 μg/kg were obtained for target analytes. On-line derivatization was also implemented for analysis of steroid in cosmetics. The developed methods provide potential analytical possibility for outside-the-lab screening of cosmetics and foodstuff products for the presence of illegal substances.     

气相色谱-串联质谱法同时测定化妆品中28种香料成分北大核心CSCD

随着化妆品种类的日益增多,化妆品中的香精香料成分受到了越来越多人的关注,建立化妆品中香精香料成分的分析测定方法是消除人们担忧最有效的措施之一。该研究建立了气相色谱-串联质谱(GC-MS/MS)同时测定化妆品中28种香料残留的方法。样品由甲醇提取,含油脂较多的经中性氧化铝固相萃取小柱净化,色素多、基质复杂的由QuEChERS净化,待测物采用GC-MS/MS测定,以保留时间和特征离子对定性,外标法定量。实验结果表明,分析物质的检出限(S/N=3)为2~20μg/kg,定量限(S/N>10)为5~50μg/kg。28种物质分别在1~100、2~200、4~200、10~1 000μg/L范围内线性关系良好,分析物质的线性相关系数(r^(2))>0.999。在空白样品中添加28种香料,添加水平为50~500μg/kg时,回收率范围为71.3%~120.4%, RSD范围为1.5%~14.6%。该方法可对28种香料成分进行准确测定,不但可以有效排除复杂基体的干扰,而且简单、灵敏、稳定,能够很好地应用于化妆品中香料的含量测定。通过该方法对16种化妆品中的香精香料成分进行测定,发现12种化妆品中均检出相关香料成分,说明化妆品中的香精香料安全应引起重视。     

Rapid determination of floral aroma compounds of lilac blossom by fast gas chromatography combined with surface acoustic wave sensor

A novel analytical method using fast gas chromatography combined with surface acoustic wave sensor (GC/SAW) has been developed for the detection of volatile aroma compounds emanated from lilac blossom (Syringa species: Syringa vulgaris variginata and Syringa dilatata). GC/SAW could detect and quantify various fragrance emitted from lilac blossom, enabling to provide fragrance pattern analysis results. The fragrance pattern analysis could easily characterize the delicate differences in aromas caused by the substantial difference of chemical composition according to different color and shape of petals. Moreover, the method validation of GC/SAW was performed for the purpose of volatile floral actual aroma analysis, achieving a high reproducibility and excellent sensitivity. From the validation results, GC/SAW could serve as an alternative analytical technique for the analysis of volatile floral actual aroma of lilac. In addition, headspace solid-phase microextraction (HS-SPME) GC-MS was employed to further confirm the identification of fragrances emitted from lilac blossom and compared to GC/SAW.     

Determination of 48 fragrance allergens in toys using GC with ion trap MS/MS

This paper presents a method for the simultaneous determination of 48 fragrance allergens in four types of toys (plastic toys, play clays, plush toys, and paper toys) based on GC with ion trap MS/MS. Compared with single‐stage MS, MS/MS is superior in terms of the qualification and quantification of a large range of compounds in complicated matrices. Procedures for extraction and purification were optimized for each toy type. The method proved to be linear over a wide range of concentrations for all analytes with correlation coefficients between 0.9768 and 0.9999. Validation parameters, namely, LODs and LOQs, ranged from 0.005–5.0 and from 0.02–20 mg/kg, respectively. Average recoveries of target compounds (spiked at three concentration levels) were in the range of 79.5–109.1%. Intraday and interday repeatabilities of the proposed method varied from 0.7–10.5% and from 3.1–13.4%, respectively. The proposed method was used to monitor fragrance allergens in commercial toy products. Our findings indicate that this method is an accurate and effective technique for analyzing fragrance allergens in materials composed of complex components.     

Trace detection of hormones and sulfonamides in viscous cosmetic products by neutral desorption extractive electrospray ionization tandem mass spectrometry

A sensitive method based on a geometry-independent neutral desorption (GIND) in combination with extractive electrospray ionization mass spectrometry (EESI-MS) has been developed for fast detection of illicit additives such as sulfonamides and hormones in highly viscous cosmetic products. The method gave a low limit of detection (LOD) (in the range of 0.001-1 ng/g), acceptable relative standard deviation (RSD=6.8-11.4%) and reasonable recovery (87-116%) for direct measuring of nine types of hormones and sulfonamides in the cosmetic products. The average measurement time for two types of samples was less than 1 min. Trace amounts of analytes in commercial cosmetic products have been quantitatively detected, without any sample pretreatment. The experimental results showed that non-volatile illicit additives such as sulfonamides and hormones could be sensitively liberated using the GIND device for quantitative detection from the highly viscous cosmetic products, demonstrating that GIND-EESI-MS is a promising tool for high throughput, sensitive and quantitative analysis of highly complex viscous samples.     

Application of response function methodology for the simultaneous determination of potential fragrance allergens and preservatives in personal care products using micellar electrokinetic chromatography

A micellar electrokinetic chromatography method was developed for determination of 15 suspected fragrance allergens and preservatives. The target compounds are widely used as ingredients in many personal care products, and all of them are included in the European Regulation concerning cosmetic products. The method was optimized by using a central composite experimental design and response surface methodology. A modified chromatographic response function was defined to weigh the terms in the response function adequately. After optimization of experimental conditions, a background electrolyte of 100 mM sodium dodecyl sulphate and 24 mM sodium tetraborate and pH 9.0 was selected for the separation of the analytes. The developed methodology was evaluated in terms of linearity, limits of detection and quantification, precision and accuracy, showing appropriate values (i.e., R ²?=?≥0.99 and accuracy of 89–115 %). Finally, applicability of the micellar electrokinetic chromatography method was assessed by successfully quantifying fragrance allergens and preservatives in commercial personal care products. The most commonly found analyte was linalool (48.3 % of samples) followed by benzoic acid (37.6 %). All samples contained at least one of the target compounds, thus confirming the ubiquity of fragrance allergens and preservatives in personal care products.

Identification of organic colourants in cosmetics by HPLC-diode array detection

Summary A method for the analysis of organic cosmetic colourants was developed. The colourants extracted from the cosmetic products were analysed by HPLC followed by diode-array detection across the wavelength range 275 nm–760 nm. The chromatographic separation was performed on a column with a polymeric packing using gradient elution with a mobile phase composed of citrate buffer, the ion-pairing reagent tetrabutylammonium hydroxide, acetonitrile and tetrahydrofuran. The colourants were identified on the basis of their retention times as well as their UV-visible spectra. A spectral library consisting of retention times and UV-visible spectra of 130 organic cosmetic colourants has been built for the purpose of identifying of colouring matter in cosmetic products. Solid-phase extraction methods using C-18 silica and aminobonded silica have been developed for the extraction of colourants from various types of cosmetic products. The method for the identification of colourants in nail varnishes and lipsticks has been optimized for routine analysis. Presented at the 21^st ISC held in Stuttgart, Germany, 15^th–20^th September, 1996     

Determination of coumarin in fragrance products by capillary gas chromatography with electron capture detection.

A gas chromatographic (GC) method is described for the determination of coumarin in fragrance products. Coumarin was tentatively identified by retention time and confirmed by GC/mass spectrometry. The amount of coumarin was determined by external standard. The method was validated by conducting recovery studies from fortified fragrance products at several concentrations. Recoveries of coumarin ranged from 99 to 110%, with a relative standard deviation of 3.24. The method was used to survey a variety of fragrance products purchased in the metropolitan Washington, DC area, for coumarin. Seventy one percent of the products were found to contain coumarin at concentrations ranging from 0.002 to 0.61%.     

Electrochemical Reduction of a Conjugated Cinnamic Acid Diazonium Salt as an Immobilization Matrix for Glucose Biosensor

Initial results on the synthesis of a new conjugated diazonium salt of trans‐4‐cinnamic acid diazonium fluoroborate, which is used for the chemical modification of the glassy carbon (GC) electrode with trans‐4‐cinnamic acid groups through electrochemical reduction, and direct covalent immobilization of glucose oxidase (GOD) on the cinnamic acid groups are presented. The chemically modified GC electrode exhibits a good selectivity relative to the bare GC electrode for the various possible interfering compounds in glucose analysis: namely ascorbic acid and 4‐acetamidophenol. Covalent immobilization of GOD on the chemically modified GC electrode produces a biosensor which responds to glucose concentration changes in the presence of a soluble redox mediator (ferrocenemethanol). The chemical modification of GC by cinnamic acid groups is potentially useful for the attachment of other enzymes and biochemical reagents.     

Multicomponent analytical methodology to control phthalates, synthetic musks, fragrance allergens and preservatives in perfumes

A simple, fast, robust and reliable multicomponent analytical method applicable in control laboratories with a high throughput level has been developed to analyze commercial brands of perfumes. Contents of 52 cosmetic ingredients belonging to different chemical families can be determined in a single run. Instrumental linearity, precision of the method and recovery studies in real samples showed excellent results, so that quantification by external calibration can be effectively applied. Relevant limits of detection and quantification were obtained for all the targets considered, far below the legal requirements and amply adequate for its accurate analytical control.A survey of 70 commercial perfumes and colognes has been performed, in order to verify whether these products complied with the recent changes in European legislation: regarding the maxima allowed concentrations of the ingredients and/or ingredient labelling. All samples contained some of the target ingredients. Several samples do not comply with the regulations concerning the presence of phthalates. Musks data confirmed the trend about the replacement of nitromusks by polycyclic musks; as well as the noticeable introduction of macrocyclic musks in the perfumes composition. The prohibited musk moskene has been detected in one sample in an appreciable concentration. The average number of fragrance allergens is twelve per sample; their presence must be indicated in the list of ingredients when its concentration exceeds the 0.001%, but values higher than 1% have been found in some samples. Preservatives data show that parabens, although ubiquitous in other cosmetic products, are not widely used in perfumery. In contrast, the presence of BHT is indeed widespread. The degree of compliance with the European Regulation on the labelling has been evaluated in a subset of samples, and only about the 38% of the perfumes were properly labelled for the allergens tested.     

A method for the analysis of intermediates of oxidative hair dyes in cosmetic products

A method has been developed and validated for the analysis of some commonly used intermediates of oxidative hair dyes: phenylenediamines, toluenediamines, aminophenols, 1-Naphthol, resorcinol, and hydroquinone. The target analytes are ion-paired prior to HPLC analysis with gradient elution employing phosphate buffer-acetonitrile as mobile phase and detection in the wavelength range 220–400 nm by a photodiode array detector. A spectral-library, consisting of 220–400 nm spectra of the target substances and their HPLC retention times, has been prepared for the identification. A method of sample preparation was established and applied to the analysis of a series of cosmetic formulations for hair dyeing. The method has been found to be suitable for routine analysis of the target intermediates of oxidative hair dyes, and it may also be suitable for the analysis of some non-target intermediates of these substances.     

Development of a method based on sorbent trapping followed by solid-phase microextraction for the determination of synthetic musks in indoor air

Synthetic musks are extensively used as fragrance components in a wide range of consumer and personal care products such as detergents, shampoos, perfumes and other cosmetic products. Amongst them, galaxolide and tonalide have become ubiquitous pollutants due to their continuous releasing into the environment. Because of their nature as artificial fragrances, inhalation should be considered as an important exposure pathway, especially in indoor environments. However, up to now very few studies have been carried out to determine these emergent pollutants indoors. In this work, a simple and highly sensitive methodology for the analysis of synthetic musk fragrances in indoor air samples is presented. The proposed methodology combines solid-phase extraction (SPE) and solid-phase microextraction (SPME), followed by gas chromatography-mass spectrometry (GC/MS). To the best of our knowledge, this is the first method based on SPME for the analysis of musks in air. By active sampling, musks present in air were adsorbed onto 25mg Tenax and then transferred to a SPME fiber in the headspace mode (HS). An experimental design strategy was used to optimize main factors potentially affecting the microextraction process such as fiber coating, temperature and the addition of a microvolume of organic solvent to the solid sorbent prior to SPME. Breakthrough of the SPE sorbent was studied from 1 to 10m(3) without significant losses. Recovery studies were performed at two concentration levels (2 and 20ngm(-3)), obtaining quantitative recoveries (>/=85%) by external calibration. A comprehensive study was performed in order to estimate the limits of detection taking into account the contamination risks and laboratory blanks. Values at the sub ngm(-3) level were achieved for all the target compounds sampling 5m(3) air. External calibration, not requiring the complete sampling process, demonstrated to be suitable for the quantification of all musk compounds. Finally, several indoor environments were analyzed using the proposed method.     

Terpenes to Ionic Liquids: Synthesis and Characterization of Citronellal-Based Chiral Ionic Liquids

A series of new chiral ionic liquids have been prepared and characterized starting from a simple, economical, and commercially available monoterpene, citronellal. The aldehyde functionality in citronellal is converted into a Schiff base using an amine, followed by reduction with Raney nickel to give the desired quaternary amine. Most of the ionic liquids generated using this procedure are found to be liquids at room temperature.     

Characterisation of flavour compounds formed by γ-irradiation of polypropylene

Sterilisation of plastic packaging materials for food, pharmaceutical or cosmetic products with ⁶⁰Co γ-irradiation in the presence of oxygen can result in the formation of volatile substances. These may subsequently induce off-odours in these materials that might be regarded as negative by the consumers. Trace volatiles and odorous substances of polypropylene, irradiated with ⁶⁰Co γ rays at 10 and 20 kGy, respectively, were collected and analysed by gas chromatography–olfactometry (GC–O), GC–MS and GC–GC–MS. The methodology was successfully applied for identification of 29 characteristic odorants in a non-irradiated control sample and 38 odorants in γ-irradiated polypropylene samples. Selected odour-active compounds were quantified using GC–GC–MS in combination with stable isotope dilution assays. The quantitative data mirrors the compositional changes in volatile odorous substances from polypropylene during treatment with ionising γ rays in a ⁶⁰Co-irradiation plant.     

Catalyst-controlled inverse-electron-demand hetero-Diels-Alder reactions in the enantio- and diastereoselective synthesis of iridoid natural products

[reaction: see text] Iridoid natural products 1-4 are accessed stereoselectively by means of tridentate (Schiff base)Cr(III)-catalyzed hetero-Diels-Alder reactions between ethyl vinyl ether and enantioenriched 5-methyl-1-cyclopentene-1-carboxaldehyde. An efficient route to the aldehyde from citronellal is afforded by the ring-closing metathesis reaction.     

超高效液相色谱-串联质谱法测定化妆品中新型糖皮质激素氯倍他索乙酸酯

采用超高效液相色谱-串联质谱法建立了化妆品中氯倍他索乙酸酯的检测方法,适用于膏霜乳类、凝胶类、泥类、贴膜类和液体(水)类5种常见化妆品基质。对影响被测物质的前处理方法、提取溶剂、提取时间等因素和色谱、质谱条件等进行了考察。最终建立方法为样品经乙腈涡旋分散、超声提取、过滤后用超高效液相色谱-串联质谱仪测定,采用Waters CORTECS C₁₈色谱柱(150 mm×2.1 mm, 2.7 μm),以水和乙腈作为流动相分离,在电喷雾正离子模式(ESI⁺)下,以多反应监测(MRM)方式采集,采用基质匹配标准曲线进行定量分析。5种基质类型下,被测物质在0.9~37 μg/L的范围内线性拟合良好,线性相关系数(R²)均超过0.99。方法的检出限为0.03 μg/g,定量限为0.09 μg/g。在定量限、2倍定量限和10倍定量限3个水平下的加标回收率试验中,被测物质在5种基质中的回收率范围为83.2%~103.2%,相对标准偏差(RSD, n=6)范围为1.4%~5.6%。采用该方法对不同基质类型的化妆品样品进行筛查,共发现5批阳性样品,其中氯倍他索乙酸酯的含量范围为1.1~48.1 μg/g。该方法操作简单,灵敏可靠,适用于不同基质类型化妆品的高通量定性定量筛查分析,为监测化妆品中的非法添加提供了技术支持及理论依据。     

Element-selective detection using capillary gas chromatography with atomic emission detection

Capillary GC coupled to an atomic emission detector (AED) provides a powerful new hyphenated technique for the separation and characterization of complex mixtures and compounds. The AED provides simultaneous and truly specific multi-element detection. The specificity of detection reduces the need for the complex sample pretreatment procedures which are necessary to reduce the interference from co-eluted substances which is experienced with detectors such as the FID and the ECD. A range of environmentally significant problems has been studied, including PCB analysis, the characterization of the reaction products of a novel waste treatment process, and the profiling of sulfur-containing species formed by the pyrolysis of various types of coal.     

Sorbent trapping solid-phase microextraction of fragrance allergens in indoor air

Exposure to fragrance substances is exponentially increasing in our daily life due to the enhanced use of scented products. Some fragrances are known to be important sensitizers, inhalation being an important exposure pathway in indoor environments. A simple and sensitive method based on solid-phase enrichment and solid-phase microextraction (SPME) followed by gas chromatography–mass spectrometry (GC–MS) has been developed for the analysis of 24 volatile fragrance allergens in indoor air. Suspected allergens present in the air (0.2 m³) were adsorbed onto a very small quantity of florisil (25 mg) and then transferred to a SPME fiber in the headspace mode (HS). To the best of our knowledge, this paper describes the first application of SPME for the determination of these compounds in air samples. The experimental parameters affecting the microextraction process have been optimized using a multifactor experimental design strategy. Accuracy, linearity, precision and detection limits (LODs) were evaluated to assess the performance of the proposed method. External calibration, using spiked sorbent standards, and not requiring the complete sampling process (only the SPME step), demonstrated to be suitable for the quantification of all suspected allergens. Recovery studies were performed at three concentration levels (0.04, 1.00 and 50 μg m⁻³), obtaining quantitative recoveries (≥85%) in most cases. LOD values at the low ng m⁻³ level were achieved for all the target compounds. The application of the method to daily home air samples demonstrated the ubiquity of this kind of fragrance ingredients in quotidian indoor environments, finding 18 of the 24 considered compounds in concentrations ranging from 0.01 to 56 μg m⁻³. Benzyl alcohol, linalool, citronellol, ionone and lilial were found in most analyzed samples.