Identification and quantification of the migration of chemicals from plastic baby bottles used as substitutes for polycarbonate

The results of a study on the analytical identification and quantification of migration of chemicals from plastics baby bottles found in the European Union market made of materials that are now present as substitutes for polycarbonate (PC) are reported. A total of 449 baby bottles with a focus on first age or sets of bottles were purchased from 26 European Union countries, Canada, Switzerland and the USA. From this collection, which contained several duplicates, a total of 277 baby bottles were analysed. The materials included different types of plastic such as PC, polyamide (PA), polyethersulphone (PES), polypropylene (PP), but also silicone, and from the United States a co-polyester marketed under the trade name Tritan?. The bottles were subjected to the conventional migration test for hot fill conditions, i.e. 2?h at 70°C. The simulant used was that specified in European Union legislation (2007/19/EC) for milk, i.e. 50% ethanol. In a first phase 1, migration was conducted since the scope of this investigation was a screening rather than a true compliance testing check. Second and third migrations were performed on selected articles when migrated substances exceeded limits specified in the legislation. In order to verify some materials, a portion of the bottle was cut to run an FT-IR fingerprint to confirm the nature of the polymer. The migration solutions in general showed a low release of substances. Results showed that bottles made of PP and silicones showed a greater number of substances in the migration solutions and in greater quantity. Chemicals from PP included alkanes, which could be found in >65% of the bottles at levels up to 3500?µg?kg^?1; and benzene derivatives in 17% of the baby bottles and found at levels up to 113?µg?kg^?1. Some substances were found on a regular basis such as plasticisers, esters and antioxidants (e.g. tris(2,4-di-tert-butylphenyl)phosphate, known as Irgafos 168. Some substances found were not included in the Community positive list, which means that those should not be found even in the first migration. Such substances included 2,6-di-isopropylnaphthalene (DIPN), found in 4% of the bottles at levels up to 25?µg?kg^?1, 2,4-di-tert-butyl phenol (in 90% of the bottles at levels up 400?µg?kg^?1). Moreover, bisphenol A (BPA) was detected and quantified in baby bottles made of PA, but limited to one brand and model specific (but labelled BPA free). Results for baby bottles made of silicone also indicated the presence of components, e.g. potentially coming from inks (benzophenone, diisopropyl naphtahalene – DIPN, which could come for example from the presence of instruction leaflets in the bottles). In the case of silicone, phthalates were also found in relevant concentrations, with levels for DiBP and DBP from the first migration test of 50–150?µg?kg^?1 and DEHP at levels 25–50?µg?kg^?1.     

静态顶空-气相色谱质谱联用法测定进出口油脂中的四种苯系物污染

采用静态顶空技术和气相色谱质谱仪(GC-MS)联用,检测了进出口油脂中苯、甲苯和二甲苯等苯系物的污染。探讨了色谱柱、恒温温度、平衡时间对测定结果的影响。结果表明,采用HP-5色谱柱,样品恒温温度为90℃,平衡时间为40min时,目标化合物测定效果好。方法检出限小于0.04mg/kg,添加回收率在89.4%(邻二甲苯)～112.5%(甲苯)之间。相对标准偏差(RSD)小于12.4%。该法具有操作简单、能够准确定性、灵敏度较高的特点。     

Authentication analysis of cod liver oil from beef fat using fatty acid composition and FTIR spectra

This study aimed to authenticate cod liver oil (CLO) from beef fat (BF) by determining the level of BF as a fat adulterant in CLO. Two instrumental techniques, namely GC-FID for fatty acid analysis and Fourier transform infrared (FTIR) spectroscopy, were exploited for such authentication. The decreased level of some fatty acids, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), could be used as an indicative means to detect the adulteration of CLO with BF. In addition, FTIR spectroscopy combined with partial least-squares (PLS) at frequency regions of 1200–1000?cm^?1 was successfully developed for the quantification of BF in CLO. Using the PLS model, the errors obtained in calibration and prediction samples were 0.55% and 0.82% v/v, respectively.     

食用油脂鉴伪技术研究进展

近年来,地沟油事件多次引起人们对我国食品安全现状的担忧。由于缺乏有效的食用油脂中地沟油鉴别检测技术,制约着相关方面的食品安全监管和预警体系建设。由于地沟油通常是作为一种添加物掺入食用油脂中,更有甚者,地沟油渣直接冒充正常油脂流向餐桌,因此食用油脂鉴伪技术研究对地沟油的检测有较大借鉴作用。基于此,该文对近几年来食用油脂鉴伪技术研究进展进行综述。     

纺织品禁用偶氮染料检测色谱条件优化

本方法针对纺织品禁用偶氮染料检测中常用的GC/MS色谱柱进行了检测条件的优化,大大提高了检测效率。有利于日常检测中对纺织品偶氮染料的快速检测。     

食用油脂中特丁基对苯二酚气相色谱测定方法

建立了食用油脂中特丁基对苯二酚(TBHQ)的气相色谱测定方法.根据TBHQ溶解于乙醇的性质,利用80%乙醇溶液将油脂中TBHQ提取出来,采用气相色谱法对其进行测定.TBHQ在0～250μg/mL浓度范围内线性良好,相关系数0.9999,最低检出限为0.001g/kg,按0.05、0.10和0.20g/kg三个添加水平测定回收率在91.9%～98.0%之间, 7次重复测定的变异系数在3.9%～5.9 %之间,与液相色谱法相比较,采用F检验法对实际样品进行了检验,结果表明两方法没有显著性差异.     

液相色谱法测定油脂及其制品中苯并(a)芘含量

目的 建立液相色谱法测定油脂及其制品中苯并(a)芘的方法。方法 试样经过正己烷提取, 中性氧化铝或分子印迹小柱净化, C18色谱柱分离, 荧光检测器检测。结果 方法的线性范围为0.5~20 μg/L, 线性相关系数为0.9999, 最低定量浓度(the limit of quantity, LOQ)为0.5 μg/kg, 在0.5、5、15 μg/kg 3个添加水平下平均回收率为75.5%~93.8%, 相对标准偏差(relative standard deviation, RSD)为3.0%~9.6%。结论 该方法准确度与精密度满足GB/T 27404规定, 定量限满足GB 2762实施要求, 被用于修订GB/T 5009.27-2003为 GB 5009.27-2016。     

Baseline levels of melamine in food items sold in Canada. I. Dairy products and soy-based dairy replacement products

A variety of dairy and soy-based dairy replacement products (n = 246) purchased from Canadian retail outlets were analysed for baseline levels of melamine (MEL) using a sensitive LC–MS/MS method (method quantification limit = 4 µg/kg). MEL was infrequently detected; only 14% of the items analysed contained quantifiable levels of MEL. The concentrations observed, aside from one recalled sample of candy, ranged from 0.00435 to 0.276 mg/kg, and were at least 10 times lower than the 2.5 mg/kg interim standard for melamine in products containing milk and milk-derived ingredients established by Health Canada. The consumption of foods containing these low levels of MEL does not constitute a health risk for consumers.     

Baseline levels of melamine in food items sold in Canada. II. Egg,soy, vegetable,fish and shrimp products

A variety of egg-containing, soy-based, fish, shrimp and vegetable products sold in Canada were analysed for melamine (MEL) using a sensitive solid-phase extraction LC–MS/MS analytical method. MEL was detected above the method quantification limit of 0.004 mg/kg in 98 of the 378 samples analysed. Concentrations in the various food product groups ranged 0.00507–0.247 mg/kg (egg-containing items), 0.00408–0.0479 mg/kg (soy-based meat substitutes), 0.00409–1.10 mg/kg (fish and shrimp products), and 0.00464–0.688 mg/kg (vegetable products). MEL was detected less frequently in egg- and soy-containing products. The presence of MEL in most of the Canadian Total Diet Study shrimp composites collected after 2001 suggested the residues in shrimp were caused by a relatively recent exposure to MEL. All concentrations of MEL reported were lower than the 2.5 mg/kg interim standard established for MEL in items containing milk and milk-derived ingredients and the respective maximum residue limits for cyromazine and its metabolite, melamine, in vegetables set by the Canadian Government (2009; http://www.hc-sc.gc.ca/fn-an/securit/chem-chim/melamine/qa-melamine-qr-eng.php#8). The consumption of foods containing these low levels of MEL does not constitute a health risk for consumers.     

测定油脂极性组分不同柱层析技术的比较

以现行的油脂极性组分检测ISO 8420(2002)为依据,对GB/T 5009.202—2003《食用植物油煎炸过程中的极性组分(PC)的测定》的柱层析法,GB 5009.202—2016《食品安全国家标准食用油中极性组分(PC)的测定》中的制备型快速柱层析法和柱层析法进行比对实验。结果发现:GB/T 5009.202—2003的柱层析法的检测结果与ISO标准的检测结果差异较大,一致性差;而GB 5009.202—2016中的制备型快速柱层析法和柱层析法的检测结果与ISO标准的检测结果基本一致。     

高效液相色谱法同时检测食品中安赛蜜、苯甲酸、山梨酸、糖精钠的影响因素分析

目的分析高效液相色谱法(high performance liquid chromatography,HPLC)检测食品中安赛蜜、苯甲酸、山梨酸、糖精钠等添加剂含量时的各种影响因素。方法从流动相比例、流动相pH、样品基质、流动相乙酸铵浓度、柱温、标准曲线溶液储存时间等方面判断各因素对色谱分析结果的影响。结果随流动相中乙酸铵浓度降低,柱温升高,4种物质的保留时间缩短,其中乙酸铵的浓度对糖精钠的影响最大。流动相pH对安赛蜜和糖精钠保留时间无影响,而苯甲酸和山梨酸随流动相pH升高保留时间缩短,其对山梨酸影响最大。样品pH对保留时间有影响,但并不影响分析结果。乙醇含量对保留时间无影响,标准曲线溶液4℃冰箱密封保存,一周内各浓度峰面积变化不显著(P0.05)。结论安赛蜜、苯甲酸、山梨酸、糖精钠分析会受各种色谱条件影响,标准曲线溶液4℃冰箱密封保存一周内有效。     

Migration analysis of epoxidized soybean oil and other plasticizers in commercial lids for food packaging by gas chromatography–mass spectrometry

A modification of the method of Castle et al. (J. Chromatogr. 1988: 437:274–280) for the analysis of epoxidized soybean oil (ESBO) is proposed to simplify the analysis and reduce the time and consumption of reagents. The proposed modifications, particularly the elimination of the internal standard, resulted in a simpler, faster and more economical method. A complete analytical validation, including evaluation of the main analytical parameters, such as detection and quantification limits, linearity, working range, precision, accuracy and selectivity, was carried out. The data demonstrated the suitability of the proposed method for the determination of ESBO in polymer matrices. A specific migration study for ESBO in different food simulants (fat and aqueous) was carried out by applying the method to poly(vinyl chloride) materials prepared with known amounts of ESBO, as well as some commercial lids. High levels of migration of ESBO into fat simulants were found. In the case of commercial lids, in addition to ESBO, some other plasticizers such as citrates, adipates and sebacates were found and quantified to establish their migration under different conditions of use.     

Analysis of the volatile components of tea seed oil (Camellia sinensis O. Ktze) from China using HS‐SPME‐GC/MS

Tea seed oil is unique to Asia and boasts significant nutritional and health benefits. In this study, the volatile components of tea seed oil from eight major producing areas in China were analysed using HS‐SPME‐GC/MS. The comparison was made among them to obtain their characteristic volatile compounds. After fibre selection and extraction and desorption condition optimisation, 194 types of volatile components, mainly consisting of aldehydes, pyrazines and esters, were detected. Three principle components were obtained by principal component analysis (PCA), allowing the different cultivars of tea seed oil to be characterised with strong correlation coefficients between factors. Both cluster discriminant analysis and PCA showed that geographical regions could influence the composition and content of tea seed oil's volatile components.     

食用植物油脂制取与精炼技术研究进展

我国近代油脂工业发展至今已超过半个多世纪,随着新一轮科技革命和产业革命的到来,食用植物油脂制取与精炼新技术研究受到广泛关注。基于低碳绿色、高效低耗以及产品个性化、营养健康化新需求的油料与油脂柔性加工和精准适度加工技术,是实现产业转方式、调结构、促发展的重要途径。作者从油料预处理技术、油脂制取技术和油脂精炼技术3个方面对当前的新技术研究进行了简要总结,分析当前存在的应用问题,并展望未来发展趋势,旨在为我国未来油脂科技发展提供一定参考。     

Methods for the analysis of melamine and related compounds in foods: a review

In recent years, two adulteration incidents concerning the addition of melamine (MEL) and related compounds to dairy products and vegetable proteins have occurred in China. These episodes prompted numerous governmental and private laboratories to develop or implement methods for the analysis of a wide variety of food products for MEL and related compounds, including cyanuric acid, ammeline, and ammelide. Methods have been developed for both screening and quantitation purposes; procedures used in the methods range from sensitive hyphenated chromatographic-mass spectrometric techniques to immunoselective assays. Various issues are encountered during the analysis of MEL and related compounds in food products. These issues include contamination, matrix effects, and analyte instability, and their severity varies according to the method used, and matrices and analytes examined.     

Volatile metabolites in various cereal grains

To date, studies on volatile metabolites in cereal grain have focused mainly on a single species. In this paper, results are presented of the analysis of volatile compounds in five cereal grain species (spring wheat, durum wheat, triticale, rye, oats and barley) based on representative sampling of at least 15 cultivars of individual species. Profiles of volatile compounds were determined using solid phase microextraction (SPME) and GC–TOF (time of flight mass spectrometry). Many of the volatile compounds were only present in single samples; however, several dozen were found in over 50% of samples and 46 volatiles were found in all samples. Among them there were six alcohols, 10 aldehydes and ketones, six terpenes, seven hydrocarbons and 11 benzene derivatives. The highest concentrations of these compounds were found in durum wheat, while the lowest were observed in triticale and rye.