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.     

Migration of bisphenol A into water from polycarbonate baby bottles during microwave heating

A comprehensive migration database was established for bisphenol A from polycarbonate baby bottles into water during exposure to microwave heating. Eighteen different brands of polycarbonate baby bottles sold in Europe were collected. Initial residual content of bisphenol A and migration after microwave heating were determined. Residual content of bisphenol A in the polycarbonate baby bottles ranged from 1.4 to 35.3 mg kg^?1. Migration of bisphenol A was determined by placing a polycarbonate bottle filled with water in a microwave oven and heating to 100°C; the level of bisphenol A in the water was analysed by GC–MS. The procedure of microwave heating and analysis was repeated twice for the same bottle and, thus, three migration extracts were prepared for each test specimen. Migration of bisphenol A into water ranged from <0.1 to 0.7 µg l^?1. There was no correlation between the amount of residual content of bisphenol A in the bottles and the migration of bisphenol A into water. Furthermore, there was no correlation between the amounts of bisphenol A in consecutive migration extracts. Data show that during three microwave-heating cycles of a baby bottle made from polycarbonate, microwave radiation had no effect on the migration of bisphenol A into water from polycarbonate. All levels found were well below the specific migration limit of 0.6 mg kg^?1 specified for bisphenol A in Commission Directive 2004/19/EC.     

Migration of bisphenol A from polycarbonate baby bottles purchased in the Spanish market by liquid chromatography and fluorescence detection

During the last decade the safety of bisphenol A (BPA) monomer in polycarbonate baby bottles has drawn the attention of both the public and the scientific community. This paper presents the results of BPA migration from polycarbonate baby bottles bought in the Spanish market, into simulant B (3% acetic acid), 50% ethanol and into real food (reconstituted infant formula). Furthermore, it was also the objective of this study to assess the suitability of 50% ethanol as a simulant for infant formula. BPA was analysed by a multi-analyte liquid chromatography method with fluorescence detection and mass spectrometry confirmation. The method was in-house validated and accredited by the national accreditation body. The validation results for this analyte in the previous mentioned matrices were: LOD?=?0.004–0.007?mg?kg^–1; LOQ (validated)?=?0.03?mg?kg^–1; RSD%?=?3.4–5.8; and recovery?=?106.6–118.2%. A collection of 72 different baby bottle samples from 12 different brands were analysed. Baby bottle material was identified by FTIR. The migration test conditions used were those recommended for baby bottles in the Guidelines on testing conditions for articles in contact with foodstuffs (with a focus on kitchenware), prepared by the European network of laboratories for food-contact materials. In most of the migration assays the results were below the LOD. In four of the commercial brands there was detectable migration into the simulant 50% ethanol and BPA was detected in only two samples of infant formula (0.01?mg?kg^–1). Migration results obtained were in compliance with European Union regulations.     

Occurrence of fumonisins in Catalonia (Spain) and an exposure assessment of specific population groups

Fumonisin B₁ (FB₁) and B₂ (FB₂) are mycotoxins produced by Fusarium verticillioides and F. proliferatum and common contaminants of cereal crops. The objectives of this study were to (1) study the occurrence of fumonisins in Catalonia (north-eastern region of Spain) and (2) assess the exposure of the Catalonian population to these mycotoxins. Contamination data was provided by a wide survey where 928 individual samples were pooled to analyse 370 composite samples. Fumonisins were extracted and purified using immunoaffinity columns and determined by HPLC with fluorescence detection. The raw consumption data came from a nutritional study specifically designed to assess the dietary intake of the main foodstuffs related to fumonisin contamination for all population age groups. In addition, two specific groups were selected with respect to maize consumption: immigrants and celiac sufferers. Contamination and consumption data were combined by simulation using an essentially parametric–parametric (P-P) method. The P-P method draws sampling values from distribution functions fitted to consumption and contamination datasets. Moreover, to quantify the accuracy and reliability of the statistical estimates, we built related confidence intervals using a Pseudo-Parametric bootstrap method. The results of this study show that fumonisins are commonly found in some commodities on the Catalonian market, such as beer, corn snacks and ethnic foods; however, the values were well below the permitted maximum EU levels. The most exposed group were infants followed by immigrants but, in all cases, they were below the TDI of 2?µg/kg bw/day.     

2-Isopropylthioxanthone (2-ITX) in food and food packaging materials on the German market

To elucidate the occurrence of the photo-initiator, 2-isopropylthioxanthone (2-ITX), more than 100 food products on the German market, packed in cartons, plastic cups and foils, were investigated. For this, a rapid method to detect 2-ITX in food packaging materials was established. In case of positive findings, the accompanying foodstuffs were analysed in a subsequent step using different extraction methods, depending on the fat content of the food. Determination of the photo-initiator was done by high-performance liquid chromatography with diode array and fluorescence detection (HPLC-DAD/FLD). Recoveries ranged between 94 and 106% for non-fatty (RSD ≤ 1.1) and between 80 and 105% for fatty foods (RSD ≤ 8.5). The limit of detection and limit of quantification were determined to 2 and 5 µg l^-1. 2-ITX was detected in 36 of 137 packages (26%) and significant migration occurred in 75% of the packaging materials tested positive. The levels of 2-ITX ranged up to 357 µg kg^-1 in orange juice.     

一种自动循环淋水婴儿澡盆设计

通过分析目前在家庭中给初生婴儿使用婴儿澡盆洗澡过程中,婴儿裸露在温水面以上的部位容易受凉、澡盆中的水温也会不断降低等不足的基础上,设计出通过运用脚踏式机构、流体传动与控制系统、温度控制系统等一种自动循环淋水婴儿澡盆,从放好温水的婴儿澡盆中脚踏取水,实现自动淋水,在不增加澡盆水位的前提下,能够对婴儿露在水面外的身体取得较好的保温效果,再通过水温控制系统,能控制淋水水温在36~39℃之间,保证婴儿具有适宜的洗澡水温。自动循环淋水婴儿澡盆具有安全,经济,实用等诸多优点,有较好的市场应用前景。     

佛山市售稻米及其制品中的高氯酸盐污染特征分析

目的 了解佛山市市售稻米及其制品中的高氯酸盐污染情况,为标准制订和风险管理提供理论基础。方法 2021年3月采集佛山市5个区25个街道的农贸市场、超市、餐饮店和母婴店销售的稻米及其制品共233份,采用液相色谱串联质谱仪法检测样中高氯酸盐浓度,分析稻米及其制品中的高氯酸盐污染特征。结果 高氯酸盐在稻米样品中检出率为57.8%(52/90),湿米粉为98.8%(79/80),糯米制品为90%(18/20),特色米制品为100%(12/12),婴幼儿辅食为87.1%(27/31)。稻米样品中的高氯酸盐平均浓度为2.5μg/kg,湿米粉为6.5μg/kg,糯米制品为3.7μg/kg,特色米制品为4.3μg/kg,婴幼儿谷类辅食为5.5μg/kg。不同稻米亚种中,籼米样品中的高氯酸盐平均浓度为2.9μg/kg,粳米为0.5μg/kg,糯米为4.2μg/kg。结论 市售稻米及其制品中的高氯酸盐污染较为普遍,其中稻米的高氯酸盐污染水平低于稻米制品和婴幼儿辅食,而湿米粉是稻米制品中高氯酸盐污染水平最高的一种,婴幼儿辅食中的高氯酸盐污染水平也较高。     

共享理念下的童车可持续使用策略研究

目的基于共享理念对童车的可持续使用提出策略与应用方法。方法分析现代童车市场现状和使用人群存在的需求,以共享理念为指导,对如何将关注问题的焦点从以环境为中心,转到以可持续发展的新生活和生产方式为中心进行探讨。结论通过对童车使用的背景资料及童车产品特性的研究,以共享经济理念下的可持续设计方法为指导,提出关于童车消费模式的可持续使用策略,并基于此策略设计一款童车产品以验证其可行性。     

曲酸处理对娃娃菜采后褐变的影响

为研究曲酸处理对娃娃菜茎部切口褐变的影响及其机制,本实验用0.05?g/L曲酸和超纯水(对照)分别浸泡娃娃菜茎部切口1?min,再在20?℃、相对湿度90％的条件下贮藏5?d,每天取样分析其感官品质并测定呼吸强度、乙烯释放速率、总酚含量、类黄酮含量及褐变相关酶活力.结果表明:与对照相比,曲酸处理可以有效保持娃娃菜的感官...