食品中酚类内分泌干扰物的研究进展

壬基酚、辛基酚和双酚A等以其相似的结构特征和类雌激素效应被称为酚类内分泌干扰物,它们在食品包装材料及食品中的残留已引起了人们的广泛关注。本文以食品中的酚类内分泌干扰物为重点,对壬基酚、辛基酚和双酚A的性质、应用、毒性以及在食品中的污染水平、主要来源和分析测定方法等进行了评述,为我国开展食品领域内酚类内分泌干扰物的限量制定和研究提供参考。      

酚类改性氰酸酯树脂体系介电性研究

采用DSC和红外等方法研究了酚对氰酸酯树脂固化反应的影响,以及不同酚含量的氰酸酯树脂体系及其复合材料在常温、高温、宽频(7~18 GHz)等条件下介电常数及介电损耗。结果表明,酚的加入可以显著促进氰酸酯树脂的固化反应;适量酚的加入能显著提高氰酸酯树脂体系的介电性但是会降低其玻璃化转变温度;含有壬基酚的氰酸酯树脂体系复合材料在宽频下表现出稳定的介电性。     

塑料食品包装材料中壬基酚的风险评估

壬基酚是目前最受关注的环境激素之一,由于其常被用作塑料增塑剂,因此有可能残留于塑料食品包装材料中,对消费者健康造成影响。基于风险评估的基本步骤,对壬基酚的毒理学性质进行了综述,并结合从市场上采集的30种食品包装材料中壬基酚迁移量的检测结果,对目前我国塑料食品包装材料中壬基酚对消费者的健康影响进行了风险评估,结果发现,存在一定的风险,需要采取相应的风险控制措施。     

建议皮革工业禁用烷基酚聚氧乙烯醚

烷基酚聚氧乙烯醚（APE）是城市污水的主要污染物之一，在APE的自然降解过程中会产生壬基酚（NP）、短链乙氧基化物和相应的氧化物，如壬基酚乙二醇单醚（NPIE）、壬基酚二乙二醇单醚（NP2E）、壬基酚氧基乙酸（NP2EC）和壬基酚氧基乙氧基乙酸（NP2EC）等。这些产物，特别是NP、NPIE和N2PE的毒性和雌激素活性明显、生物降解性差、亲脂性强、易在污泥和生物体内积累，并可能通过食物链以慢性作用危及所有物种的生存，因此，禁用烷基酚聚氧乙烯醚是减轻环境恶化、保护生态系统的必要措施之一。     

壬基酚合成工艺的研究

以苯酚、壬烯为主要原料合成壬基酚。研究了反应温度、反应时间和催化剂用量等因素对合成反应的影响。结果表明,合成壬基酚的最佳工艺条件为:在常压下,苯酚与壬烯的物料比为1:1.7(摩尔比),反应温度为110℃,反应时间为10小时,催化剂的用量为15%(以苯酚质量份计)。     

壬基酚聚氧乙烯醚双子表面活性剂的合成

以壬基酚、多聚甲醛和环氧乙烷为原料,经3步反应合成了壬基酚聚氧乙烯醚双子表面活性剂(GNP-10),对比了不同固体超强酸催化剂对第二步反应的催化性能。考察了反应条件对2-羟甲基-4-壬基苯酚(化合物Ⅰ)和二-(2-羟基-5-壬基苯基)-甲烷(化合物Ⅱ)的转化率和收率的影响,并对化合物Ⅰ、化合物Ⅱ及 GNP-10的结构进行了表征。实验结果表明,合成GNP-10的适宜条件为:第一步,以氢氧化钠为催化剂、n(壬基酚):n(多聚甲醛)=1:1、反应温度40℃、反应时间12 h、pH 为9,此时壬基酚的转化率为63.1%,化合物Ⅰ的收率为40.2%;第二步,以 SO_4~(2-)/TiO_2固体超强酸为催化剂、n(化合物Ⅰ):n(壬基酚)=1:1、反应温度110℃、反应时间6 h,此时化合物Ⅰ的转化率和化合物Ⅱ的收率分别为73.7%和69.8%;第三步,n(化合物Ⅱ):n(环氧乙烷)=1:20,120～150℃,氢氧化钠催化下反应2 h,GNP-10的收率为98.0%。3步反应的总收率为27.5%。     

环保型丁腈橡胶NBR 3305 E的开发与生产

介绍了丁腈橡胶(NBR)环保化的发展趋势及市场需求。通过对不含壬基酚的新型抗氧剂从硫化时间、硫化胶的物理机械性能及热空气老化性能等方面进行的对比评价,综合考虑性能、外观、成本及替代方案等因素,选择以含酚和硫醚的双官能团抗氧剂在50 kt/a装置上试生产了环保型NBR 3305 E,产品质量达到了优级品标准,产品和加工性能均与NBR 3305相当。用户在使用过程中未发现明显差异,生产配方基本不做调整,制品均可以满足环保要求。     

The Bioconcentration and Degradation of Nonylphenol and Nonylphenol Polyethoxylates by Chlorella vulgaris

Nonylphenol polyethoxylates (NPnEOs), a major class of nonionic surfactants, can easily enter into aquatic environments through various pathways due to their wide applications, which leads to the extensive existence of their relative stable metabolites, namely nonylphenol (NP) and mono- to tri-ethoxylates. This study investigated the bioconcentration and degradation of NP and NPnEO oligomers (n = 1–12) by a green algae, Chlorella vulgaris. Experimental results showed that C. vulgaris can remove NP from water phase efficiently, and bioconcentration and degradation accounted for approximately half of its loss, respectively, with a 48 h BCF (bioconcentration factor) of 2.42 × 10³. Moreover, C. vulgaris could concentrate and degrade NPnEOs, distribution profiles of the series homologues of the NPnEOs in algae and water phase were quite different from the initial homologue profile. The 48 h BCF of the NPnEO homologues increased with the length of the EO chain. Degradation extent of total NPnEOs by C. vulgaris was 95.7%, and only 1.1% remained in water phase, and the other 3.2% remained in the algal cells. The algae removed the NPnEOs mainly through degradation. Due to rapid degradation, concentrations of the long chain NPnEO homologous in both water (n ≥ 2) and the algal phase (n ≥ 5) was quite low at the end of a 48 h experiment.     

Migration of plasticizersphthalates,bisphenol A and alkylphenols from plastic containers and evaluation of risk

This study investigates the potential migration of plasticisers, plastic components and additives from several plastic water bottles. Compounds studied were phthalates (dimethyl phthalate, di-n-butyl phthalate, benzylbutyl phthalate, bis(2-ethylhexyl) phthalate), bis(2-ethylhexyl) adipate, octylphenol, 4-nonylphenol and bisphenol A. Polycarbonate (PC), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene terephthalate (PET) and polystyrene (PS) plastics used in the water bottling sector were tested using three kinds of total or specific migration tests: (1) standard method UNE-EN ISO 177; (2) ultrasonic forced extraction; and (3) standard method UNE-EN 13130 UNE-EN 13130. 2005. Materials and articles in contact with foodstuffs – plastics substances subject to limitation. Part 1: guide to test methods for the specific migration of substances from plastics to foods and food stimulants and the determination of substances in plastics and the selection of conditions of exposure to food simulants.  [Google Scholar]-1. In addition, bottled waters contained in different plastic materials were analysed to determine the potential migration of target compounds in real conditions. In all cases, samples were solid-phase extracted using Oasis HLB 200?mg cartridges and analysed using GC-MS in scan-acquisition mode. Bisphenol A and 4-nonylphenol were detected in incubated samples, indicating that migration from food plastics can occur at the experimental conditions tested. The total daily intake was calculated according to the levels detected in bottled water and the assessment of the consumers’ risk was evaluated taking into consideration toxicological and legislative values.