聚氯乙烯塑料中多种邻苯二甲酸酯类增塑剂的同时测定

为了在线监控聚氯乙烯塑料中增塑剂的含量,利用傅立叶变换红外光谱法-ATR技术测定样品的红外光谱,采用偏最小二乘法对所测红外光谱进行分析,建立了一种无损快速分析方法,定量地测定聚氯乙烯塑料中多种邻苯二甲酸酯类增塑剂的含量。该方法测量精密度的变异系数小于6%,测量准确度的变异系数小于3%。该方法不受基体的干扰,简单快速,适合于流水线的质量控制。     

Heterogeneous oxidation of indoor surfaces by gas‐phase hydroxyl radicals

We investigate heterogeneous oxidation kinetics of monolayer‐thick, surface‐sorbed organics, namely di‐n‐octyl phthalate (DnOP) and palmitic acid (PA), with gas‐phase OH. The pseudo‐first order rate constants for organic loss at OH concentrations of 1.6 × 10⁸ molecules/cm³ are: (2.3 ± 0.1) × 10^?4 to (4.8 ± 0.8) × 10^?4 s^?1, and (1.3 ± 0.5) × 10^?4 s^?1 for DnOP and PA, respectively. Films developed in indoor office environments over a few weeks are also oxidized using the same OH concentration. Heterogeneous decay rate constants of mass signals from these films, attributed to phthalates (MW = 390.6) and to PA, are similar to those for the single‐component films, ie, (1.9 ± 0.4) × 10^?4 to (3.4 ± 0.5) × 10^?4 s^?1, and (1.1 ± 0.4) × 10^?4 s^?1, respectively. These results suggest that the lifetimes for OH heterogeneous oxidation of monolayer‐thick indoor organic films will be on the timescale of weeks to months. To support this argument, we present the first analysis of the mass transfer processes that occur when short‐lived gas‐phase molecules, such as OH, are taken up by reactive indoor surfaces. Due to rapid chemical production, the diffusion limitation to mass transfer is less important for short‐lived molecules than for molecules with little chemical production, such as ozone.     

A general mechanistic model for predicting the fate and transport of phthalates in indoor environments

A mechanistic model that considers particle dynamics and their effects on surface emissions and sorptions was developed to predict the fate and transport of phthalates in indoor environments. A controlled case study was conducted in a test house to evaluate the model. The model‐predicted evolving concentrations of benzyl butyl phthalate in indoor air and settled dust and on interior surfaces are in good agreement with measurements. Sensitivity analysis was performed to quantify the effects of parameter uncertainties on model predictions. The model was then applied to a typical residential environment to investigate the fate of di‐2‐ethylhexyl phthalate (DEHP) and the factors that affect its transport. The predicted steady‐state DEHP concentrations were 0.14 μg/m³ in indoor air and ranged from 80 to 46 000 μg/g in settled dust on various surfaces, which are generally consistent with the measurements of previous studies in homes in different countries. An increase in the mass concentration of indoor particles may significantly enhance DEHP emission and its concentrations in air and on surfaces, whereas increasing ventilation has only a limited effect in reducing DEHP in indoor air. The influence of cleaning activities on reducing DEHP concentration in indoor air and on interior surfaces was quantified, and the results showed that DEHP exposure can be reduced by frequent and effective cleaning activities and the removal of existing sources, though it may take a relatively long period of time for the levels to drop significantly. Finally, the model was adjusted to identify the relative contributions of gaseous sorption and particulate‐bound deposition to the overall uptake of semi‐volatile organic compounds (SVOCs) by indoor surfaces as functions of time and the octanol‐air partition coefficient (K_oa) of the chemical. Overall, the model clarifies the mechanisms that govern the emission of phthalates and the subsequent interactions among air, suspended particles, settled dust, and interior surfaces. This model can be easily extended to incorporate additional indoor source materials/products, sorption surfaces, particle sources, and room spaces. It can also be modified to predict the fate and transport of other SVOCs, such as phthalate‐alternative plasticizers, flame retardants, and biocides, and serves to improve our understanding of human exposure to SVOCs in indoor environments.     

儿童用品中邻苯二甲酸盐的检测

文章采用超声震荡萃取—气相色谱法建立测定儿童用品中邻苯二甲酸酯的方法;以正己烷为萃取溶剂,然后采用气相色谱法—氢火焰离子检测器,进行检测分析,该方法的平均回收率为69.0%~103.2%,相对平均偏差为1.8%~5.9%。该方法用于儿童用品样品中14种邻苯二甲酸酯的测定,具有较好的准确性。     

塑料食品包装中邻苯二甲酸酯类塑化剂含量调查

目的 了解塑料食品包装中18种邻苯二甲酸酯的含量现状.方法 选取280批不同材质的塑料食品包装,依据GB/T 21928-2008《食品塑料包装材料中邻苯二甲酸酯的测定》采用气相色谱-质谱法进行检测.以正已烷为提取溶剂,超声波提取,采用HP-5MS石英毛细管柱(30 m×0.25 mm,0.25 μm)色谱柱程序升温分离,以保留时间和特征离子为定性依据,外标法定量.结果 62批聚氯乙烯材质的食品包装中18种邻苯二甲酸酯含量95％小于法规限量,82批复合材质和136批其它材质的食品包装中18种邻苯二甲酸酯含量100％小于法规限量,检出最多的是邻苯二甲酸二(2-乙基)己酯,3批聚氯乙烯材质的食品包装中邻苯二甲酸二(2-乙基)己酯严重超标.结论 塑料食品包装中邻苯二甲酸酯暴露水平较低,聚氯乙烯材质存在的潜在危害较大,应引起重视,加强监管.     

食品中邻苯二甲酸酯类增塑剂含量的测定

采用气相色谱法测定14种食品中5种邻苯二甲酸酯[邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸二乙酯(DBP)、邻苯二甲酸二(2-乙基己基)酯(DEHP)、邻苯二甲酸二正辛酯(DnOP)]的含量.样品经正己烷溶解、超声波辅助提取、固相萃取浓缩富集等预处理,以保留时间定性,外标法定量.结果表明,该分析条件下样品的回收率为72.3%～101.5%,相对标准偏差为2.69%～5.84%,说明本方法准确可靠.14种食品中检出的邻苯二甲酸酯类约69%的含量高于欧洲规定的每天0.3 mg/kg体重的标准,表明邻苯二甲酸酯类污染物在被检食品中有较大的的迁移.     

基于斑马鱼幼鱼的塑化剂肝毒性危害识别研究

目的 采用塑化剂邻苯二甲酸二乙基己酯（DEHP）和邻苯二甲酸二丁酯（DBP）作为阳性对照,建立斑马鱼幼鱼脂肪肝毒性风险评估模型进行塑化剂邻苯二甲酸丁酯苯甲酯（BBP）肝毒性危害识别。方法 分析DEHP和DBP暴露后斑马鱼肝脏脂肪信号强度及过氧化物酶体增殖物激活受体（PPAR）靶基因CD36的表达,初步构建斑马鱼幼鱼肝毒性模型;基于此模型对BBP进行肝毒性评价,此外采用肝脏表达绿色荧光转基因斑马鱼幼鱼进行肝密度分析、甘油三酯（TG）定量检测以及成鱼肝脏病理检查进一步验证模型的可靠性,应用基准剂量法（BMD）推导关键效应点。结果 DEHP、DBP表现出极显著诱发脂肪肝风险（均P<0.01）,显著上调CD36相对表达量（P<0.001,P<0.05）,提示造模成功。BBP（0.000 012 5%、0.000 025%、0.000 05%）诱发斑马鱼幼鱼显著的脂质沉积（P<0.05,P<0.001,P<0.001）、显著影响密度（P<0.05,P<0.01,P<0.01）、显著增加TG蓄积（P<0.05,P<0.05,P<0.01）、上调CD36基因表达。此外,BBP（≥0.000 012 5%）诱发斑马鱼成鱼肝脏部位脂质空泡形成、空泡间隙和数量减少,提示BBP具有明显的肝毒性。关键效应为肝脏脂肪信号强度（S）,基准剂量下限（BMDL）值为0.013 mg/L。结论 本研究成功构建了一种通过肝脏脂肪信号强度来识别塑化剂肝毒性的斑马鱼幼鱼模型,结合基准剂量法进一步为塑化剂肝毒性危害识别提供科学依据。     

乳制品中邻苯二甲酸酯类化合物残留量检测方法

建立了测定乳制品中邻苯二甲酸之类物质残留量的气质联用方法。液体乳及含乳饮料采用正己烷萃取后直接测定;乳粉类样品先用正己烷萃取、再用凝胶萃取小柱净化后上机测定。色谱测定条件为采用DB-5MS(30 m×0.25 mm×0.25μm)石英毛细管柱梯度升温进行分离质谱条件为色谱与质谱接口温度280℃、电子轰击源、选择离子扫描模式、电力能量70 eV。通过各组分的定性与定量离子分别对邻苯二甲酸酯进行定性、定量测定。该方法样品加标回收率分别在86%~105%之间,液体乳及乳饮料检出限为0.05 mg/kg,乳粉为0.1 mg/kg。本法具有操作简单、测定快速、灵敏度高、专属性及准确性好等优点。     

室内空气中酞酸酯类物质分析的研究

以固相微萃取（SPME）方法为前处理和分离手段采集室内空气中的酞酸酯类物质，进而在GC／MS上对其进行分析测定。通过对SPME中使用的极性与非极性纤维萃取头的萃取效果进行对比．确立了该类室内空气中酞酸酯类物质的分离和分析方法．并且比较了不同环境中室内各种邻苯二甲酸酯类的相对浓度大小。实验发现．与用传统的有机溶剂吸收空气中的化合物的方法相比．该方法可以检测出低浓度邻苯二甲酸二（2-乙基己基）酯（DEHP）．并且简化了实验过程．减少了干扰及有机溶液的使用量．并可以测定出浓度较低的酞酸酯类物质。     

Oestrogenicity of paper and cardboard extracts used as food containers

Bisphenol-A (BPA), dibutyl phthalate (DBP), and di-2-ethylhexyl phthalate (DEHP), which are common chemical residues in food-packaging materials, were investigated in paper and cardboard containers used for take-away food. The oestrogenicity of aqueous extracts was tested in E-Screen bioassay and analysis carried out by high-performance liquid chromatography (HPLC) and gas chromatography-mass spectrometry (GC/MS). Oestrogenicity was demonstrated in 90% of extracts (geometric mean [GM] = 11.97 pM oestradiol equivalents g^-1). DEHP, DBP, and BPA (GM = 341.74, 37.59, and 2.38 ng g^-1 of material) were present in 77.50, 67.50, and 47.50% of samples, respectively. In bivariate analyses, no significant association was found between the levels of these chemicals and oestrogenicity in cardboard/paper extracts. A close-to-significant association was found between oestrogenicity and DBP (β = 1.25; p = 0.06) in paper extracts, which reached statistical significance in multivariate analysis (β = 1.61; p = 0.03). Paper and cardboard used in food packaging may contribute to the inadvertent exposure of consumers to endocrine-disrupting chemicals.