微波消解/电感耦合等离子体质谱法同时测定食品纸包装材料与食品模拟物中24种元素

建立了微波消解/电感耦合等离子体质谱(ICP-MS)同时检测食品纸包装材料及3种食品模拟物(纯水、4%乙酸、10%乙醇)中Li,Be,B,Al,V,Cu,Mn,Zn,Cr,Ni,As,Sr,Zr,Se,Mo,Ag,Cd,Sn,Sb,Te,Ba,Hg,Tl,Pb 24种元素的分析方法,并对元素的迁移行为进行了研究。包装材料样品经微波消解后利用ICP-MS检测;迁移试验中的食品模拟物直接利用ICP-MS检测。在优化实验条件下,24种元素在0~1 000μg/L范围内线性关系良好;方法检出限(MLOD)为0.000 3~0.465 mg/kg;在1.0~1 000 mg/kg加标水平下的平均回收率为90.5%~125.3%;相对标准偏差(RSD,n=3)为1.2%~6.8%。该方法前处理简便、灵敏准确、适用范围广,可用于食品纸包装材料中元素含量的测定及迁移行为的研究,从而为食品纸包装材料的质量监督提供了科学依据。     

Epoxidized soy bean oil migrating from the gaskets of lids into food packed in glass jars. Analysis by on-line liquid chromatography-gas chromatography

The migration of epoxidized soy bean oil (ESBO) from the gasket in the lids of glass jars into foods, particularly those rich in edible oil, often far exceeds the legal limit (60 mg/kg). ESBO was determined through a methyl ester isomer of diepoxy linoleic acid. Transesterification occurred directly in the homogenized food. From the extracted methyl esters, the diepoxy components were isolated by normal-phase LC and transferred on-line to gas chromatography with flame ionization detection using the on-column interface in the concurrent solvent evaporation mode. The method involves verification elements to ensure the reliability of the results for every sample analyzed. The detection limit is 2-5 mg/kg, depending on the food. Uncertainty of the procedure is below 10%.     

蒙药匝迪-5中有害金属元素的初级形态研究

采用ICP-ASE法对匝迪-5中的Cu,As,Cd,Hg和Pb元素进行了初级形态分析。结果显示Pb和Cu在头煎液和二煎液中的含量之和分别为0.25mg/kg和0.53mg/kg。As,Cd和Hg未检出;人工胃液中Pb的含量为0.02mg/kg,Cu的含量为0.37mg/kg。说明匝迪-5煎煮液和人工胃液中重金属均低于国家药典标准的要求。     

Simultaneous determination of 11 fluorescent whitening agents in food‐contact paper and board by ion‐pairing high‐performance liquid chromatography with fluorescence detection

4,4′‐Diaminostilbene‐2,2′‐disulfonic acid based fluorescent whitening agents (DSD‐FWAs) are prohibited in food‐contact paper and board in many countries. In this work, a reliable high‐performance liquid chromatography method was developed for the simultaneous determination of 11 common DSD‐FWAs in paper material. Sample preparation and extraction as well as chromatographic separation of multicomponent DSD‐FWAs were successfully optimized. DSD‐FWAs in prepared samples were ultrasonically extracted with acetonitrile/water/triethylamine (40:60:1, v/v/v), separated on the C₁₈ column with the mobile phase containing tetrabutylammonium bromide, and then detected by a fluorescence detector. The limits of detection were 0.12–0.24 mg/kg, and the calibration curves showed the linear correlation (R² ≥ 0.9994) within the range of 8.0–100 ng/mL, which was equivalent to the range of 0.80–10 mg/kg in the sample. The average recoveries and the RSDs were 81–106% and 2–9% at two fortification levels (1.0 and 5.0 mg/kg) in paper bowls, respectively. The successful determination of 11 DSD‐FWAs in food‐contact paper and board obtained from local markets indicated that the newly developed method was rapid, accurate, and highly selective.     

UPLC–MS as a powerful technique for screening the nonvolatile contaminants in recycled PET

The possibility of using recycled polyethylene terephthalate as a food contact material is being seriously considered, but the potential migration of nonvolatile compounds from it must be assessed to ensure that it is safe to do so. In the study presented here, four samples of recycled PET were each exposed to three food simulants under the harsh extraction conditions stipulated by European legislation regarding migration tests. The nonvolatile compounds that migrated from them were determined by ultra performance liquid chromatography–mass spectrometry using three different cone voltages, and both positive and negative ionization modes. A total of 36 chemical compounds were detected, some of which were identified, including common additives such as N,N′-di-beta-naphthyl-p-phenylenediamine (antioxidant) and 2,4-di-tert-butyl-6-(5-chloro-2H-benzotriazol-2-yl)phenol (light stabilizer) as well as degradation compounds such as ethylene terephthalate dimers and trimers. In addition, specific migration values of three common components of polyethylene terephthalate (diethylene glycol, terephthalic acid, and isophthalic acid) were determined and found to occur at levels of <1 mg/kg—much lower than the specific migration limits stipulated by European legislation.     

Determination of partition behavior of organic surrogates between paperboard packaging materials and air

The suitability of recycled paperboard packaging materials for direct food contact applications is a major area of investigation. Chemical contaminants (surrogates) partitioning between recycled paper packaging and foods may affect the safety and health of the consumer. The partition behavior of all possible organic compounds between cardboards and individual foodstuffs is difficult and too time consuming for being fully investigated. Therefore it may be more efficient to determine these partition coefficients indirectly through experimental determination of the partitioning behavior between cardboard samples and air. In this work, the behavior of organic pollutants present in a set of two paper and board samples intended to be in contact with foods was studied. Adsorption isotherms have been plotted and partition coefficients between paper and air have been calculated as a basis for the estimation of their migration potential into food. Values of partition coefficients (Kpaper/air) from 47 to 1207 were obtained at different temperatures. For the less volatile surrogates such as dibutyl phthalate and methyl stearate higher Kpaper/air values were obtained. The adsorption curves showed that the more volatile substances are partitioning mainly in air phase and increasing the temperature from 70 to 100 degrees C their concentrations in air (Cair) have almost doubled. The analysis of surrogates was performed with a method based on solvent extraction and gas chromatographic-flame ionization detection (GC-FID) quantification.     

气相色谱-质谱法检测食品中的丙烯酰胺

建立了一种用于食品中丙烯酰胺含量的气相色谱-质谱联用检测方法。通过水和甲醇提取食品中的丙烯酰胺,经蛋白变性净化后用溴水对其进行加成衍生化,再采用有机溶剂进行液液萃取,之后同三乙胺发生定量反应转化为性质更稳定的产物后由气相色谱-质谱联用仪检测,同位素内标法定量。该方法在0.02,0.05和0.2 mg/kg等3个添加水平下面粉和面包中丙烯酰胺的回收率处于80%和110%之间,相对标准偏差（RSD）不大于12.7%;在0.04～4.00 mg/L内呈现良好的线性关系;灵敏度高,最低检测限达到5 μg/kg;选择性好,能有效消除复杂基质带来的干扰。可作为常见样品中丙烯酰胺含量检测的确证方法。     

Occurrence of 2-phenylphenol in food paper packages

Twenty three paper based packaging materials commercially used for food packaging in the Czech Republic were analysed with regard to 2-phenylphenol (OPP) content using HPLC technique with fluorimetric detection. The HPLC method was modified with the aim to increase its sensitivity. OPP was detected in quantities ranging from 10 mg kg^?1 to 527 mg kg^?1 in twenty tested samples. The level of OPP in packaging materials was in close correlation to the content of recycled pulp in used paper material. The migration of OPP from two packaging materials comprised of paperboard coated with low density polyethylene (LDPE) into food simulants was determined at 40°C for 10 days. The levels of migration into 3% acetic acid, 10% ethanol and olive oil were below the limit of detection of used analytical procedure. In the case of 95% ethanol, 13% and 21% of OPP present in tested samples were transferred into simulant. The found occurrence of OPP in paper packages does not pose any significant safety risk for food consumer, but OPP could be considered as wide spread contaminant in paper materials.      

气相色谱-质谱法测定聚氯乙烯包装材料和食品模拟物中的46种增塑剂

建立了46种增塑剂在聚氯乙烯(PVC)食品包装材料中的含量及其在水、3%乙酸、10%乙醇和橄榄油4种食品模拟物中迁移量的气相色谱-质谱(GC-MS)测定方法。食品包装材料、水质模拟物和橄榄油中增塑剂分别采用溶解-沉淀法、正己烷液-液萃取和凝胶渗透色谱(GPC)法提取。采用GC-MS法,在选择离子监测模式(SIM)下对46种增塑剂进行定性,采用外标法进行定量测定。各种增塑剂在0.1～2.0 mg/L质量浓度范围内呈线性,相关系数为0.9910～0.9999,各组分检出限均在0.005～0.05 mg/kg之间。在2种食品模拟物中,3个浓度添加水平下46种增塑剂的加标回收率在69.51%～107.21%之间,精密度(RSD, n=6)为3.53%～18.95%。该方法可满足PVC食品接触制品及4种不同性质的食品模拟物中多种类增塑剂的快速筛查和准确定性、定量测定要求。     

高效液相色谱-紫外检测法同时测定食品接触材料中7种苯多酸及其衍生物的特定总迁移量

建立了高效液相色谱-紫外检测(HPLC-UV)同时测定5种食品模拟物(10%(v/v)乙醇、20%(v/v)乙醇、50%(v/v)乙醇、3%(w/v)乙酸和橄榄油)中偏苯三甲酸、偏苯三甲酸酐、间苯二甲酰氯、间苯二甲酸、对苯二甲酰氯、邻苯二甲酸、对苯二甲酸的特定总迁移量(SML(T))的方法。用食品模拟物浸泡待测样品,冷却至室温并混匀,水基食品模拟物经亲水性聚四氟乙酸针头过滤器过滤后进样;橄榄油用0.1%(w/v)乙酸铵水溶液提取后,下层清液用亲水性聚四氟乙烯针头过滤器过滤后进样。用Synergi Polar-RP色谱柱(250 mm×4.6 mm, 4 μm)分离,梯度洗脱,检测波长为232 nm。5种食品模拟物中的定量限为0.1~0.2 mg/kg;水基食品模拟物在0.5~12 mg/L、橄榄油食品模拟物在0.5~12 mg/kg范围内线性关系良好(r² > 0.99991); 1.25、2.5、6.25 mg/kg水平的加标回收率为94.3%~105%,相对标准偏差为0.1%~2.3%。结果表明,该方法的色谱分离和线性关系较好,回收率和准确度高,完全满足欧盟(EU)No 10/2011法规附表2中7种苯多酸及其衍生物的SML(T)的限量要求,并已应用于实际样品的检测。     

Determination of the migration of 8 benzophenones in food contact materials and products by HPLC-MS / MSEI北大核心CSCD

建立了高效液相色谱-串联质谱法测定食品接触材料及制品中8种二苯甲酮类物质迁移量的方法。样品经过食品模拟物浸泡后，水、4%乙酸、10%乙醇、20%乙醇、50%乙醇模拟物直接进样，95%乙醇模拟物用水按照1:4比例稀释后进样，橄榄油和异辛烷模拟物用甲醇-水混合溶液萃取后进样。采用C₁₈柱分离，用甲醇-0.1%甲酸水溶液为流动相梯度洗脱，质谱采用正离子多反应监测（MRM）模式运行。本方法在8种食品模拟物中的定量限为0.01～0.20 mg/kg;在0.04～0.80 mg/kg, 0.2～2.0 mg/kg, 0.6～3.0 mg/kg线性范围内相关系数良好（R≥0.9958）;加标实验结果显示相对标准偏差（RSD）为0.61%～7.8%。该方法可用于食品接触材料及制品中二苯甲酮类物质迁移量的测定。     

电感耦合等离子体质谱法测定苎麻不同部位的铬、砷、镉、铅4种重金属元素含量

采用硝酸-双氧水-氢氟酸体系对苎麻不同部位样品进行微波消解,通过智能控温加热器赶酸,利用电感耦合等离子体质谱(ICP-MS)检测苎麻不同部位的铬、砷、镉及铅含量.结果表明:方法操作简便,分析速度快,灵敏度及线性较好,各元素的检出限为~(52)Cr 0.05 mg/kg、~(75)As 0.02 mg/kg、~(111)Cd 0.02 mg/kg、~(208)Pb 0.03 mg/kg,线性范围分别为Cr 0.5~50 mg/kg、As和Cd均为0.1~12.5 mg/kg、Pb 0.2~25 mg/kg.方法精密度和稳定性较好,试验回收率在80.0%~125%之间.初步判断苎麻不同部位4种重金属元素的高低水平,以及苎麻对土壤中的重金属有一定吸附作用.     

Analysis of 16 phthalic acid esters in food simulants from plastic food contact materials by LC‐ESI‐MS/MS

An RP LC‐ESI‐MS/MS method for the determination of the migration of 16 primary phthalic acid esters from plastic samples has been developed using distilled water, 3% acetic acid, 10% alcohol, and olive oil as food simulants. Detection limits were 1.6–18.5 μg/kg in distilled water, 1.4–17.3 μg/kg in 3% acetic acid, 1.4–19.2 μg/kg in 10% alcohol, and 31.9–390.8 μg/kg in olive oil. The RSDs were in the range of 0.07–11.28%. The real plastic products inspection showed that only few analyzed samples were phthalates contaminated. Bis‐2‐ethylhexyl ester and dibutyl phthalate were the common items migrated from the plastic products into food and feeds, but the migration concentrations were far below the limits set by European Union (1.5 mg/kg for bis‐2‐ethylhexyl ester and 0.3 mg/kg for dibutyl phthalate).     

PVC塑料包装中化学物总迁移的研究

食品包装安全是食品安全的一个重要环节.食品容器、包装等接触材料与食品长期接触会发生"迁移",分为总迁移(overall migration)和特定迁移(specific migration)[1].其中,特定迁移是指某一特定物质在食品包装或容器与食品接触过程中发生的迁移;总迁移是从塑料材料或制品样品到试验媒介的组分总体迁移量.就物质而言,有可知物与未知物,就过程而言,有包装向食品的迁移,也有食品向包装的渗透、吸收等.进行总迁移实验有助于更全面了解一种材料与食品接触会发生的总体变化,对特定迁移的研究起有辅助与补充作用.欧盟对于食品模拟物、样品及前处理[2]、迁移测试方法[3]都有相应规定[4],本实验采用整体浸泡法,研究了PVC材料中化学物在不同食品模拟物中的总迁移.1 实验部分1.1 实验试剂和器材     

成都市农业土壤重金属污染特征初步研究

对成都市农业土壤中七种重金属元素Pb、Hg、Cr、As、Cu、Zn和Cd进行了测定和研究,并进行了潜在生态风险评价。结果表明,成都市农业土壤重金属元素含量分别为:Pb 77.27mg/kg,Hg 0.31 mg/kg,Cr 59.50 mg/kg,As 11.27 mg/kg,Cu 42.52 mg/kg,Zn 227.00 mg/kg,Cd0.36 mg/kg;重金属潜在的生态危害因子表明,Hg和Cd达到中等生态危害程度,Pb、As、Cu、Zn、Cr达到轻微生态危害;多种重金属的生态系统的潜在生态风险指数(RI)表明,成都市农业土壤生态危害级别为中等生态危害。     

气相色谱-质谱法测定油炸淀粉类食品中的丙烯酰胺

 建立了油炸淀粉类食品中丙烯酰胺的溴衍生化气相色谱-质谱(GC-MS)测定方法。样品经水提取、高速离心、石墨化 炭黑柱净化、溴衍生化后,以GC-MS选择离子进行定性,同位素稀释技术定量。该方法的检出限为5 μg/kg,回收率为90％ ～105％,相对标准偏差为6.3％。利用该方法对市场上某些油炸淀粉类食品进行了初步测定,发现薯片和炸薯条中含有27 8~4518 μg/kg的丙烯酰胺。     

Development of methods for testing barriers in food packaging materials

In some countries recycled materials are not allowed to come into contact with food without a protective layer such as plastic or virgin fiber. The purpose of this kind of barrier is to reduce migration of substances form beyond the barrier to the food. Two methods for studying a functional barrier are described. Both utilize migration cells in which one surface of the test specimen (for example a paper plate) is exposed to the food simulant. The first method involves the addition of indidcatsor substances to the non-food contact layer. The second method is to measure the migration of substances originally present in the layers beyond the functional barrier layer. Several kinds of barrier used in commercial papaer plates were studied and differences between them were found.     

ICP-OES法测成都市三环内表层土壤13种金属元素含量

采用电感耦合等离子体发射光谱(ICP-OES)法同时测定成都市三环内表层土壤13种金属元素含量与分布.研究显示,重金属元素As、Cr、Cu、Ni、Pb、Zn平均含量分别为24.3mg/kg,154.0 mg/kg,32.8 mg/kg,31.4 mg/kg,64.9 mg/kg,165.1 mg/kg.Mn、Mo、Fe平均含量分别为400.1 mg/kg,10.7 mg/kg,18911 mg/kg.Sr 74.0 mg/kg、Sb 4.9 mg/kg、Co 13.7 mg/kg、Sc 5.9 mg/kg.采用单项污染指数法和内梅罗综合污染指数法来评价土壤重金属污染程度,并针对表层土壤金属污染状况进行了讨论.     

Analytical protocol to study the food safety of (multiple-)recycled high-density polyethylene (HDPE) and polypropylene (PP) crates: Influence of recycling on the migration and formation of degradation products

An analytical protocol was set up and successfully applied to study the food safety of recycled HDPE and PP crates. A worst-case scenario was applied that focused not only on overall migration and specific migration of accepted starting materials but also on migratable degradation products of polymers and additives that may be formed during mechanical recycling.The analytical protocol was set up to cover a wide variety of possible migrants. Identification and semi-quantification were possible for almost all migrants that increased significantly with increasing mechanical recycling steps for both the HDPE and PP crates.It was concluded that the analytical protocol was suitable to study the influence of (multiple) recycling on the food safety of plastic materials. The protocol can be applied to other plastic food contact materials and provides valuable information on the food safety of the recycling process and the resulting recycled food contact materials in addition to challenge testing.