食品中二恶英类化合物的污染与分析

简要介绍二恶英类化合物的化学结构特征、主要来源以及食品中二恶英类化合物对人体健康的主要危害和影响,综述食品中二恶英类化合物的主要化学分析方法和生物检测方法,最后对目前我国在食品中二恶英类化合物的安全性方面亟待解决的问题进行了展望。     

纸浆有氯漂白产生的二恶英类化合物及AOX

行业内外久已知悉,在有氯漂白中产生了“二恶英类”剧毒物质,并引起了环保、制浆工作者及政府部门的极大关注。所谓“二恶英”(ｄｉｏｘｉｎｓ)是一系列多种有机氯化物的简称,科学的称谓应当是二恶英类化合物。二恶英类化合物的构成二恶英类化合物系聚氯二苯并对位二恶英(ｐｏｌｙｃｈｌｏｒｏ-ｄｉｂｅｎｚｏ-ｐ-ｄｉｏｘｉｎｓ,ＰＣＤＤ)与聚氯二苯并呋喃(ｐｏｌｙｃｈｌｏｒｏｄｉ-ｂｅｎｚｏ-ｆｕｒａｎ,ＰＣＤＦ)两大系列化合物的统称,其分子结构式分别如下:据报道,由于分子结构中氯化数量及其所在位置的不同,共有７５种ＰＣＤＤ和１…     

再生金属冶炼中二恶英污染监测与管理的研究

冶炼再生金属的过程伴随多种污染物的产生,二恶英污染物是较为常见的污染物类型,它对环境的影响比较大,并对人体健康有较大危害。本文阐述二恶英污染物的特性和危害,分析再生金属冶炼中二恶英类污染物的监测要点,并提出防控管理的具体措施,实现对二恶英类污染物的有效控制,从而促进再生金属冶炼产业的可持续发展。     

二恶英达标排放迫在眉睫

制浆造纸行业是我国二恶英排放六大重点源之一，淘汰和削减危害人类健康和环境的二恶英是《斯德哥尔摩公约》和《国家实施计划》（NIP）的重要任务。新《制浆造纸工业水污染物排放标准》中第一次列入了二恶英排放限值，并将从2011年7月起全面实施，但二恶英达标排放面临着严重的技术瓶颈。削减二恶英，重点是控制制浆过程二恶英类污染物的发生，尽快开发快速廉价的监测新方法，加强生物和化学技术降解二恶英的研究。     

＂二恶英＂——危害人类健康的头号杀手

什么是“二恶英”,说起来吓人!“二恶英”（dioxin）属于氯化三环芳烃类化合物,是比砒霜毒900多倍的毒中之毒,具有生殖毒性、免疫毒性和内分泌毒性,是一种非常稳定又难以分解的一级致癌、致畸物质,被世界卫生、环保组织视为21世纪最危险的持久性有机污染物。科学研究表明,二恶英类有机污染物在环境中难以被自然分解,能够在水体、土壤和底泥等多介质环境中残留数年或更长时问（持久性）,     

欧盟制定食品中二恶英,二恶英样多氯联苯和非二恶英样多氯联苯残留限量的取样和分析方法

正欧盟委员会发布EU 2017/644号法规,制定食品中二恶英、二恶英类多氯联苯(PCBs)和非二恶英类多氯联苯取样和检测方法,并废除EU 589/2014条例。EU 589/2014条例由EU 2017/644号法规的附件I~IV替代,附件I列出定义和缩写,附件II规定了官方控制抽验水平,附件III规定二恶英、呋喃、二恶英类PCBs的样品制备和检测方法,附件IV规定非二恶英类PCBs的检测方法及其要求,本法规拟于官方公报发布后     

二恶英及其类似物 I 环境与食品污染

二恶英（ｄｉｏｘｉｎ）是非人为生产、没有任何用途伴随存在于各种环境介质的一类环境持续存在的污染物。因其毒性极高,世界卫生组织规定人体暂定每日允许摄入量为１～４ｐｇ／ｋｇＢＷ,由于公众对环境污染问题的广泛关注,对其研究已成为当今环境研究领域的前沿课题。１　结构与术语　二恶英从化学术语上是不准确的,实际上它指一类氯代含氧三环芳烃类化合物。属于含氧三环芳烃类化合物二苯并－对－二恶英（ｄｉｂｅｎｚｏ－ｐ－ｄｉｏｘｉｎ）和二苯并呋喃（ｄｉｂｅｎｚｏｆｕｒａｎ）,这类化合物环上的氢可以被氯取代,如２,３,７…     

食品中二恶英检测方法的研究进展

简要介绍了二恶英的种类、性质及其在食品中的残留情况,详细介绍了目前食品中二恶英残留的主要检测方法——化学检测方法、生物学检测方法、免疫检测方法,重点论述了样品的前处理过程。     

中华人民共和国卫生部通告卫通[2001]3号

根据《卫生部健康相关产品检验机构认定和管理办法》的规定 ,经审核 ,认定中国科学院水生生物研究所二恶英检测实验室为卫生部二恶英检测实验室 ,检测类别为食品、化妆品 ,二恶英检测项目见附件。特此通知。中华人民共和国卫生部二○○一年三月八日附件 :二恶英检测项目(共 2 9项 )　　　　　　　　　四氯代二苯并二恶英总量五氯代二苯并二恶英总量六氯代二苯并二恶英总量七氯代二苯并二恶英总量八氯代二苯并二恶英总量四氯代至八氯代二苯并二恶英总量2 ,3,7,8 四氯代二苯并二恶英总量1,2 ,3,7,8 五氯代二苯并二恶英总量1,2 ,3,4 ,7,8 六氯…     

二恶英及其对人类的影响

１９９９年４月,比利时发生了以肉鸡为主的二恶英（Ｄｉｏｘｉｎ,戴奥辛）污染事件,这是继英国疯牛病之后,再度因供应肉食品的养殖业的饲料出差错,造成欧洲乃至全球消费者又一恐慌。事件的发生是比利时养鸡业者发现的,母鸡生蛋率减少,蛋壳变硬,小鸡难以破壳而出,肉鸡也呈反常状态,因而怀疑饲料有问题,后在比利时的一家饲料公司生产的鸡饲料中,发现掺有含有二恶英的油脂饲料,检测其二恶英含量达７４１ｐｐｍ。主要原因是用了盛装工业用油的油桶来装了动物油脂,后经高温加热工艺而导致二恶英的产生。法国,比利时同时对比利时的…     

Dietary exposure to dioxins and dioxin-like PCBs of Hong Kong adults: results of the first Hong Kong Total Diet Study

Dioxins and dioxin-like polychlorinated biphenyls (PCBs) are persistent organic pollutants (POPs) covered by the Stockholm Convention on POPs. To assess the associated health risk of the Hong Kong population, the dietary exposure of the Hong Kong population and various age–gender subgroups to dioxins and dioxin-like PCBs was estimated in the first Hong Kong Total Diet Study (TDS), where food samples were collected and prepared “as consumed”. A total of 142 composite food samples, mainly foods of animal origin and their products and oily food, were analysed for polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) and dioxin-like PCBs by the high-resolution gas chromatograph/high-resolution mass spectrometer (HRGC/HRMS) system. Dietary exposures were estimated by combining the analytical results with the food consumption data of Hong Kong adults. The mean and 95th percentile exposures to dioxins and dioxin-like PCBs of the Hong Kong population were 21.9 and 59.7 pg toxic equivalent (TEQ) kg^?1 body weight (bw) month^?1 respectively, which amounted to 31.3% and 85.2% of the provisional tolerable monthly intake (PTMI). The main dietary source of dioxins and dioxin-like PCBs was “Fish and seafood and their products” (61.9% of the total exposure), followed by “Meat, poultry and game and their products” (20.0%) and “Mixed dishes” (6.95%). The study findings suggest that the Hong Kong population is unlikely to experience the major undesirable health effects of dioxins and dioxin-like PCBs.     

Mathematical model developed for environmental samples: prediction of GC/MS dioxin TEQ from XDS-CALUX bioassay data

Remediation of hazardous waste sites requires efficient and cost-effective methods to assess the extent of contamination by toxic substances including dioxin-like chemicals. Traditionally, dioxin-like contamination has been assessed by gas chromatography/high-resolution mass spectrometry (GC/MS) analysis for specific polychlorinated dibenzo-p-dioxins, dibenzofurans, and biphenyl congeners. Toxic equivalency factors for these congeners are then used to estimate the overall dioxin toxic equivalency (TEQ) of complex mixtures found in samples. The XDS-CALUX bioassay estimates contamination by dioxin-like chemicals in a sample extract by measuring expression of a sensitive reporter gene in genetically engineered cells. The output of the XDS-CALUX assay is a CALUX-TEQ value, calibrated based on TCDD standards. Soil samples taken from a variety of hazardous waste sites were measured using the XDS-CALUX bioassay and GC/MS. TEQ and CALUX-TEQ from these methods were compared, and a mathematical model was developed describing the relationship between these two data sets: log(TEQ) = 0.654 x log(CALUX-TEQ) + 0.058-(log(CALUX-TEQ))2. Applying this equation to these samples showed that predicted and GC/MS measured TEQ values strongly correlate (R2 = 0.876) and that TEQ values predicted from CALUX-TEQ were on average nearly identical to the GC/MS-TEQ. The ability of XDS-CALUX bioassay data to predict GC/MS-derived TEQ data should make this procedure useful in risk assessment and management decisions.     

Comparison of sulfuric acid treatment and multi-layer silica gel column chromatography in cleanup methods for determination of PCDDs,PCDFs and dioxin-like PCBs in foods

Two typical cleanup methods, sulfuric acid treatment and multi-layer silica gel column chromatography, for the determination of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dioxin-like PCBs) in seventeen food samples were examined and compared. Vegetables, fruits, cereals, fish, meat and dairy foods were extracted by conventional methods (shaking with acetone/n-hexane or with n-hexane after alkaline treatment). The extracts were cleaned up by sulfuric acid treatment or multi-layer silica gel column chromatography, followed by several column chromatographic steps. Of the samples treated, the vegetable, fruit and cereal samples could be directly applied to the multi-layer silica gel column after extraction. However, the samples containing fats and oils such as fish, meat and dairy foods needed to be treated several times with concentrated sulfuric acid before multi-layer column chromatography, because these samples plugged the column with oily residues. Both cleanup methods gave similar values of isomeric concentrations and showed similar efficiency of purification, and the recoveries ranged from 40 to 120%. These results are considered to provide useful data for the efficient analysis of dioxins in foods which have wide-ranging compositions.     

Cleanup of food samples with pre-packed multi-layer silica gel column for the analysis of PCDDs,PCDFs and dioxin-like PCBs

The cleanup procedure for the determination of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (PCBs) in food samples using a disposable pre-packed multi-layer silica gel column (multi-layer dioxin tube; D-tube) was evaluated. The blank test showed the need for conditioning of the column with n-hexane. To compare the method with the D-tube and the conventional method for the analyses of actual food samples, seven food samples (spinach, komatsuna, rice, salmon, beef, egg and butter) were extracted by shaking with acetone-n-hexane or n-hexane after alkaline treatment, and then the extracts were cleaned up by use of the D-tube or the prepared conventional column, followed by several column chromatographic steps. Both cleanup procedures gave similar values at each isomeric concentration level and showed similar efficiency with favorable recoveries. The results suggest that the D-tube is applicable to cleanup for the analysis of PCDD/Fs and dioxin-like PCBs in foods.     

Occurrence and biomagnification of polychlorinated naphthalenes and non- and mono-ortho PCBs in Lake Ontario sediment and biota

Biota and surface sediments collected from Lake Ontario were analyzed for polychlorinated naphthalenes (PCNs) and non- and mono-ortho-substituted polychlorinated biphenyls (n/ m-o-PCBs) to compare bioaccumulation behavior of these classes of dioxin-like chemicals in a food web from the Great Lakes. Mean sigmaPCN concentrations (tri-octaCN) ranged from 14 +/- 9 pg/g in plankton to 3500 +/- 3200 pg/g (wet weight) in lake trout while sediments contained from 21 to 38 ng/g (dry weight). Principal components analysis of PCN congener patterns indicated that chlorine substitution determined which congeners favored accumulation (e.g., CN-42, -52, -60, -66, -67, and -73), while others may be subject to metabolism. The bioaccumulative congeners exhibited similar trophic magnification factors (TMFs; 1.23-1.42) and biomagnification factors (BMFs; 5.5-8.6) to the n/m-o-PCBs for the trout/weighted diet relation, although BMFs for a benthic feeding relationship (slimy sculpin/Diporeia) indicated that the n/m-o-PCBs were more bioavailablethroughthe benthic pathway. PCNs contribute significantly to the burden of dioxin-like compounds in Lake Ontario biota, contributing between 12 and 22% of total PCN + PCB TEQ in lake trout and up to 69% in benthic organisms.     

Dietary intake of polychlorinated dioxins, furans and dioxin-like polychlorinated biphenyls from foods of animal origin in China

Four food groups of animal origin from the Chinese Total Diet Study (TDS) in 2000 were analysed for 17 polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (PCBs). The samples were from four regions, covering 12 provinces of China. PCDD/Fs, expressed as WHO toxic equivalents (TEQ), ranged from 0.02 to 0.28 pg TEQ g^-1 and dioxin-like PCBs ranged from 0.01 to 0.24 pg TEQ g^-1 (wet weight, ND = LOD), in all samples. Using food consumption data from a 3-day household dietary survey, daily dietary intake of dioxin-like compounds from foods of animal origin in China was estimated. Daily intake among regions ranged 0.09-0.59 pg TEQ kg^-1 body eight day^-1.     

Predicting toxicity equivalents in fish tissue

Toxicity equivalents is a measure of "dioxin-like" toxicity contributed by polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (dioxins), and polychlorinated dibenzofurans (furans). Calculation of toxicity equivalents require the use of analytical procedures that are expensive and slow, making them impractical for routine analysis. U.S. Environmental Protection Agency National Fish Tissue Study (2003) data were used to determine the most significant predictors of toxicity equivalents with multiple regression analysis. The strongest predictive model (P < 0.0001, R2 = 0.97) included five compounds (PCB-118; PCB-126; 2,3,7,8-TCDD; 1,2,3,6,7,8-HxCDD; 2,3,4,7,8-PeCDF). However, the required lower limit of detection for an analytical method measuring these congeners is 0.1 ppt and would not provide much benefit over the current analytical method. An alternative model (P < 0.0001, R2 = 0.68) that included three PCBs (PCB-138, PCB-153, PCB-118) would require a limit of detection of 1,000 ppt and be more practical. This research demonstrates that the measurement of selected compounds can be used to estimate toxicity equivalents and consequently serve as the impetus for the development of lower cost, rapid analytical methods for analysis of fish.     

Ah receptor agonist activity in frequently consumed food items.

The aryl hydrocarbon receptor (AhR) receives much attention for its role in the toxicity of dioxins and dioxin-like polychlorinated biphenyls. However, many other compounds have also been reported to bind and activate AhR, of which natural food components are of special interest from a human health perspective. Using the dioxin receptor-chemical-activated luciferase gene expression (DR CALUX) bioassay, extracts from many food items frequently consumed in the Netherlands were screened to estimate the intake of natural AhR agonists (NAhRAs). Using the prototypical AhR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as standard, it was estimated that the daily intake of NAhRAs might be considerably higher than the reported intake of dioxins and dioxin-like polychlorinated biphenyls. Potatoes, cruciferous vegetables, bread, hamburgers, and grapefruit juice contained most NAhRAs. Food preparation and acid treatment can show a significant effect on AhR activation. The interaction of natural and xenobiotic AhR agonists should be taken into account when performing risk-benefit analysis of both types of compounds.     

Ah receptor agonist activity in frequently consumed food items

The aryl hydrocarbon receptor (AhR) receives much attention for its role in the toxicity of dioxins and dioxin-like polychlorinated biphenyls. However, many other compounds have also been reported to bind and activate AhR, of which natural food components are of special interest from a human health perspective. Using the dioxin receptor-chemical-activated luciferase gene expression (DR CALUX) bioassay, extracts from many food items frequently consumed in the Netherlands were screened to estimate the intake of natural AhR agonists (NAhRAs). Using the prototypical AhR agonist 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) as standard, it was estimated that the daily intake of NAhRAs might be considerably higher than the reported intake of dioxins and dioxin-like polychlorinated biphenyls. Potatoes, cruciferous vegetables, bread, hamburgers, and grapefruit juice contained most NAhRAs. Food preparation and acid treatment can show a significant effect on AhR activation. The interaction of natural and xenobiotic AhR agonists should be taken into account when performing risk-benefit analysis of both types of compounds.     

二噁英、多氯联苯和氯丙醇的痕量与超痕量检测技术研究

为建立食品中二噁英、多氯联苯和氯丙醇的检测技术并达到国际水平，将稳定性同位素稀释质谱技术应用到中国食品安全和环境分析领域，针对不同目标化合物分别建立了高分辩磁质谱、四极杆低分辩质谱和离子阱串联质谱的标准化检测技术，特别是采用双同位素稀释同时测定4种氯丙醇的技术。通过对EPA1613A／1668A、FDA4084和EPSI／RM／31、AOAC2000．01等国际先进方法用食品（鱼、鱼油、鹿肉、奶粉和猪油）和环境样品（飞灰、土壤和底泥）开展对比筛选和一系列实验室闻协同性验证，确立了二噁英和多氯联苯的稳定性同位素稀释质谱检测方法，建立了用双稳定性同位素进行酱油中单氯取代和双氯取代氯丙醇同时测定的方法，提出了符合国际规范的技术方案，作为国家标准方法待颁布。利用该检测技术在中国首次开展鱼贝类和土壤中污染的二噁英和多氯联苯同系物类型特征指纹库研究和酱油中氯丙醇的大规模调查，获得了中国人群膳食二噁英毒性当量和氯丙醇摄入状况的暴露数据，不仅证明所建立的方法实用、可行，也为我国履行承诺摸清了家底，提供了依据。