双壳贝类养殖水体中Hg、Pb、Cd安全限量的研究

双壳贝类富集重金属会给消费者食用安全造成危害。本文以菲律宾蛤仔(Ruditapesphilippinarum)为研究对象,采用生物富集双箱动力学模型测定双壳贝类对3种重金属Hg、Pb、Cd的生物富集动力学参数。结果表明:贝类对重金属的生物富集和排出都较缓慢,经过30d生物富集未达到稳态平衡,Hg、Pb、Cd的生物富集系数BCF分别为1030、935和378,生物半衰期处在18～33d范围内。参考欧盟和我国菲律宾蛤仔标准中关于Hg、Pb、Cd的安全限量,通过BCF计算得到菲律宾蛤仔养殖水体中Hg、Pb、Cd的安全限量分别为0.0005、0.01和0.026mg/L。     

重金属Cd与Cu在克氏原螯虾体内富集与释放规律

研究克氏原螯虾分别在Cd2+质量浓度为0、0.05、0.10 mg/L和Cu2+质量浓度为0、0.5、1.0 mg/L的单一水环境中暴露时,肝胰腺、鳃和肌肉对Cd和Cu的生物富集和释放特性。通过非线性拟合得到克氏原螯虾对Cd和Cu的生物富集动力学参数：富集速率常数k1、排出速率常数k2、生物富集系数（bioconcentration factors,BCF）和生物半衰期（T1/2）,并得出理论富集平衡状态时生物体内Cd和Cu富集量（ρAmax）。结果表明：克氏原螯虾的肝胰腺和鳃对水体中Cd2+和Cu2+都有很强的富集特性,且富集量与富集时间、水体中Cd2+和Cu2+的质量浓度成正相关;肌肉组织中富集规律则不明显。同种重金属在不同组织中的富集量不同,即重金属富集具有组织选择性：在分别含Cd2+和Cu2+的水体中暴露实验9 d后,3 种组织对Cd的富集量顺序为鳃＞肝胰腺＞肌肉;对Cu的富集量顺序为肝胰腺＞鳃＞肌肉。克氏原螯虾对Cu和Cd的富集代谢都较缓慢,暴露9 d仍未达到稳定。克氏原螯虾体内Cd和Cu的BCF范围分别约为2～207、3～226;T1/2分别约为3～29、7～36 d;在理论平衡状态下,鳃、肝胰腺和肌肉中Cu和Cd的ρAmax随着环境中Cu2+和Cd2+质量浓度的增大而增大,且呈正相关。     

台州近岸海域水质、沉积物和贝类体内镉含量的初步调查

2009年10月至2014年8月对台州近岸海域贝类养殖区的水质、泥质及贝类自身体内的重金属镉含量进行监测,并根据《渔业水质标准》(GB11607-1989)以及《海水水质标准》(GB 3097-1997)(II类),对水质进行评价,结果表明水质中重金属镉含量均低于标准值5ug/L,适合养殖;根据《海洋沉积物质量》(GB 18668-2002)(第一类),沉积物中重金属镉含量均低于标准值5mg/kg;根据《食品安全国家标准食品中污染物限量》(GB2762-2012),对泥蚶、缢蛏体内重金属镉的污染程度进行评价,结果表明蛤、缢蛏、贻贝均没有超标,泥蚶的超标情况相对比较严重。     

中药渣及袋栽平菇中重金属含量的研究

用原子吸收分光光度法对药渣及用药渣栽种的平菇中重金属元素铅、铜、镉含量进行了测定,并用单项累积污染超标倍数Pe进行评价。结果表明:药渣中铜、铅、镉均被检出,铜的平均含量为14.32 mg/kg,镉的平均含量为0.212 5 mg/kg,均低于中国药典2005版和绿色行业标准的限量标准;铅平均含量为8.356 mg/kg,高于中国药典2005版和绿色行业标准1.67倍,其单项累积污染超标倍数Pe为0.67。用药渣栽种的平菇(试验组)中重金属铅、镉均未检出,说明平菇对药渣中的铅未产生富集现象,铜平均含量为9.199 mg/kg,低于国家食品(蔬菜、食用菌)卫生限量标准,平菇中铜、铅、镉含量是安全的。     

菲律宾蛤仔(Ruditapes philippinarum)养殖水体中石油烃安全限量的研究

石油烃污染是影响双壳贝类食用安全的重要因素。文中以菲律宾蛤仔(Ruditapes philippinarum)为研究对象,采用半静态动力学富集实验探讨了双壳贝类对养殖水体中石油烃的富集规律。结果表明,经过4 d,石油烃在贝体和水环境之间达到稳态平衡;生物富集系数(BCF)为545;石油烃浓度为0.068 mg/L的水体组,富集平衡后贝体内的石油烃含量高于菲律宾蛤仔的石油烃异味阈值(25~30 mg/kg),其它水体组则相反。参考USEP-A、GB18421-2001等关于双壳贝类中石油烃安全限量的规定,经讨论贝体内石油多环芳烃的毒力代谢机理后,判定菲律宾蛤仔养殖水体中石油烃的安全限量定为0.05 mg/L较为合理。     

南通市水产品中铅、镉含量分析与评价

了解南通市水产品中重金属的含量水平及卫生品质状况。2017年在南通市区范围内采集具有代表性的水产品,4类共440份样品,进行铅、镉含量检测,并采用单因子污染指数法对重金属污染等级及污染水平进行评价。南通市区4类水产品中铅、镉指标均有检出;鱼类、贝类、头足类铅、镉含量符合《无公害食品水产品中有毒有害物质限量》限量标准;甲壳类铅、镉均有超标,梭子蟹超标率最高,超标率分别为9.1%和18.2%。研究可为南通市水产品品质安全评价提供依据,为进一步研究重金属污染来源、富集及转移规律提供参考。     

紫贻贝(Mytilus edulis)不同组织对镉的生物富集及释放特征

目的:探索紫贻贝不同器官对镉(Cd)的富集吸收及释放特征。方法:以紫贻贝为研究对象,采用静态水交换法进行染毒,原子吸收光谱检测Cd在紫贻贝不同器官中的含量变化情况。结果:富集第15 d,紫贻贝内脏团、前闭壳肌、后闭壳肌、外套膜和鳃中,Cd含量依次为145.560、11.826、28.143、22.394、66.113 mg/kg。4种器官对Cd的吸收速率常数(k),在富集初期较高、中期有所减弱、后期再次升高;生物富集系数(BCF)随暴露Cd浓度增加而逐渐减小,且均表现为内脏团鳃后闭壳肌外套膜前闭壳肌。4种器官Cd量与富集时间之间关系,均符合Harris模型(Y=1/(a+b Xc)),拟合R2范围为0.9286~0.9890。在释放阶段,4种器官中Cd含量均未表现出显著性下降趋势(p0.05)。结论:紫贻贝对Cd具有较强的生物富集能力,而其自然代谢释放能力较弱,为典型Cd净积累型生物。     

浒苔对镉、铅和铝的生物富集动力学研究

本文研究了浒苔对镉、铅和铝的富集作用,在各养殖池中添加Cd2+(5、20、80μg/L),Pb2+(5、20、80μg/L)和Al3+(5、20、80μg/L),利用电感耦合等离子体质谱法(ICP-QMS)测定浒苔中Cd、Pb和Al的含量,并对其变化进行非线性拟合,获取动力学参数。结果表明:浒苔对Cd、Pb和Al的富集与暴露浓度呈正相关关系;Cd和Pb的富集符合双箱动力学模型,而Al符合Logistic动力学模型。其中浒苔中Cd的双箱模型回归富集速率常数Ka为418.68、234.30和105.57,富集系数为1785.12、1429.67和625.69;Pb的富集速率常数Ka为1257.30、768.81和863.83,富集系数11028.95、50249.08和9119.79;浒苔中Al的Logistic模型回归富集速率常数0.39、0.42和0.46。浒苔对镉、铅和铝三种重金属具有较强的富集作用,双箱动力学模型可显著预测Cd和Pb的富集,Logistic模型可显著预测Al的富集。     

大米重金属含量及其食用的健康风险分析

对天津市市售大米进行了重金属含量调查分析,并通过经大米途径重金属暴露接触对人体的健康危害进行风险分析。结果表明,大米中铅、镉、砷和汞的平均含量分别为0.077 8,0.062 7,0.027 3和0.008 7 mg/kg。所采集的大米重金属含量与GB 2715—2005"粮食卫生标准"和NY 5115—2002"无公害食品大米"规定限量标准相比较,铅、镉、砷和汞的含量均低于标准规定的限量值,表明天津市市售大米总体水平是安全的。重金属暴露接触对人体的健康风险分析结果表明,4种重金属元素铅、镉、砷和汞的靶标危害指数(THQ)值均低于1,说明经大米途径摄入的铅、镉、砷和汞对居民的健康危害风险较低。但是THQ成人THQ儿童,表明成人经大米暴露途径摄入重金属的潜在健康风险较高。     

浙江温州地区海产品中石油烃的含量分析及膳食风险评估

目的 掌握浙江温州地区海产品中石油烃的污染状况及其对人群膳食暴露影响。方法 采集2022年浙江温州地区30个品种217批次海产品, 取各样品可食部分, 经组织匀质后, 经6 mol/L氢氧化钠溶液40℃恒温振荡皂化6 h、二氯甲烷萃取、旋转蒸发浓缩至干、脱芳石油醚复溶, 取上清液采用分子荧光仪测定其石油烃含量。采用单因子指数法和商值法分别评价其污染程度和膳食暴露健康风险。结果 所有海产品均存在不同程度的石油烃检出(范围1.06~26.6 mg/kg, 均值9.70 mg/kg), 其中13.4%的样品中石油烃含量超出NY 5073—2006《无公害食品水产品中有毒有害物质限量》中规定的限值, 分别为缢蛏、泥蚶、馒头蟹。总体上检出浓度依次排序, 养殖贝类>海捕头足类>海捕蟹>海捕虾>海捕鱼>养殖藻类。所测海产品石油烃危害商在0.01226~0.3076之间, 均小于1, 致癌风险指数范围为4.9×10-7~7.6×10-5, 小于1×10-4, 其中养殖贝类中缢蛏、泥蚶、贻贝的危害商和致癌风险指数相对较高。结论 浙江温州地区海产品中石油烃的健康风险较低, 但应密切关注长期或大量食用缢蛏、泥蚶、贻贝带来的不利影响。     

Mineral contents of some southern Italian wines. II. Determination of Li, Na, Mg, K, Ca, Co, As, Rb, Sr, Ag, Sb, Ba

Following our study of the mineral contents of some Southern Italian wines, this work reports on the detection of 12 elemental components. The elements were determined using ICP-AES, flame atomic emission or absorption spectroscopy. The values determined for Li, Na, Mg, K, Ca, Rb, Sr and Ba were within the usual ranges for wines (average values for these elements were: 0.010, 26.2; 94.4; 888; 94.0; 3.30, 0.82 and 0.11 mg/l respectively). All the wines contained low levels of As, the concentrations of which were always under 0.20 mg/l, the maximum level permitted by E.E.C. standards. The measuring of Co, Ag, and Sb led us to ascertain, in all the wines, concentrations lower than 0.01 mg/l for Co and Ag and below the instrumental detection level for Sb (0.06 mg/l). In a previous study wines from D.O.C. areas of Southern Italy were analysed by the technique of inductively coupled plasma atomic emission spectroscopy (ICP-AES), for 14 minerals. This paper deals with further investigation of the mineral composition of the same wines for different metal constituents, analysed by ICP-AES, flame atomic emission, or atomic-absorption spectroscopy (two techniques). The first technique was applied to the detection of Co, As, Sr, Ag, Sb, and Ba. The alkaline metals Li, Na, K, and Rb were determined by flame atomic emission, a technique which possesses better detection limits for these elements. For Mg and Ca the atomic absorption methods were applied.     

Isolation,Composition, Structure,Properties, Modifications,and Uses of Yam Starch

Starch is the major carbohydrate in yam tubers and can amount up to 80% of the dry matter. The starch quality determines the quality of food and industrial products made from yam tubers. This review summarizes the present knowledge of the isolation, composition, structure, property, modifications, and uses of starches from diverse yam species. Compared with other tuber and root starches, there is a lack of systematic information on the yam starches. This hinders the further development of yams as sustainable crops as well as the value‐added processing of the starches. Therefore, suggestions on how to better understand and utilize these starches are provided.     

卷烟中锂、铬、镍、铜、砷、硒、钼、镉、铊和铅含量分析

采用微波消解-电感耦合等离子体质谱法测定了41个牌号烤烟型卷烟和雪茄烟样品烟丝中的锂、铬、镍、铜、砷、硒、钼、镉、铊和铅含量,并按照类型和价位对卷烟中这10种有害元素含量进行了统计分析。结果发现:①卷烟中锂和铜的含量较高,铊的含量很低,铬、镍、镉、铅、砷、硒和钼7种元素的平均含量为0.55～4.42μg/g;②雪茄烟中铬、镍、砷、钼、镉、铊和铅的含量一般高于烤烟型卷烟,而硒元素的含量则相反,但差别较小;烤烟型卷烟中锂和铜的含量与雪茄烟没有显著差异;③高档卷烟中的锂、镍、镉、铊和铬含量较低,而砷、铅的含量较高;不同价位卷烟的铜、硒和钼含量差异不显著。     

Survey of trace elements (Al,As, Cd,Cr, Co,Hg, Mn,Ni, Pb,Se, and Si) in retail samples of flavoured and bottled waters

Concentrations of eleven trace elements (Al, As, Cd, Cr, Co, Hg, Mn, Ni, Pb, Se, and Si) were measured in 39 (natural and flavoured) water samples. Determinations were performed using graphite furnace electrothermetry for almost all elements (Al, As, Cd, Cr, Co, Mn, Ni, Pb, and Si). For Se determination hydride generation was used, and cold vapour generation for Hg. These techniques were coupled to atomic absorption spectrophotometry. The trace element content of still or sparkling natural waters changed from brand to brand. Significant differences between natural still and natural sparkling waters (p < 0.001) were only apparent for Mn. The Mann–Whitney U-test was used to search for significant differences between flavoured and natural waters. The concentration of each element was compared with the presence of flavours, preservatives, acidifying agents, fruit juice and/or sweeteners, according to the labelled composition. It was shown that flavoured waters generally increase the trace element content. The addition of preservatives and acidifying regulators had a significant influence on Mn, Co, As and Si contents (p < 0.05). Fruit juice can also be correlated to the increase of Co and As. Sweeteners did not provide any significant difference in Mn, Co, Se and Si content.     

The effect of storage of canned juices on content of the metals Fe, Cu, Zn, Pb, Sn, Al, Cd, Sb and Ni

The increase in concentration of iron, copper, zinc, lead, antimony, aluminium, cadmium, tin and nickel over a 2 year's time of juices of peach (prunus persica), pear (pyrus communis), apricot (prunus vulgaris) and apple (malus pumila) was determined. The results show a considerable increase in Fe, Cu, Pb, Zn and Sn with time, while the change in Al, Cd, Ni and Sb is negligible.     

Analysis of cheese for histamine, tyramine, tryptamine, histidine, tyrosine, and tryptophane

A method is described for determining the content of selected biologically active amines (histamine, tyramine, tryptamine) and amino acids (histidine, tyrosine, tryptophane) in cheeses by high performance liquid chromatography. The amines and amino acids were quantified by employing a counter ion-containing mobile phase and by comparing peak areas of high performance liquid chromatography charts for sample cheeses versus standard cheeses containing known amounts of added amines based on dual injections of samples and standards. Recovery of amines and amino acids varied from 87.5 to 111%. Histamine, which has been associated with food poisoning in concentrations of 185 mg/100 g in Swiss cheese and 180 to 500 mg/100 g in fish, was found in concentrations above 500 mg/100 g in Swiss cheese. The high performance liquid chromatography analytical method should be useful for screening to detect cheese samples containing toxic amounts of histamine and for research studies designed to determine the cause and effect relationships for histamine production in cheese.     

In Vitro Digestion of Raw,Roasted, and Pressure-Flaked Corn, ,

We compared raw, roasted, and pressure-flaked com in dry matter and starch digestion studies in vitro. For dry matter digestion, incubations were 1, 4, 8, 16, 24 and 48 h. Dry matter digestion was increased in hours 1 through 24 by processing. Digestion in the 48-h period was decreased by processing which suggests that processing may increase the ease of utilization but not total utilization. Roasting decreased 48-h dry matter digestion more than pressure flaking. Starch digestion with incubations 1, 4, 24, and 48 h favored processed corn at all hours except 4. The 48-h observations from both studies indicate that while processing enhances starch utilization, it impairs utilization of other components in the grain. Prediction equations for dry matter and starch digestion for each corn treatment from length of incubation period and squared length of incubation period had multiple correlations of .96 or greater.     

Mineral contents of some southern Italian wines I. Determination of B, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Sn, Pb by inductively coupled plasma atomic emission spectrometry (ICP-AES)

Summary Using a new analytical technique, the inductively coupled plasma atomic emission spectroscopy (ICP-AES), 51 red and rose wines from D.O.C. areas of Southern Italy were measured for the following 14 elements: B, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Sn, Pb.Among these elements the most abundant were Si with an average value of 19.60 mg/l, Fe 5.87 mg/l, B 5.19 mg/l, Al 2.13 mg/l and Mn 1.40 mg/l; Cu, Zn and Sn were present in average quantities between 0.10 and 1.00 mg/l; the remaining elements had average concentrations below 0.10 mg/l.

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Gehalt an Spurenelementen in einigen D.O.C.-Weinen aus Süditalien I. Quantitative Bestimmung von B, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Sn, Pb durch ICP Atomemissions-Spektrometrie

Zusammeufassung Unter Anwendung emer neuen analytischen Methode, ICP Atomemissions-Spektrometrie, wurden in 51 Rot- und Rosé-D.O.C.-Weinen aus Süditalien, die folgenden 14 Elemente bestimmt: B, Al, Si, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Sn, Pb.Unter diesen Elementen sind Si mit einem Mittelwert von 19,60 mg/l, Fe mit 5,87 mg/l, B mit 5,19 mg/l, Al mit 2,13 mg/l und Mn mit 1,40 mg/1 die häufigsten. Die mittleren Konzentrationswerte für Cu, Zn und Sn liegen zwischen 0,10 und 1,00 mg/l; während die der restlichen Elemente unter 0,10 mg/l sind.

     

Varied Composition of Tocochromanols in Different Types of Bran: Rye,Wheat, Oat,Spelt, Buckwheat,Corn, and Rice

The profiles of tocopherol (T) and tocotrienol (T3) homologues in 37 samples of seven different types of bran (rye, wheat, oat, spelt, buckwheat, rice, and corn), available on the Polish market, were studied. Tocochromanols were identified and quantified by reverse phase-high-performance liquid chromatograph/fluorescence detector and reverse phase-ultra performance liquid chromatography-electrospray ionization/mass spectrometry. Only rice bran contained all eight tocochromanol types. Corn bran lacked β-T3; rye, wheat, oat, and spelt bran lacked γ-T3 and δ-T3; and buckwheat bran lacked β-T3, γ-T3, and δ-T3. In buckwheat and corn bran tocopherols predominated (98 and 78%, respectively); whereas rye, wheat, oat, spelt, and rice bran were rich in tocotrienols (78, 76, 66, 87, and 66%, respectively). The average total tocochromanol contents in the oat, corn, spelt, buckwheat, wheat, rye, and rice bran were 5.5, 16.2, 15.8, 14.7, 12.8, 10.7, and 9.1 mg/100 g of dry weight, respectively. Tocochromanol concentrations in samples of the same type bran from different sources varied considerably. Better labeling of bran products to reflect this variation would assist with control of vitamin E daily dietary requirements.