皮革中铅镉含量的测定

试样用硝酸镁助灰干法消解 ,火焰原子吸收法测定皮革中铅、镉含量。铅、镉相对标准偏差分别为 :8.3% ,11.6 % ;加标回收率分别为 :84 .2 % - 93.5 % ,88.2 % - 91.3%。     

The European maximum level for cadmium in bovine kidneys is in Belgium only realistic for cattle up to 2 years of age

The effect of animal age on concentrations of cadmium, lead, arsenic, copper and zinc in bovine tissues (meat, kidney and liver) sampled from animals reared in contaminated areas or reference regions in Belgium was investigated. For cadmium concentrations in meat samples analysis of variance (ANOVA) showed an increasing trend with age. In addition, a significant positive linear relation (p < 0.05) was found between animal age and renal (R ² = 0.56) or hepatic (R ² = 0.39) cadmium levels. Lead concentrations in kidneys and liver also increased with age, but the effect was blurred, likely due to the internal remobilization of lead. For the other trace elements (arsenic, copper, zinc) no relationship could be found between their concentration in meat, kidneys or liver and animal age. Renal cadmium concentrations were predicted for bovines at different ages by using the slope of the linear regression equation, and by taking into account its 95% confidence interval. Calculations for 2-year-old animals from reference areas showed that in this group the European maximum level of 1 mg kg^?1 for cadmium in kidneys would be exceeded in zero to 5% of cases. If a general rejection percentage of maximum 5% would be desirable for kidneys sampled in the reference areas (according to the ALARA principle–‘as low as reasonably achievable’–of European Union policy), then (1) kidneys from animals older than 2 years from the reference areas should a priori not be considered suitable to be placed on the market, or (2) the maximum level for cadmium in kidneys should be increased to 3 mg kg^?1. The latter would bear negligible risks for the general population and the majority of high-level kidney consumers. On the other hand, bovine kidneys from the most contaminated areas are not suitable to be brought into the food chain because it is predicted that the maximum level is already exceeded by more than 5% of the 1-year-old animals.     

Effect of thermal processing and canning on cadmium and lead levels in California market squid: the role of metallothioneins

The effects of two common seafood preparation practices (roasting and industrial canning) on the heavy metal content – cadmium (Cd) and lead (Pb) – of various tissues of California market squid were studied. Emphasis was placed on the role of metallothioneins (MT) in Cd and Pb behaviour during processing. Cd and Pb analysis was conducted by a Zeeman GTA-AAS atomic absorption spectrometry system; MT analysis was performed by a mercury saturation assay. Results showed that Cd levels in the mantle and whole squid were considerably affected by both processing practices, reaching a 240% increase in mantle and a 40% increase in whole squid. Interestingly, Cd behaviour was associated with MT changes during squid processing. On the other hand, Pb content was not affected from either processing or associated with MT content in the raw or processed squid. Therefore, processing operations may affect Cd and Pb content differently due to the specific metal bioaccumulation and chemical features of each heavy metal type.     

2012—2016年内蒙古地区主要食品中铅镉总汞污染调查分析

目的 了解内蒙古地区食品中铅、镉、总汞的污染水平,为及时发现食品安全隐患和进行风险预警提供基础数据。方法 按照2012—2016年内蒙古自治区食品中化学污染物监测计划,结合内蒙古地区地产食品种类及分布特点,采集内蒙古地区12个盟市的本地产食品样品,采用国家食品安全标准方法对样品中铅、镉、总汞进行检测,按照食品污染物限量标准进行评价。结果 共采集8类食品,其中监测铅含量的有效样品为4 212份,检出率为32.72%(1 378/4 212),超标率为0.76%(32/4 212),超标的食品类别主要为食用菌(以鲜食用菌计),超标率为7.37%(14/190);监测镉含量的有效样品为4 173份,检出率为54.18%(2 261/4 173),超标率为0.58%(24/4 173),超标的食品类别主要为食用菌(以鲜食用菌计)、水产动物及其制品及肉与肉制品,超标率分别为3.68%(7/190)、2.06%(9/437)及1.15%(6/524);监测总汞含量的有效样品为4 217份,检出率为32.68%(1 378/4 217),超标率为0.50%(21/4 217),超标食品主要为食用菌(以鲜食用菌计)及蔬菜,超标率分别为3.68%(7/190)与1.01%(11/1 088)。结论 内蒙古地区生产的食用菌(以鲜食用菌计) 、水产动物及其制品、肉与肉制品、蔬菜中存在重金属污染情况,应引起高度重视。     

苏州市场大米中重金属铅、镉、铬含量比较

大米是人类赖以生存的主食之一,随着工业化进程的加快,稻米种植土壤的重金属污染越来越严重,该文对苏州市场中产区分别为华东和东北地区的37个大米样品进行了重金属铅(Pb)、镉(Cd)、铬(Cr)的分析。实验结果证实东北产区的大米的铅、镉含量跟华东地区的比在均值的95%置信区间具有显著差异,而铬含量无显著差异。东北地区产的大米的平均铅、镉含量比华东地区的低。     

Cadmium and lead content in fresh and canned peas

Cadium and lead in raw, blanched and canned peas were determined using atomic absorption spectrophotometry. The daily intake of cadmium and lead from peas in Spain was evaluated. The cadmium content of the peas ranged from less than 0.004 to 0.015 μg^?1, whereas the lead content varied from 0.49 to 0.223 μg^?1. The concentraiton of both elements was compared at different stages of the process. Statistically significant differences were found in the lead levels as a function of size and the different stages of the canning process. The mena level of cadmium and lead (0.041 μgg^?1 and 0.092 μgg^?1 respectively) could account for a daily intake of 0.1 μg day^?1 for cadmium and 1.1 μg day^?1 for lead.     

微波消解石墨炉原子吸收法测定大米中铅镉

采用微波消解—石墨炉原子吸收法对大米中的铅、镉进行了测定,并与常规湿法消解方法进行了比较。利用国家标准物质杨树叶、甘蓝验证了方法的准确度与精密度。结果表明,采用微波消解法,方法准确度为95．0％～105%,精密度为2．8％～8．4%,该方法能够满足食品分析的要求。     

The influence of industrial-scale canning on cadmium and lead levels in sardines and anchovies from commercial fishing centres of the Mediterranean Sea

The current study encompassed a survey on the levels of toxic trace elements in two highly consumed fish species in commercial fishing centres of western, central and eastern Mediterranean Sea. A Zeeman GTA-AAS graphite furnace atomic absorption spectrometry system was used throughout the study. Toxicological evaluation of the samples revealed a low Cd content in the raw samples, ranging between 0.003 and 0.027?mg?kg^?1. Pb presented significantly higher values, from 0.037 to 0.297?mg?kg^?1, occasionally reaching the limit of 0.3?mg?kg^?1. Heavy metal levels were particularly higher in bones, thus raising queries about the safe consumption of fish intended to be eaten as a whole, a very common practice for small fish and canned products. The influence of industrial-scale canning showed that canning enhanced heavy metal levels by 35%–80%. The effect of canning depended on metal type and reduction of moisture loss after the steam-roasting step of the canning procedure.     

新鲜猪肉中痕量铅、镉的微波消解法快速测定

猪肉样品用硝酸及过氧化氢消解并采用微波加热，试液中铅和镉用GF—AAS法测定，所得分析结果与常规法相比，具有更好的准确度和精密度。此方法的操作更简便、快速。     

Cadmium concentrations in the liver of 10 different pig genetic lines from Vojvodina,Serbia

Cadmium concentrations were determined in 480 liver samples from 10 different pig genetic lines produced in Vojvodina (Serbia). Cadmium levels were determined by flame atomic absorption spectrometry after mineralization by dry ashing. The difference in cadmium levels in analysed liver tissues was not significant (p?>?0.05) between the various genetic lines. However, large variations in cadmium levels (from 0.03 to 0.27?mg/kg) in liver tissues indicated its availability in the local agricultural environment in Vojvodina. The average level of cadmium (0.13?mg/kg) was higher than the levels reported in pork liver from some developed countries.     

微波消解法提取玉米中铅镉含量的条件优化

目的优化微波消解法提取玉米中重金属铅镉的消解条件,并采取石墨炉原子吸收法测定其中的铅镉含量。方法以硝酸与过氧化氢比值及微波消解仪第3个阶段的温度、升温时间、保持时间为4个研究因素,对玉米实验材料和标准样品进行微波消解,以回收率为评价指标,通过正交试验确定在检测玉米中铅镉含量时微波消解的最佳条件。结果在处理玉米样品时,微波消解的最佳条件是硝酸和过氧化氢用量比为6:2(V:V),微波消解第3阶段温度为200℃,升温时间为8 min,保持时间为12 min。经方法学验证,发现优化方法的相对标准偏差为1.05%～1.21%,回收率为95.1%～96.8%。结论此优化方法处理玉米样品节省时间,消解完全,同时能够提高检测结果的准确度和精密度,适合大批量玉米样品中铅镉的检测。     

江西赣南地区脐橙中镉、铬、铅的测定

应用电感耦合等离子体质谱法测定了江西赣南地区脐橙的根、枝、叶、皮及果实中镉、铬、铅等元素,采用微波消解,直接测定.其方法检出限低,准确度好.为进一步研究脐橙与镉、铬、铅关系,提供了很好的分析方法和信息.     

阳极溶出伏安法同时测定高盐调味品中铅镉

采用湿法消解结合阳极溶出伏安法对沾水辣、酱油和鱼露等高盐调味品中铅镉的测定进行了方法研究。探索了仪器条件、电解质及其用量、高盐对铅镉的影响,并对酸类型及酸度的干扰、共存离子干扰进行了实验。铅、镉工作曲线的线性范围分别为2⁵0、1²0μg·L^-1,相关系数分别为0.9999和1.0000,仪器检出限为铅0.043μg·L^-1、镉0.029μg·L^-1,方法检出限为铅2.17μg·kg^-1、镉1.43μg·kg^-1。该方法测定实际样品中铅、镉含量的精密度分别为1.11%⁴.66%、0.69%⁵.34%,加标回收率分别为93.9%¹09.9%、94.7%¹07.5%。结果表明方法简便、灵敏,具有较好的选择性和可靠性。      

半消解悬浮液进样测定粮食样品中镉、铅、总砷含量

对粮食样品半消解条件、悬浮液选择、石墨炉程序升温条件、基体干扰等进行研究,建立了半消解悬浮液进样–石墨炉原子吸收光谱法测定粮食样品中镉、铅与砷含量的方法。结果表明,采用标准加入法,将粮食样品进行低温半消解,加入悬浮溶液(0.2%硝酸+0.1%Triton X–100),石墨炉程序升温增加了450℃步骤在空气条件下去除样品基体,得到了良好分析结果,镉、铅以及砷的相对标准偏差(RSD)均小于5%,镉、铅以及砷样品检出限分别为0.20、10.4、11.0μg/L。采用该法测定国家大米标准物质的镉、铅以及砷含量与标准物质证书的结果吻合。因此该法适用于粮食样品中镉、铅与砷的快速测定。     

苏南与苏北地产粳稻谷中铅和镉含量的分析对比

粳稻是江苏省内主要种植的粮食之一,随着苏北工业化进程的加快,苏北地产的粳稻将与苏南一样,面临的重金属污染风险越来越大.对江苏省内稻谷主产区——苏北和苏南产的35个粳稻谷中重金属铅、镉的含量进行分析和研究,结果表明,苏北产粳稻谷中的铅、镉含量与苏南产的相比,在99％的水平上具有显著差异;苏北产粳稻谷中铅、镉平均含量低于苏南产,但所有样品的铅含量均符合国标GB2762 2005要求,镉含量大多符合国标GB 2762-2005要求;苏北地区的粳稻谷中重金属污染风险相对苏南的小.     

便携式X射线荧光光谱法检测大米中的镉

食品中的重金属对人体危害较大,尤以镉毒性最大.以大米为研究对象,建立了X射线荧光与干法灰化相结合检测大米中镉的新方法.通过采用快速灰化预处理,将大米中的镉富集到一定程度后把灰分装入专用样品测量杯,再使用便携式X射线荧光光谱仪对大米中的镉进行检测.使用该方法对实际样品进行检测,检测结果与传统的微波消解石墨炉原子吸收光谱法结果基本一致,具有良好的准确度,说明该方法可以用于镉大米快速筛查.方法的检测限为0.072 mg/kg,单次测试过程所需要的时间约为13 min.该方法相较于传统方法具有操作简单、耗时短的特点,可为镉超标的大米提供一种快捷的筛选方法.     

陶瓷食品包装材料中铅、镉向真实食品的迁移研究

陶瓷食品包装容器中的有害重金属铅、镉向食品的迁移会造成食品污染进而危害消费者身体健康。本文通过制备含有铅、镉这两种重金属元素的陶瓷样品,使之分别在20℃和40℃的条件下与白酒、黄酒、醋和酸豆角汁这四种真实食品接触一定时间来研究这两种重金属的迁移行为。结果表明:铅、镉迁移量随着温度的升高而增加,并且迁移速率也与温度成正比;铅、镉的迁移量受食品的pH影响,pH越低,迁移量越高;铅的迁移量还与酒精度成反比,酒精度越高,铅的迁移量越少。      

Elements in rice from the Swedish market: 1. Cadmium, lead and arsenic (total and inorganic)

A survey of the levels of cadmium, lead and arsenic in different types of rice available on the Swedish retail market was carried out in 2001-03. The types of rice included long and short grain, brown, white, and parboiled white rice. The mean levels found were as follows: total As: 0.20 mg kg^-1, inorganic As: 0.11 mg kg^-1; Cd: 0.024 mg kg^-1; and Pb: 0.004 mg kg^-1. ICP-MS was used for the determination of As (total and inorganic) after acid digestion. Lead and cadmium were determined using graphite furnace atomic absorption spectrometry (GFAAS) after dry ashing. In countries where rice is a staple food, it may represent a significant contribution in relation to the provisional tolerable weekly intake for Cd and inorganic As.     

Elements in rice from the Swedish market: 1. Cadmium,lead and arsenic (total and inorganic)

A survey of the levels of cadmium, lead and arsenic in different types of rice available on the Swedish retail market was carried out in 2001–03. The types of rice included long and short grain, brown, white, and parboiled white rice. The mean levels found were as follows: total As: 0.20 mg kg^?1, inorganic As: 0.11 mg kg^?1; Cd: 0.024 mg kg^?1; and Pb: 0.004 mg kg^?1. ICP-MS was used for the determination of As (total and inorganic) after acid digestion. Lead and cadmium were determined using graphite furnace atomic absorption spectrometry (GFAAS) after dry ashing. In countries where rice is a staple food, it may represent a significant contribution in relation to the provisional tolerable weekly intake for Cd and inorganic As.     

Determination of zinc,cadmium, lead and copper in pellets and pulp of sugar beet

Pulp is a residual product of the sugar industry resulting from the total extraction of sugar contained in the root of sugar beet and is normally used in the form of pulp or pellets as food in the cattle industry. The objective of this work was the simultaneous determination of zinc, cadmium, lead and copper in pellets and dried pulp. For this we have developed a method of analysis using anodic stripping voltammetry in the differential pulse mode (DPASV) at a hanging mercury drop electrode (HMDE) and compared the results with those obtained by means of electrothermal atomic absorption spectrometry (ETAAS). We conclude that DPASV can be used as an alternative method to ETAAS to determine low concentrations of Zn, Cd, Cu and Pb in such samples, having the advantage of allowing the determination of all four metals simultaneously. From the analysis of real samples it can be concluded that Zn is present in the highest concentration, ranging from 3 to 30 mg kg^?1, while Cd, Pb and Cu concentrations were always lower than 1, 8 and 8 mg kg^?1 respectively. Copyright © 2005 Society of Chemical Industry