催化比色法在研制“两种海带(茶叶)中碘成分分析标准物质”中的应用

改进后的催化比色法 :K2 CO3 —ZnSO4存在下样品高温灰化 ,离心取上清试液。在KCNS— (NH4)Fe(SO4) 2 —NaNO2 体系中 ,利用碘离子催化NaNO2 还原Fe(CNS) 3 ,使桔黄色的Fe(CNS) 3 褪色。碘标准曲线回归方程式Y =1 0 92 1- 0 0 12 8X。该方法于标准物质均匀性试验中说明该两种标准物质是均匀的 ;在标准物质稳定性试验中 ,表明该两种标准物质是稳定的。对低、中碘量标准物质中碘的测定均值分别为 8 9、83 6μg/g。     

灵芝中锗成分分析标准物质的研制

目的是为有关行业对锗分析、监测及评价结果的准确一致而设计和制备，可用于有关行业的技术培训、考核、仲裁、验证等工作。本标准物质用石墨炉原子吸收光谱法等三种以上不同原理、不同分析分析方法进行定值。按格拉布斯法则判定每组数据，正态性Ｄ检验确认７组定值的所有数据为正态分布后，总算术平均值为０．３８μｇ／ｇ，标准偏差为０．０８μｇ／ｇ。     

全自动碘分析仪测定尿碘和盐碘的研究

目的 为获得一种快捷高效、准确灵敏的测定尿碘和盐碘检测方法。方法 借助恒温干燥箱消解尿样和盐样，应用Autochem 3100全自动碘分析仪进行定量检测。结果 尿碘方法在含碘量0μg/L～300μg/L标准曲线范围内吸光度的对数与浓度成线性，相关系数r绝对值>0.999 0,检出限为2.3μg/L(取样量为0.25 ml),2个浓度尿碘标准物质的测定值均在规定的不确定度范围内，相对标准偏差(RSD)为1.9%～2.8%(n=6)。盐碘方法在含碘量0 mg/L～5.0 mg/L标准曲线范围内吸光度的对数与浓度呈线性，相关系数r绝对值>0.999 0,检出限为0.85 mg/kg(取样量为60μl盐样水溶液),3个浓度盐碘标准物质的测定值均在规定的不确定度范围内，相对标准偏差(RSD)为0.7%～2.6%(n=6)。结论 该方法代替传统的手工法，操作方便快捷，灵敏度、准确度、精密度均符合检测要求。     

茶叶的高精度低氟标准物质的研制

氟是人体必需的微量元素 ,适量的氟有益于人体骨骼和牙齿的发育 ,但长期过量摄入会导致氟中毒。在国内对生物材料氟标准物质的研制中 ,已对高氟茶叶作过定值 [1 ](GBW0 76 0 5 1991年 32 0 μg/ g,不确定度 2 0 % )。美国研制了用于土壤和植物检测质控的标准物质 ,对氟作了定值 (COMARNo:0 30 0 10 5 2 0 SRM2 6 95 / 2 1991年 ,2 77μg/ g,不确定度10 0 % )。本标准物质的氟定值为 6 4.3μg/ g,相对标准差 8.4%。　　　1　材料与方法1.1　标准物质的制备选用含氟量较低的安徽黄山特级绿茶为本标准物质的候选物 ,按国家一级标准物质技…     

调整食盐加碘量前后山东省儿童碘营养状况分析

[目的]分析食盐加碘量调整对学龄儿童碘营养水平的影响。[方法]对食盐加碘量为20~60 mg/kg的1995年、1997年、1999年和食盐加碘量为(35±15)mg/kg的2002年、2005年山东省碘缺乏病监测中儿童碘营养状况进行分析。[结果]食盐加碘量调整前后分别检测尿样1 051份、720份,尿碘中位数分别为269.4μg/L、213.9μg/L,推算的每人每天碘摄入量分别为404.1μg、320.8μg,尿碘<100μg/L者所占比例分别为14.94%、11.53%,尿碘≥300μg/L者所占比例分别为46.52%、27.22%(P<0.01)。盐加碘量调整前后分别调查8~10岁儿童3 668人2、400人,甲状腺肿大率(触诊法)分别为14.53%、5.08%(P<0.01)。[结论]调整食盐加碘量后儿童碘营养状况良好,儿童甲状腺肿大率明显下降。     

宜兴市孕妇和哺乳期妇女碘摄入量调查

目的对食盐加碘剂量作出评估。方法随机检测宜兴市五个乡(镇、街道)孕妇和哺乳期妇女的尿碘排泄量、食盐食用量和24 h排尿量,计算其碘摄入量、加碘食盐供给碘量和环境碘来源。结果 230例调查对象的尿碘排泄量为146μg/L、食盐食用量6.65 g/d和24 h排尿量水平为1.8 L;其碘摄入量、加碘食盐供给碘量和环境碘来源分别为262.8μg/d、154.7μg/d和108.1μg/d。结论宜兴市孕妇和哺乳期妇女碘摄入量高于国际组织新近推荐的碘摄入量200μg/d,碘营养充分。加碘食盐供给碘量在WHO规定的150～300μg/d安全范围之间,国家当前的食盐加碘剂量标准对宜兴市而言是适宜的。     

消毒剂中有效碘标准物质的定值及不确定度评定

目的对所研制的消毒剂中有效碘标准物质进行定值及不确定度评定。方法经均匀性、稳定性试验后,采用多家实验室对标准物质进行定值及不确定度评定,完成合成标准不确定度及扩展不确定度的计算,给出有效碘标准物质的最终特性量值。结果消毒剂中有效碘标准物质的特性量值应表达为(0.508±0.004)%(k=2)。结论有效碘标准物质具有较好的均匀性及稳定性,定值结果符合标准物质要求,可用于消毒剂中有效碘测定的质量控制和能力验证。     

玉米中氟成分标准物质的研制

本文根据目前国内煤烟氟污染监测工作中对质量控制的要求,研制了玉米中氟成分标准物质(两种氟浓度)。该标准物质经均匀性检查证明,样品是均匀的,经稳定性考察稳定期已达一年。采用了三种原理不同的准确、可靠方法(离子色谱法、电极法、比色法)定值。高、低浓度玉米标样的保证值和不确定度分别为33.7±2.2和1.91±0.18μg/g。玉米氟成分标准物质並可代替其它类似生物标准物质使用,本标准物质经有关部门使用反映良好。     

玉米中氟成分标准物质的研制

本文根据目前国内煤烟氟污染监测工作中对质量控制的要求,研制了玉米中氟成分标准物质(两种氟浓度)。该标准物质经均匀性检查证明,样品是均匀的,经稳定性考察稳定期已达一年。采用了三种原理不同的准确、可靠方法(离子色谱法、电极法、比色法)定值。高、低浓度玉米标样的保证值和不确定度分别为33.7±2.2和1.91±0.18μg/g。玉米氟成分标准物质并可代替其它类似生物标准物质使用,本标准物质经有关部门使用反映良好。     

2006~2012年大连市孕妇碘营养水平监测

目的了解大连市孕妇碘营养状况,为碘缺乏病的防治工作提供科学依据。方法 2006~2012年,在全市9个县区中,每县区连续采集至少30个孕妇日间随意尿样,检测尿中碘含量。结果 2 039名孕妇的尿碘中位数为167.20μg/L,2006~2012年尿碘中位数分别为189.60、159.40、174.60、168.20、129.55、177.05、161.50μg/L;孕早期、孕中期和孕晚期尿碘中位数分别为169.20、165.35、168.60μg/L。结论 2006~2012年,全市孕妇碘营养水平总体上达到标准,但接近标准下限,且2010年孕妇碘营养水平较低;各期孕妇碘营养水平没有差异。     

冻干人尿中汞成分分析标准物质的研制

目的 研制冻干人尿中汞成分分析标准物质.方法 冻干尿由正常人尿经过滤、加标、混匀、分装、冷冻干燥、辐射灭菌制备而成,使用原子荧光测定方法 对其均匀性和稳定性进行检验,由3家实验室用准确可靠的方法 确定标准值,并对尿中汞研制物的不确定度进行分析.结果 本研制物均匀性良好,-20 ℃保存可稳定18个月,2个水平的量值及不确定度分别为(35.6±2.1)和(50.5±3.0)μg/L.结论 尿中汞成分分析标准物质各项指标符合<国家一级标准物质研制规范>的要求,可用于实验室检测的质量控制.

Abstract：

Objective To develop the certified reference material of mercury in lyophilized human urine. Methods Human urine samples from normal level mercury districts were filtered, homogenized,dispensed, lyophilized and radio-sterilized. Homogeneity test, stability inspection and certification were conducted using a atom fluorescence spectrophotometric method. The physical and chemical stability of the certified reference material were assessed for 18 months. The certified values are based on analysis made by three independent laboratories. Results The certified values are as follows: low level was (35.6±2.1)μg/L,high level was (50.5±3.0) μg/l. Conclusion The certified reference material of mercury in lyophilized human urine in this research reached the national certified reference material requirements and could be used for the quality control.     

卷烟中镉成分分析标准物质的研制

目的该标准物质的研制对卷烟中镉的分析质量进行准确评价和卷烟中镉指标的安全性评价提供客观、科学的依据。方法根据国家一级标准物质技术规范（JJG 1006-94）的要求进行研制。结果该标准物质采用原子吸收光谱法和等离子发射光谱法2种不同原理分析方法进行定值。按格拉布斯法则判断每组数据，正态性D检验确认6组定值的实验数据为正态分布。标准物质总算术平均值和标准偏差分别为5．1和0．4mg/kg。结论该标准物质研制过程和结果符合国家一级标准物质的要求，申请国家一级标准物质、     

天津市售食品碘含量及部分大学学生碘营养状况的研究

目的了解当前市售食品碘含量,部分大学生膳食碘营养状况,碘盐对膳食摄入碘的补充作用,以及尿碘测定结果对膳食碘的反映程度。方法分层随机采集日常市售食物278份,采用砷铈接触法测定食品碘含量,膳食记录法调查学生的7日膳食情况,砷铈催化分光光度法测定尿碘。结果47种、278份食物样品的检测表明,动物性食品的含碘量（7．8ug／100g～30．8ug／100g）高于植物性食品的含碘量（1．8ug／100g～16．1ug／100g）。膳食调查显示该类学生中以素食为主的占70．19％,以食物碘含量的实测值和膳食调查结果计算出由食物中摄入碘的量为（111．67±53．18）ug/d,而从碘盐中补充碘量（230．27±45．55）ug／d,那么从膳食中共可以摄入碘（341．95±89．58）ug/d。经尿肌酐校正后每克肌酐尿中碘含量中位数为271．28ug／gCr。经尿肌酐校正后的尿含碘量与膳食摄碘量呈正相关关系（0=0．463,P〈0．01）。结论这部分学生多数来自低收入家庭且膳食以素食食物为主,每日从膳食中摄入的碘量低于碘的推荐供给量（RDA）150ug,但是从加碘食盐中可以获得碘230．27ug,从而弥补膳食摄碘量的不足。     

冻干人尿中镉标准物质的研制

目的研制冻干人尿中镉标准物质。方法采集正常人尿经处理后作为基质,通过加标、混匀、分装、冷冻干燥制备而成;经均匀性检验、稳定性考察后,由7家实验室采用2种方法进行合作定值,并进行不确定度评定。结果研制的标准物质最小取样量为0.20 ml,2个水平的均匀性检验值F分别为1.69和1.49,差异无统计学意义(P>0.05)。冻干标准物质在≤4℃下保存可稳定12个月,复溶后的标准物质溶液在4℃条件下可稳定7 d。2个水平的标准量值及不确定度分别为(5.34±0.34)μg/L和(15.47±0.72)μg/L(k=2)。结论研制的标准物质各项指标符合国家相关要求,可用于人尿中镉检测方法验证及相关样品检测。     

不同浓度碘盐对人群碘营养状况影响的现场试验研究

目的观察不同浓度碘盐对人群碘营养状况影响,寻找适合当地居民食用的盐碘浓度。方法采用流行病学的现场群组干预试验研究方法,对南昌市399户城乡居民共1099人,随机分配4个组,分别提供含碘浓度为(6±2)mg/kg、(15±2)mg/kg、(24±2)mg/kg、(34±2)mg/kg的碘盐,并将其家中原有的碘盐换回。采用单盲法进行31天的干预试验。采集受试者干预前及干预后第27- 31天的一次随机尿样检测尿碘浓度,并进行膳食调查,同时采集干预前受试者实际食用碘盐检测碘含量;采集当地水源水样8份,检测水碘含量。结果当地水碘含量中位数3.05μg/L,干预前盐碘浓度为(36.4±5.4)mg/kg,碘盐合格率98.8%;干预前城区居民尿碘中位数为293.6 μg/L,农村居民尿碘中位数为508.8 μg/L。干预后第27、28、29、30、31天各组人群尿碘中位数不同日期之间的差异无统计学意义(P>0.05)。干预后第28天4个干预组的尿碘中位数:城区分别为97.2、198.6、249.4和330.7μg/L,农村分别为100.5、193.0、246.3和308.3 μg/L。结论当地属于缺碘地区,居民普遍食用合格碘盐,尿碘水平偏高;适宜当地居民食用的碘盐含碘浓度为15-25 mg/kg。     

An evaluation of salt intake and iodine nutrition in a rural and urban area of the C?te d'Ivoire.

OBJECTIVE: To evaluate the habitual salt intake of individuals living in the C?te d'Ivoire, and to monitor the iodine nutrition of adults, schoolchildren and pregnant women one year after implementation of a universal salt iodisation programme. DESIGN: A three day weighed food records with estimation of food intake from a shared bowl based on changes on body weight, determination of sodium and iodine concentrations in 24 h (24 h) urine samples from adults, and determination of urinary iodine in spot urines from schoolchildren and pregnant women. SETTING: A large coastal city (Abidjan) and a cluster of inland villages in the northern savannah region of the C?te d'Ivoire. SUBJECTS: For the food records: 188 subjects (children and adults) in the northern villages; for the 24 h urine collections: 52 adults in Abidjan and 51 adults in the northern villages; for the spot urine collections: 110 children and 72 pregnant women in Abidjan and 104 children and 66 pregnant women in the north. MAIN RESULTS: From the food survey data in the north, the total mean salt intake (s.d.) of all age groups and the adults was estimated to be 5.7 g/d (+/- 3.0), and 6.8 g/d (+/- 3.2), respectively. In the 24 h urine samples from adults, the mean sodium excretion was 2.9 g/d (+/- 1.9) in the north and 3.0 g/d (+/- 1.3) in Abidjan, corresponding to an intake of 7.3-7.5 g/d of sodium chloride. In the north the median 24 h urinary iodine excretion in adults was 163 microg/d, and the median urinary iodine in spot urines from children and pregnant women was 263 microg/l and 133 microg/l, respectively. In contrast, in Abidjan the median 24 h urinary iodine was 442 microg/d, with 40% of the subjects excreting > 500 microg/d, and the median urinary iodine in spot urines from children and pregnant women was 488 microg/l and 364 microg/l, respectively. Nearly half of the children in Abidjan and 32% of the pregnant women were excreting > 500 microg/l. CONCLUSION: Based on the estimates of salt intake in this study, an optimal iodine level for salt (at the point of consumption) would be 30 ppm. Therefore the current goals for the iodised salt programme--30-50 ppm iodine appear to be appropriate. However, in adults, children and pregnant women from Abidjan, high urinary iodine levels--levels potentially associated with increased risk of iodine-induced hyperthyroidism--are common. These results suggest an urgent need for improved monitoring and surveillance of the current salt iodisation programme in the C?te d'Ivoire.     

冻干人尿中碘成份分析标准物质的研制

本标准物质由正常人尿和低碘地区人尿通过过滤、混匀、分装、冷冻干燥、辐射灭菌制备而成。用分光光度法进行均匀性和稳定性检验。结果表明，本标准物质均匀性良好，并至少可稳定１年。由５个实验室用３种不同原理的分析方法确定的标准值为：低浓度：（１２１±１４）μｇ／Ｌ，正常浓度为（２０１±１１）μｇ／Ｌ。     

Iodine levels in food and soil in different regions in Cameroon

Iodine deficiency diseases (IDD) are a public health problem in many developing countries, such as Cameroon. They are often the consequence of insufficient iodine intake and/or the effect of thiocyanate in foods such as cassava; this chemical inhibits iodine fixation by the thyroid gland. One method of combatting these diseases is to counsel and encourage the consumptions of iodine-rich foods. We accordingly undertook an evaluation of the iodine content of staple foods, the soil, and the salt in some zones of western Cameroon and in the capital. Food (63), salt (04) and soil (05) samples were collected in four villages of western Cameroon, and food (20), water (18) and salt samples (14) were collected in Yaoundé (central province). Iodine content in foods and soils was assessed by the catalytic destructive testing of thiocyanate by nitrate in the presence of iodine. Iodine content in water was determined colorimetrically after mineralization and in salt by volumetric methods. Results show that iodine levels in salt depend on its origin, but was much lower than the 50-100 ppm recommended by the WHO. Soil and water levels depended on the stream and the origin. Several of the more than 20 foods sampled from Yaoundé had iodine concentrations higher than 10 microg/100 g: plantain (22.5 microg/100 g), wheat flour (21 microg/100 g), corn flour (17.75 microg/100 g), groundnuts (12.5 microg/100 g), sweet potatoes (12.25 microg/100 g), zoom (11.34 microg/100 g) and rice (10.45 microg /100 g). In western villages, we noted that iodine levels in food crops depended on the soil levels. Nevertheless, it was high in cocoyam (79.5 microg/100 g), yarns (68 microg/100 g), potatoes (62 microg/100 g), plantains (58.15 microg/100 g), and red beans (53.93 microg/100 g). In general, these crops contain more iodine than the food in Yaoundé; these results can be used to combat IDD, especially among young children, teenagers and pregnant women.     

Iodine nutrition among indigenous Tarahumara schoolchildren in Mexico

This paper adds iodine data to the nutritional survey recently published in the Eur J Clin Nutr (2004;58:532-540) to identify growth retardation and micronutrient deficiencies among Tarahumara children from five selected indigenous boarding schools in Mexico. Total goiter rate (TGR) (n=384), urinary iodine concentrations (UI) (n = 100), and iodine content of salt were measured. Overall, TGR was 7.0% (grade 1 = 6.8%, grade 2 = 0.2%). The median UI of the group was 125 microg/l, while the median UI across the schools ranged from 92.0-156.5 microg/l, with 32 and 6% of the children having UI between 50-99 microg/l and 20-49 microg/l, respectively. The iodine content in all the salt packages checked at the schools was above 25 parts per million. Based on TGR and UI, there is a marginal iodine deficiency in this sample of children, probably due to an insufficient iodine intake. These results add to existing evidence that iodine deficiency still constitutes a public health problem in certain populations living in the mountainous regions in Mexico.