原子吸收光谱法间接测定生活饮用水中硫酸盐

硫酸盐在自然界中广泛存在，一般地下水及地面水均含有硫酸盐。硫酸盐是生活饮用水水质常规检验项目之一。《生活饮用水卫生规范》中测试方法有硫酸钡灼烧称量法、铬酸钡比色法、硫酸钡比浊法及离子色谱法，且操作繁杂，条件控制要求严格。本文以火焰原子吸收光谱法测定中间钡离子而间接测定水中硫酸盐，具有操作简单、准确度好、精密度高，能满足生活饮用水中硫酸盐的测定要求。     

国强标《生活饮用水用聚氯化铝》报批公示 多项分析方法有变动

<正>3月11日,工业和信息化部科技司发布关于《生活饮用水用聚氯化铝》强制性国家标准报批公示的通知,公示时间:2019年3月11日-2019年4月12日,建议批准发布后6个月实施。内容显示,《生活饮用水用聚氯化铝》(GB 15892—201X)按照GB/T1.1-2009给出的规则起草,规定了生活饮用水用聚氯化铝的要求、试验方法、检验规则、标志、包装、运输和贮存,适用于生活饮用水用聚氯化铝,该产品主要用于生活饮用水的净化。本标准代替G     

生活饮用水中挥发性有害有机污染物分析及其安全性评价

生活饮用水安全性是与人们身体健康休戚相关的问题,除了微生物和重金属外,饮用水中有害有机污染物的存在情况也日益受到人们的关注。从1974年发现氯消毒会产生具有致突变和致癌症的三氯甲烷以来,国际饮用水界研究消毒副产物的工作就没有停止过。大量流行病学研究证明长期饮用氯消毒的水会增加人们得癌症的危险。为此,世界各国和地区都制定了生活饮用水水质标准及规范,以保证人们生活饮用水的安全性。美国《国家饮用水基本规则》对92种污染物做出了硬性规定,世界卫生组织(WHO)则有133项,其中有机物占89项,欧共体有61项,我国卫生部2001年颁布的生活饮用水卫生规范有96项,其中常规检验指标有34项,增加了一些消毒副产物的规定,虽然大部分为非常规项目,但有了相关限定值。本文对有代表性的几种生活饮用水中挥发性有机物进行了分析测定。     

原子荧光光谱法测定水中汞含量的不确定度评定

汞是我国生活饮用水卫生标准中的毒理学指标,原子荧光光谱法是测定水中汞的方法之一.按照ISO/IEC17025-2005《检测和校准实验室能力的通用要求》的规定[1],检测实验室应对测量(检测)结果给出不确定度评定.本文根据JJF1059-1999技术规范的要求[2],对原子荧光光谱法测定汞含量的测量不确定度进行分析,获得不确定度评定结果.     

城市饮用水安全保障体系2020年建立

不久前,国家发展改革委、水利部、建设部、卫生部、国家环保总局编制的《全国城市饮用水安全保障规划（2006—2020）》印发。按照《规划》目标,到2020年,将建立起比较完善的饮用水安全保障体系,满足2020年全面实现小康社会目标对饮用水安全的要求。“十一五”期问,重点解决205个城市及350个问题突出的县级城镇饮用水安全问题。     

环保部印发新国标 饮用水水源保护区划分技术更加规范

正为贯彻《中华人民共和国环境保护法》、《中华人民共和国水污染防治法》,加强集中式饮用水水源地环境保护和治理、防范饮用水水源污染风险,保障饮用水安全,近日,环保部印发了《饮用水水源保护区划分技术规范》(HJ 338-2018)。本标准规定了地表水饮用水水源保护区、地下水饮用水水源保护区划分基本方法、定界、饮用水     

挥发性卤代烃标准液配制的探讨

挥发性卤代烃通常指沸点在200℃以下的卤代烃化合物。由于近年地表水源水的污染日趋严重，导致了饮用水中卤代烃含量升高。所以在我国卫生部颁布的《生活饮用水卫生规范》对多种卤代烃的含量规定一定的限值。     

电感耦合等离子体质谱法测定生活饮用水中钡的不确定度评定

评定电感耦合等离子体质谱（ICP-MS）法测定生活饮用水中钡含量的不确定度。根据JJF 1059.1—2012《测量不确定度评定与表示》对各个不确定度来源（包括采样、样品保存、系列标准溶液的配制、校准曲线拟合和测量重复性）进行分析和量化，获得扩展不确定度。生活饮用水中钡的扩展不确定度为2.9μg/L，钡的测量结果为（50.3±2.9）μg/L。结果表明，方法的不确定度主要来源于系列标准溶液配制过程。     

泉州具备检测城市供水新标准能力

不久前,从泉州召开的全省城市供水水质新标准培训会议上获悉,泉州有望具备检测城市供水新标准全部106项指标的能力,市民用水将更有保证。根据2005年建设部出台的《城市供水水质标准》要求,居民饮用水有100多个检测指标把关,达不到强制性标准的水将禁止居民饮用。泉州正紧抓落实,逐步开展106项水质指标的检测,泉州市水质监测站拟于2009年底,具备新标准要求的全部106项的检测能力。(志)泉州具备检测城市供水新标准能力@志     

饮用水中环氧氯丙烷分析方法的研究

通过比较分析饮用水中环氧氯丙烷的多种方法后,确定了以HP-FFAP毛细管色谱柱-固相萃取-FID气相色谱法测定水中环氧氯丙烷,该方法线性关系良好,灵敏度高,通过优化条件,方法的最低检出浓度为0.00025 mg/L,满足《生活饮用水卫生标准》(GB5749-2006)的要求以及实际水质检测的需求。     

微量元素与防癌保健饮水器

简述了微量元素与人体健康的关系。人体主要是吸收周围环境溶解在水中的微量元素．各地区的环境差异造成微量元素的不平衡.为此介绍了以长寿地区饮用水为标准的改水器具——防癌保健饮水器．     

Bitterness evaluation of medicines for pediatric use by a taste sensor

The purpose of this study was to evaluate the bitterness of 18 different antibiotic and antiviral drug formulations, widely used to treat infectious diseases in children and infants, in human gustatory sensation tests and using an artificial taste sensor. Seven of the formulations were found to have a bitterness intensity exceeding 1.0 in gustatory sensation tests (evaluated against quinine as a standard) and were therefore assumed to have an unpleasant taste to children. The bitterness intensity scores of the medicines were examined using suspensions in water or an acidic sports drink. In the case of three macrolide antibiotic formulations containing erythromycin (ERYTHROCIN dry syrup), clarithromycin (CLARITH dry syrup for pediatric), and azithromycin (ZITHROMAC fine granules for pediatric use), the bitterness intensities of suspensions in acidic sports drinks were dramatically enhanced compared with the corresponding scores of suspensions in water. This enhancement could be predicted using the taste sensor. On the other hand, a reduction of bitterness intensity was observed for an acidic sports drink suspension of an amantadine product (SYMMETREL fine granules) compared with an aqueous suspension. This reduction in bitterness could also be predicted using the taste sensor output value. Thus, the taste sensor could predict whether or not suspension in an acidic sports drink would enhance or reduce the bitterness intensity of pediatric drug formulations, compared with suspensions in water.     

The Effect of Coconut Water (Cocos Nucifera L.) and an Isotonic Drink on the Change of Heart Rate Frequency in the Rats Induced Hypertension

The objective of the present study was to evaluate the effect of coconut water (Cocos nucifera L) and an isotonic drink on the changes of heart rate frequency in the rats induced hypertension. Wistar male rats were divided into five groups: a negative group, a mineral-watered group, a coconut-watered group, a group with isotonic drink, and a group with medicine. The rats were induced hypertension by administering NaCl solution high concentration for 14 days, and then they were treated with the test materials given to each group for another 14 days without stopping the induction. Their heart rate was measured using a tail cuff before the induction (d0), at the beginning of the treatment (d14), and at the end of the treatment (d28). When being induced hypertension, higher heart rate frequency was significantly showed by the groups with coconut water and isotonic drink (p<0.05) compared with the control group. When the rats of coconut water group were treated with coconut water, their heart rate became significantly lower (p<0.05) compared to the control groups. When the rats of isotonic drink group were treated with isotonic drink, their heart rate was lower, although not significant, than the control groups. The results showed that coconut water (C. nucifera L) lowered the heart rate frequency better than the isotonic drink.     

Method validation for direct determination of some trace and toxic elements in soft drinks by inductively coupled plasma mass spectrometry

The consumption of soft drink beverages has increased in the last few years around the world and it is related to the diversity of brands and flavours available, increasing also the risk of ingestion of compounds considered non-beneficial to the health of consumers. In this study, fast, easy and simple method of analysis for direct determination of As, Pb, Cd, Sb, Hg, Cu, Zn, Fe, Al, Cr, Sn, Co, Mn and Ni in soft drink samples using quadrupole inductively coupled plasma mass spectrometry (Q-ICP–MS) was validated. The estimated detection limits, practical quantification limits, linearity (linear dynamic ranges and method linearity), accuracy (trueness and precision) and measurement uncertainty parameters were studied under optimised (Q-ICP–MS) conditions. The method showed that the estimated detection limits were varied between 0.02 and 2.403 µg/L, and the quantification limits were varied between 0.5 and 20 µg/L. The mean recoveries ± standard deviations at different spiking levels were varied between 75.03 ± 0.62% and 117.07 ± 2.83% and the coefficients of variation were varied between 0.49% and 9.79%. The method trueness was confirmed by using four different certified reference materials (soft drinks and treated water) purchased from FAPAS (Food Analysis Performance Assessment Scheme) and all obtained results were within satisfactory ranges and had acceptable recovery and Z-score values. The method precision, in terms of relative standard deviation, was below 4.88%. The method uncertainty expressed as expanded uncertainty of all validated elements was found to be ≤22.52%. The results obtained make the method suitable for accurate determination of validated elements in different kinds of soft drink samples at these low concentration values. Validated method was used for the determination of metallic contaminants in 40 commercial soft drink samples and the results were compared with the provisional guideline of the elements stated by Egyptian, WHO and European standards in drinking and potable bottled natural mineral water.     

纳米固相微萃取应用于干红辣椒、水果饮料及红酒中罗丹明B的定量分析

制备了一种新型的聚苯乙烯纳米纤维, 将其作为固相萃取吸附剂装填制成固相萃取柱, 与高效液相色谱联用建立了干辣椒、 水果饮料及红酒中罗丹明B的定量分析方法. 高效液相色谱以3 g/L磷酸缓冲液-甲醇混合溶液(体积比3∶7, pH=7.0)为流动相. 通过对提取条件的优化, 得到该方法对干辣椒中罗丹明B的检出限为0.1 ng/g, 最低定量限为0.6 ng/g; 对水果饮料和红酒中罗丹明B的检出限均为0.2 ng/mL, 最低定量限均为0.5 ng/mL. 此方法对干辣椒中罗丹明B的提取回收率为98.2%~110.3%; 对水果饮料中罗丹明B的提取回收率为94.6%~102.2%; 对红酒中罗丹明B的提取回收率为90.4%~104.6%. 该方法的线性范围为1~100 ng/mL(ng/g), 相对标准偏差为2.3%~9.0%. 该方法灵敏度高、 选择性好, 可用于干辣椒、 水果饮料及红酒中罗丹明B的定量分析.     

液相色谱-串联质谱法快速测定饮用水中6种雌激素

建立了液相色谱-质谱法测定饮用水中17-β-雌二醇、17-α-雌二醇、17-α-乙炔雌二醇、己烷雌酚(HEX)、己烯雌酚(DES)和双烯雌酚(DE)6种雌激素的分析方法.样品经乙腈萃取,Oasis HLB柱富集净化后,采用液相色谱-质谱法测定.方法在5～100 μg/L范围内呈良好线性,相关系数为0.994～1.000...     

Identifying Chemical Composition,Safety and Bioactivity of Thai Rice Grass Extract Drink in Cells and Animals

Rice grass has been reported to contain bioactive compounds that possess antioxidant and free-radical scavenging activities. We aimed to assess rice grass extract (RGE) drink by determining catechin content, free-radical scavenging and iron-binding properties, as well as toxicity in cells and animals. Young rice grass (Sukhothai-1 strain) was dried, extracted with hot water and lyophilized in a vacuum chamber. The resulting extract was reconstituted with deionized water (260 mg/40 mL) and served as Sukhothai-1 rice grass extract drink (ST1-RGE). HPLC results revealed at least eight phenolic compounds, for which the major catechins were catechin, epicatechin and epigallocatechin-3-gallate (EGCG) (2.71–3.57, 0.98–1.85 and 25.47–27.55 mg/40 mL serving, respectively). Elements (As, Cu, Pb, Sn and Zn) and aflatoxin (B1, B2, G1 and G2) contents did not exceed the relevant limits when compared with WHO guideline values. Importantly, ST1-RGE drink exerted radical-scavenging, iron-chelating and anti-lipid peroxidation properties in aqueous and biological environments in a concentration-dependent manner. The drink was not toxic to cells and animals. Thus, Sukhothai-1 rice grass product is an edible drink that is rich in catechins, particularly EGCG, and exhibited antioxidant, free radical scavenging and iron-binding/chelating properties. The product represents a functional drink that is capable of alleviating conditions of oxidative stress and iron overload.     

Sample preparation and determination of ginkgo terpene trilactones in selected beverage, snack, and dietary supplement products by liquid chromatography with evaporative light-scattering detection

Ginkgo biloba leaf extract has been widely used in dietary supplements and more recently in some foods and beverages. Sample preparation procedures for determination of ginkgo terpene trilactones (including bilobalide and ginkgolides A, B, C, and J) in various sample matrixes were developed in this study. Ginkgo leaves and capsules were extracted with 5% KH2PO4 aqueous solution under sonication. Tea bags were extracted with boiling water, whereas drink samples were taken directly from the bottles. After filtration and the addition of NaCl to approximately 30% (w/v), the terpene trilactones in aqueous solutions were quantitatively extracted with ethyl acetate-tetrahydrofuran (4 + 1, v/v). Puff samples (a cereal-based fried snack item) were first defatted by using hexane or by using supercritical fluid extraction and then extracting under sonication with methanol-acetic acid (99 + 1, v/v). After evaporation of the organic phase, the terpene trilactones were redissolved in methanol and determined on a C18 reversed-phase column by liquid chromatography (LC) with evaporative light-scattering detection. The method of standard additions and gas chromatography with flame ionization detection were used for method validation. For most samples, the relative standard deviation was <10%. The identities of target compounds in ginkgo leaves and drink samples were confirmed by LC/electrospray ionization-tandem mass spectrometry.     

An untargeted metabolomics approach to contaminant analysis: pinpointing potential unknown compounds

This study deals with an automated data analysis strategy to pinpoint potential unknown compounds in full scan mass spectrometry (MS) experiments. Three examples of an untargeted metabolomics approach to contaminant analysis are given. By comparing a plant-oil based hormone cocktail to 90 plant oil samples ca. 25 compounds specific to the hormone cocktail could be detected. Five of these compounds were confirmed as steroid hormones. A comparison of a drink water sample from a farm to distillated water showed the presence of contaminants specific to this drink water sample. A grass sample, which was known to give a false positive result in a DR-CALUX bioassay, was unexpectedly shown to contain an abnormal level of chrysene, which was obviously not eliminated during clean-up.     

Dehydrierung: Die Angst geht um

Water is healthy, even vital, but can also be toxic. An effective biochemical control system in our bodies takes care of our optimal daily water intake. We don't have to worry about becoming dehydrated under normal circumstances, if we drink when we're thirsty and stop if we're not. We only go into danger if we force ourselves to exorbitantly drink a lot of water and don't listen to our bodies. Blessed is he who knows a little general chemistry, coupled with common sense and some critical distance towards the much proclaimed but often unqualified Zeitgeist and fad diets.