苯暴露大鼠尿中反-反式黏糠酸变化研究

目的观察苯动态染毒大鼠模型尿中反-反式黏糠酸(t,t-MA)的变化情况,探讨尿t,t-MA作为苯职业暴露水平生物标志物的可行性。方法48只成年Wistar大鼠,随机分为对照组、低浓度组、中浓度组和高浓度组,每组数量相同,雌雄各半;纯苯动态染毒28d(分4个时段,每时段染毒5d后停2d)。监测苯浓度,每个时段染毒后立即取5h尿,反相高效液相色谱-紫外检测法检测大鼠尿中t,t-MA浓度,并用尿肌酐校正。结果在不同染毒时段内,对照组、低、中、高浓度组间尿t,t-MA含量差异有统计学意义(P<0.05),鼠尿中t,t-MA浓度随着环境中苯浓度增高而升高,且没有随染毒时间延长而变化(P>0.05)。结论动物模型研究说明尿中t,t-MA是反映苯接触水平比较敏感的生物标志物。     

职业接触苯工人尿中黏糠酸测定方法与生物限值研究

目的推荐我国职业接触苯尿中反-反式黏糠酸（uMA）生物限值并建立相应的高效液相色谱（HPLC）测定方法。方法选择职业苯接触者56人和非苯接触者24人，应用活性炭吸附管采集工人呼吸带空气、CS2洗脱、毛细管气相色谱法检测个体外暴露水平，同时采集当日工作班前和班末尿样本，应用HPLC测定尿中uMA以观察内暴露水平。尿样经2mol／L盐酸酸化、香草酸为内标、乙酸乙酯萃取预处理，采用ODS柱、冰乙酸：四氢呋喃：甲醇：水（体积比1：2：10：87）为流动相、流速0．9ml／min、紫外检验波长264nm、柱温25℃的色谱条件分离测定尿中uMA。结果uMA的线性范围为0．10～10．00mg／L，检出限为0．10mg／L，加标平均回收率为95．1％～100．5％，批内、批间精密度变异系数分别为4．4％～7．5％和6．2％～8．8％。接苯工人空气苯浓度范围0．332～146．000mg／m^3，平均浓度41．8mg／m^3，班末尿uMA与个体苯接触量存在良好线性关系y（mg／gCr）=2．103＋0．177x（mg／m^3），r=0．791，P〈0．01，将我国职业苯接触限值PC—TWA=6mg／m^3代入回归方程，推算工作班末尿中uMA含量为3．165mg／gCr。结论建立的HPLC测定uMA方法简便、快速、灵敏，可用于职业接触苯的生物监测，参考国内外文献和国外相关标准，建议我国职业接触苯生物限值班末尿uMA为2．4mmol／molCr（3．0mg／gCr）。     

苯接触与尿中反-反式黏糠酸和苯巯基尿酸关系研究

目的探讨职业苯接触与尿中反-反式黏糠酸(ttMA)和苯巯基尿酸(SPMA)的相关性,评定两接触标志物作为生物监测指标的适用性。方法对44名制鞋厂接苯工人进行个体苯暴露水平的作业环境监测,采集当日班前与班后尿样,分别用高效液相色谱和液质联谱测定尿中ttMA和SPMA含量。结果个体苯接触浓度为2.57~146.11 mg/m3,几何平均浓度为(27.91±3.29)mg/m3。班后尿中ttMA和SPMA含量均较班前增高,差异有统计学意义(P0.01),班后ttMA和SPMA与空气苯浓度的相关系数分别为0.905(P0.01)和0.537(P0.01),个体苯接触代谢转化为ttMA和SPMA的相对内暴露指数(RIE)随苯接触浓度的增高而下降。结论在中、高浓度的苯接触时,班后尿ttMA与空气苯浓度的相关性优于SPMA。     

苯暴露者尿中反，反－粘康酸高效液相色谱检测法的建立及应用

本研究应用特异、敏感的高效液相色谱法，在紫外吸收波长２６５ｎｍ时，检测苯的代谢物，尿中的反，反－粘康酸（ｔｔＭＡ）。１ｍｌ尿液与２ｍｌ含香草酸作内标的Ｔｒｉｓ缓冲液混合，通过经预处理的阴离子交换柱。经磷酸、醋酸钠及去离子水洗涤，ｔｔＭＡ最后用１．５ｍｏｌ／Ｌ氯化钠－甲溶液洗脱。流动相为５ｍｏｌ／Ｌ醋酸钠含１％（Ｖ／Ｖ）醋酸和１２％甲醇（Ｖ／Ｖ）。流速为ｌｍｌ／ｍｉｎ，至第６ｍｉｎ时流速为１．５ｍｌ／ｍｉｎ。ｔｔＭＡ和内标ＶＡ分别在６．８和１２．８ｍｉｎ检出。本实验ｔｔＭＡ最低检出量为０．０５ｍｇ，回收率在９０％以上。现场应用结果提示，尿液ｔｔＭＡ可作为苯暴露者的生物监测指标。     

工作场所空气中尿素的高效液相色谱检测法

目的 建立工作场所空气中尿素的高效液相色谱检测法.方法 以纯水为流动相,流速0.95 ml/min,选用C18色谱柱,检测波长190 nm,高效液相色谱法测定.结果 尿素在0～300μg/ml范围内线性关系良好,相关系数为0.9996,方法检出限为0.4 μg/ml,低、中、高浓度尿素溶液精密度分别为3.1%、2.5%和3.7%.以玻璃纤维滤膜为采样滤料,采样效率为93.0%～98.0%.采集样品存放于具塞比色管中,可保存7 d以上.结论 该方法操作简便,精密度和灵敏度较高,可以满足工作场所空气中尿素的测定.     

职业苯接触生物标志物反-反式粘糠酸的分析与评价

反-反式粘糠酸(ttMA)作为职业苯接触的生物标志物，在低浓度苯接触条件下与苯接触水平呈线性相关，ttMA在机体内的代谢转化速率与苯接触水平、甲苯的联合暴露、防腐剂山梨酸的摄入、吸烟以及遗传因素存在一定联系。高效液相色谱固相萃取和毛细管气相色谱是目前测定尿中ttMA较为成熟的检测技术。本文对近年来尿中ttMA的生物监测方法、色谱分析特点及其影响因素作一综述。     

尿中多种多环芳烃代谢物同时测定的高效液相色谱-荧光检测法

目的建立同时测定人尿中多种多环芳烃代谢物(PAHm)的高效液相色谱分析法.方法尿样经过酶解、固相萃取(SPE)法纯化、富集以及氮吹浓缩,然后采用高效液相色谱-荧光检测器检测尿中5种多环芳烃代谢物(PAHm):2-羟基萘、2-羟基芴、9-羟基菲、1-羟基芘以及3-羟基苯并(a)芘.结果2-羟基萘、2-羟基芴、9-羟基菲、1-羟基芘、3-羟基苯并(a)芘的检测限分别为1.65×10-3、0.550、0.084、0.032、0.132μg/L,线性范围分别为0.099～74.000、0.900～680.000、0.63～470.00、1.3～940.0、1.7～1200.0μg/L.回收率为29.41%～132.11%.日内RSD为1.01%～6.27%,日间RSD为2.23%～11.90%.结论该方法可同时检测尿中2-羟基萘、2-羟基芴、9-羟基菲、1-羟基芘、3-羟基苯并(a)芘,灵敏度、精密度高,重复性、回收率良好,可用于PAHs在人体内暴露的生物监测.     

尿中苯巯基尿酸高效液相色谱法测定

苯巯基尿酸(S-pheny lmercapturic acid,S-PMA)是苯的代谢产物之一,经尿液排出量占吸收苯剂量的0.005%～0.3%,其半减期为(9.1±0.7)h^〔1-2〕。在职业与环境低水平苯暴露时,尿中S-PMA与吸入苯浓度之间具有较好相关性,其特异性在于尚未有其他化学物或食物有类似代谢产物^〔1〕。     

苯暴露者尿中反,反—粘康酸高效液相色谱检测法的建立及…

本研究应用特异、敏感的高效液相色谱法，在紫外吸收波长２６５ｎｍ时，检测苯的代谢物，尿中的反，反－粘康酸。１ｍｌ尿液与２ｍｌ含香草酸作内标的Ｔｒｉｓ缓冲液混合，通过经预处理的阴离子交换柱。     

啤酒中玉米赤霉烯酮的高效液相色谱紫外检测法

目的 建立啤酒中玉米赤霉烯酮的高效液相色谱紫外检测法。方法 啤酒中的玉米赤霉烯酮用乙酸乙酯提取,50℃水浴中氮气吹干,用乙腈溶解,过滤,以Zorbax SB-18为分离柱,用甲醇+0.020 mol/L乙酸铵(75+25)溶液为流动相,检测波长236nm。结果 玉米赤霉烯酮在0 μg/ml～10.0 μg/ml范围内,线性关系良好(r=0.999 97);方法检出限5.0μg /kg。方法相对标准偏差(RSD)为2.3%～2.7%,加标回收率为86.0%～100.0%,平均回收率为93.6%。啤酒样品中玉米赤霉稀酮含量为51.6μg/kg～584.0μg/kg。结论 本法具有简便、经济、灵敏、准确的特点,适宜在基层检测机构推广使用。     

职业性苯暴露反-反式粘糠酸生物接触限值研究

目的研究职业性苯暴露反．反式粘糠酸（t,t—MA）生物接触限值。方法实验室建立生产环境空气中苯浓度的气相色谱检测方法及作业工人尿中t,t—MA含量的高效液相色谱检测方法,并通过检测苯暴露现场工人8h苯暴露水平及班前、班后尿中t,t．MA含量,研究其相关性。结果苯暴露者班前、班后尿中t,t—MA含量与其苯暴露水平有明显的相关关系。班前y（mg／gCr）=0．924＋0．108X（me／m^3）,r=0．62,P〈0．01;班后y（mg／gCr）=2．103＋0．177X（mg／m^3）,r=0．791,P〈0．01。结论根据我国作业场所空气中苯的国家卫生标准,按回归方程推导出职业接触苯生物接触限值,推荐职业暴露苯的生物接触限值为工作班班后尿t,t．MA含量为3．0mg／gCr,下一班班前尿t,t．MA含量为1．5mg／gGr。     

改良的高效液相色谱法测定尿中1-羟基芘

改进并规范了尿中 1 羟基芘的碱水解 -高效液相色谱分析方法。尿样经碱水解、二氯甲烷提取后 ,用反相柱分离 ,荧光检测器检测。内标标准曲线法定量。标准曲线线性范围 10～ 50 0 μg L。尿样加标的检出限 (三倍噪声 )为 0 0 1ng ,定量限为 1 0 μg L尿。高、低两个浓度下的回收率分别为 99 5%和 94 0 % ;天内精密度为 5 8%和 6 2 % (RSD) ;天间精密度为 7 7%和 8 9% (RSD)。该方法可用于测定接触多环芳烃人群的尿中 1 羟基芘 ,具有快速简便、准确可靠的特点     

Assessment of urinary trans, trans-muconic acid as a biomarker of exposure to benzene

OBJECTIVE: To assess the use of trans, trans-muconic acid as a biomarker of occupational exposure to benzene. METHODS: Trans, trans-muconic acid in urine samples of exposed (exposed group, n=36) and non-exposed (non-exposed group, n=116) workers to benzene. Urinary levels of trans, trans-muconic acid were quantified by high-performance liquid chromatography. The study sample consisted of subjects exposed to benzene in an oil refinery in Belo Horizonte, Brazil. Non-parametric statistical analysis was carried out using Kruskall-Wallis test, Mann-Whitney test and Spearman correlation at p<0.05. RESULTS: Workers were exposed on average to benzene levels of 0.15 +/- 0.05 mg/m3 (0.05 ppm) and they showed a urinary trans, trans-muconic acid mean value of 0.19 +/- 0.04 mg/g of creatinine. The reference value range of trans, trans-muconic acid in non-exposed subjects was 0.03 to 0.26 mg/g of creatinine (mean 0.10 +/- 0.08 mg/g of creatinine). There was seen a statistical difference between trans, trans-muconic acid levels in urine samples from exposed and non-exposed groups. There was no correlation between urinary trans, trans-muconic acid and air benzene levels. There was no correlation between urinary trans, trans-muconic acid levels in the exposed group and smoking. Alcohol consumption up to 48 hours before sampling procedure showed no effect on trans, trans-muconic acid levels in both exposed and non-exposed groups. There was however a correlation between age (range 18 to 25 years) and urinary metabolite levels in the latter group. CONCLUSIONS: The results show that it is important to evaluate the effect of age and smoking habits on urinary trans, trans-muconic acid levels.     

Improved high performance liquid chromatography determination of hippuric acid and methylhippuric acid isomers in urine

A study was made on the effect of detection wavelength and separation mode of HPLC on determination of urinary hippuric acid (HA) and three isomers of methylhippuric acid (MHA). The interference of other constituents of urine in the determination was effectively decreased by detection at a short wavelength of 227.6 nm. Meta and para MHAs were separated by the addition of beta-cyclodextrine to the mobile phase. Four metabolites were successfully separated from other components of urine by the combination of ODS-silica packed-column and mobile phase (method F). The detection limits were found to be 50 and 5 mg/l for HA and MHAs, respectively. MHAs could not be detected in the non-exposed subjects. Average levels (+/- SD) of HA in non-exposed males and females were 272.2 (+/- 210.8) and 393.0 (+/- 269.8) mg/l, respectively. The urinary levels of HA in females were significantly higher than those in males.     

小微粒色谱柱-高效液相色谱紫外检测器法测定花生中黄曲霉毒素

目的:建立用小微粒色谱柱-高效液相色谱法来测定花生中黄曲霉毒素的方法。方法:样品打碎均匀后,用Bond Elut PH柱萃取,以V水∶V甲醇∶V乙腈=50∶40∶10为流动相,经小微粒色谱柱分离,紫外检测器检测。结果:四种黄曲霉毒素G2、G1、B2、B1得到很好的分离.检测限分别为:0.5μg/kg0、.8μg/kg、0.2μg/kg、0.4μg/kg。花生样品中黄曲霉毒素G2、G1、B2、B1在添加浓度为0.3μg/kg～3μg/kg的范围内,平均回收率在:82%～96%。相对标准偏差在1.2%～3.3%。结论:该法能在短时间内使花生中黄曲霉毒素G2、G1、B2、B1得到很好的分离,准确,比国标法快捷,值得推广。     

Biological monitoring of exposure to benzene: a comparison between S-phenylmercapturic acid, trans,trans-muconic acid, and phenol.

OBJECTIVES--Comparison of the suitability of two minor urinary metabolites of benzene, trans,trans-muconic acid (tt-MA) and S-phenylmercapturic acid (S-PMA), as biomarkers for low levels of benzene exposure. METHODS--The sensitivity of analytical methods of measuring tt-MA and S-PMA were improved and applied to 434 urine samples collected from 188 workers in 12 studies in different petrochemical industries and from 52 control workers with no occupational exposure to benzene. In nine studies airborne benzene concentrations were assessed by personal air monitoring. RESULTS--Strong correlations were found between tt-MA and S-PMA concentrations in samples from the end of the shift and between either of these variables and airborne benzene concentrations. It was calculated that exposure to 1 ppm (8 hour time weighted average (TWA)) benzene leads to an average concentration of 1.7 mg tt-MA and 47 micrograms S-PMA/g creatinine in samples from the end of the shift. It was estimated that, on average, 3.9% (range 1.9%-7.3%) of an inhaled dose of benzene was excreted as tt-MA with an apparent elimination half life of 5.0 (SD 2.3) hours and 0.11% (range 0.05%-0.26%) as S-PMA with a half life of 9.1 (SD 3.7) hours. The mean urinary S-PMA in 14 moderate smokers and 38 non-smokers was 3.61 and 1.99 micrograms/g creatinine, respectively and the mean urinary tt-MA was 0.058 and 0.037 mg/g creatinine, respectively. S-PMA proved to be more specific and more sensitive (P = 0.030, Fisher's exact test) than tt-MA. S-PMA, but not tt-MA, was always detectable in the urine of smokers who were not occupationally exposed. S-PMA was also detectable in 20 of the 38 non-smokers from the control group whereas tt-MA was detectable in only nine of these samples. The inferior specificity of tt-MA is due to relatively high background values (up to 0.71 mg/g creatinine in this study) that may be found in non-occupationally exposed people. CONCLUSIONS--Although both tt-MA and S-PMA are sensitive biomarkers, only S-PMA allows reliable determination of benzene exposures down to 0.3 ppm (8 h TWA) due to its superior specificity. Because it has a longer elimination half life S-PMA is also a more reliable biomarker than tt-MA for benzene exposures during 12 hour shifts. For biological monitoring of exposure to benzene concentrations higher than 1 ppm (8 h TWA) tt-MA is also suitable and may even be preferred due to its greater ease of measurement.     

高效液相色谱法同时测定泡椒凤爪中的苯甲酸和山梨酸

目的:建立同时测定泡椒凤爪中的苯甲酸、山梨酸的高效液相色谱(HPLC)分析方法。方法:样品经搅碎、碱水超声提取、甲醇沉淀蛋白、过滤后进样测定。色谱条件:色谱柱为dC18柱(5μm,4.6×150 mm),流动相为甲醇-乙酸铵(0.02 mol/L)(20∶80);流速为1 ml/min;柱温为40℃;检测波长为254 nm。结果:苯甲酸、山梨酸在0 mg/ml～0.10 mg/ml浓度范围内,线性关系良好,相关系数(r)分别为0.9992和0.9994;苯甲酸的相对标准差(RSD)为0.82%～5.5%、山梨酸为0.57%～4.0%;苯甲酸的加标回收率为92.0%～99.6%,山梨酸为91.3%～104.0%。结论:本方法快速、准确,可有效消除干扰,精密度、准确性均满足检测要求,适合于泡椒凤爪中苯甲酸和山梨酸的同时测定。     

面粉中维生素B1和B2高效液相色谱测定的样品前处理方法优化

目的 优化面粉中维生素B1（VB1）和维生素B2（VB2）测定的样品前处理方法 。方法 以0.1 mol/L盐酸为提取液,样品提取液经中和、酶解、定容过滤后得VB2待测液,VB2待测液经铁氰化钾衍生,正丁醇萃取后得VB1待测液,分别取0.5 mlVB2和VB1待测液用甲醇定容得进样溶液,采用 Waters symmetry C18色谱柱( 4. 6 mm×250 mm,5.0 μm) 分离,荧光检测器检测。结果 VB1和VB2的定量限分别为0.003 mg/100 g和0.006 mg/100 g。VB1在0.025～0.4 μg /ml范围内,线性关系良好( r = 0.9989) ,VB2在0.001 ～ 0.1 μg /ml 范围内,线性关系良好( r = 0.9996) ,3 个添加水平的回收率VB1在83.9% ~ 91.2%之间,VB2在78.9% ~ 87.3%之间,相对标准偏差 RSD 均＜4.9%。结论 该方法前处理简单,准确度高,适用于面粉中VB1和VB2的同时测定。     

高效液相色谱法测定熟食中山梨酸

目的:选择一种前处理简单、操作简便、灵敏度高、重现性好的熟食中山梨酸的检测方法。方法:采用反相色谱法测定熟食的山梨酸含量,醋酸锌和亚铁氰化钾溶液作为沉淀剂,Agilent Ec lipse XDB-C18柱(5μm,4.6 mm×250 mm)液相色谱柱分离,乙酸铵缓冲溶液(0.02 mol/ml)-甲醇(体积比95:5)作为流动相,二级管阵列为检测器进行检测。结果:样品加标回收率为87.2%~92.2%;山梨酸检测限为0.0020 g/ml。结论:该方法具有简便、快速、准确等优点,可用于熟食中防腐剂的检测。     

Evaluation of passive smoking by measuring urinary trans, trans-muconic acid and exhaled carbon monoxide levels

No method has yet been established to evaluate the exposure to tobacco smoke in passive smoking (PS). We therefore conducted a study on the possibility that the levels of urinary trans, trans-muconic acid (MA) and the exhaled carbon monoxide (CO) could be indices of the passive exposure to tobacco smoke. The moderate correlation was observed between urinary MA levels and the number of consumed cigarettes per day in smokers. The mean urinary MA level of the PS (+) group was significantly higher than that with the PS (-) group. Among the PS (+) group, the mean MA level in the urine obtained in the afternoon was higher than that obtained in the morning. A high correlation was observed between the exhaled CO levels and the number of consumed cigarettes per day in smokers. Like the urinary MA level, the mean exhaled CO level in the PS (+) group, too, gave a significantly higher level than in the PS (-) group. Because the biological half life of MA (7.5 +/- 0.85 h) was longer than that of CO (3.0 +/- 0.36 h), the measurement of urinary MA level is recommended for evaluating the exposure of passive smoking. The measurement of exhaled CO levels is useful only for chain smokers and nonsmokers with PS just before measurement.