Objective To investigate the levels of blood lead and zinc protoporphyrin(ZPP),urine lead and δ-aminolevulinic acid(δ-ALA),and the fingerprint characteristics of stable lead isotopes among workers exposed to lead,and to analyze their correlations to provide a foundation for studies and applications of lead stable isotope tracing.Methods Taking 40 lead-exposed workers in a lead-acid battery factory in a city as the research object,the relevant conditions such as working age,smoking,drinking,etc.were recorded by a questionnaire.The levels of blood lead,urine lead,and biomarkers associated with lead exposure were measured,as were the lead isotope ratio(LIR)(207/206Pb,208/206Pb,204/206Pb)in blood,urine,environmental samples(workplace dustfall),and water,and statistical analysis was carried out.Results The blood lead level of the subjects was 56.0-757.6 µg/L,with an average of(300.0±159.8)µg/L,and the abnormality rate of 5.0％;the urine lead level was 2.5-235.3 μg/L,with an average of(40.1±45.2)µg/L,and an abnormality rate of 7.5％;the blood ZPP level was 0.13-7.35 μmol/L,with an average of(1.78±1.86)μmol/L,and an abnormality rate of 17.5％;the urine 8-ALA level was 0.71-7.46 mg/L,with an average of(2.78±1.70)mg/L,and an abnormality rate of 7.5％.Pearson correlation analysis showed positive correlations between overall blood lead and blood ZPP,urine lead and urine 8-ALA,and blood lead and urine 8-ALA(r=0.536,0.728,0.511,P＜0.01).Significant statistical differences were found in blood lead and blood ZPP levels among workers with different employment times(P＜0.05),with the higher levels observed in workers with employment times of 1-4 years;non-drinking workers had higher blood ZPP levels than drinking workers(P＜0.05).Workers exposed to lead had higher levels of 208/206Pb and 207/206Pb in their urine than in their blood(P＜0.01).The tap water from the plant showed lower levels of 208/206Pb and 207/206Pb compared to blood and urine(P＜0.01);the workplace dustfall had a lower level of 208/206Pb compared to blood(P＜0.01),and both 207/206Pb and 208/206Pb were lower than those in urine(P＜0.01).There was a negative correlation between blood 207/206Pb,208/206Pb and blood lead levels(r=-0.562,-0.673,P＜0.01)and between blood 208/206Pb and urine 8-ALA levels(r=-0.416,P＜0.01).Urine 207/206Pb and 208/206Pb also showed a negative correlation with urine lead levels(r=-0.613,P＜0.01;r=-0.331,P＜0.05),and urine 206/206Pb had a negative correlation with blood ZPP levels(r=-0.636,P＜0.01).Conclusions Blood lead levels correlated well with blood ZPP and urine 8-ALA and were consistent with LIR in the environment.The difference in LIR in blood and urine indicated that lead may have"fractionation"after entering the human body.

Objective To optimize the method for determining lead isotope ratios(LIR)using a high-precision inductively coupled plasma mass spectrometer(ICP-MS),aimed at tracing the source of lead exposure in children with lead poisoning.Methods By optimizing data acquisition parameters and selecting relevant modes,an ICP-MS method for LIR determination was established.Four hospitalized children with lead poisoning were studied,and their blood samples,urine samples,and related environmental samples were collected.The established LIR method was applied to analyze the blood samples,urine samples,and environmental samples,and a two-dimensional source tracing model was used to trace the source of lead exposure.Results Under the optimized conditions of the instrument,the actual measured values of 204/206Pb,207/206Pb,and 208/206Pb were close to the certified values,at(0.058 88±0.000 22),(0.915 31±0.000 97),and(2.167 02±0.001 73),respectively;the precision of the measured values for 204/206Pb,207/206Pb,and 208/206Pb were 0.37％,0.11％,and 0.08％,respectively.In the lead source tracing of the poisoned children,the LIR in two children was similar to that of red lead powder used by themselves,and two children were related to environmental lead.Conclusions A more sensitive analytical method using an inductively coupled plasma mass spectrometer was established for the determination of LIR in blood,urine,and environmental samples and for analyzing the source of lead.

Objective To compare the measured results of arsenic in urine by atomic fluorescence spectrometry（AFS） and inductively coupled plasma-mass spectroscopy（ICP-MS）, and analyze the reasons of the difference. Methods The samples were pretreated according to WS/T 474-2015 Determination of Arsenic in Urine by Hydride Generation Atomic Fluorescence Spectrometry, and digested with mixed acid（nitric acid∶sulfuric acid∶ perchloric acid=3∶1∶1,V/V/V） and then determined by AFS and ICP-MS. The samples were diluted with 0.50% nitric acid and determined by ICP-MS. The samples included urine arsenic quality control samples, inorganic arsenic supplemented samples, and organic arsenic（arsenic choline and arsenic betaine） supplemented samples. Standard curve method was used to compare the results of AFS method and ICP-MS method.Results The results of quality control samples by AFS method（digestion） and ICP-MS method（without digestion） were within the range of reference values, but the values obtained by AFS method were lower than those obtained by ICP-MS method.The recovery of AFS and ICP-MS was 97.79%-100.82% and 99.55%-99.98%, respectively. In the middle and high concentration groups, the measured values of inorganic arsenic by AFS were lower than that by ICP-MS（all P＜0.01）. The recovery of arsenic betaine and arsenic choline by AFS method（digestion） was only 2.17%-2.63%. The values of arsenic betaine and arsenic choline measured by AFS method（digestion） were lower than those measured by ICP-MS method（without digestion） and ICP-MS method（digestion）（all P＜0.01）. Conclusion The result of urine arsenic measured by AFS method was lower than that measured by ICP-MS method, which may be related to the mixed acid digestion of AFS method.

backgroundThe lead isotope ratios (LIR) differ among different sourced samples. Previous domestic and oversea studies on source tracing by LIR in human blood or urine mainly focused on the comparison of blood or urine samples from the same or different individuals, while few comparisons between biological and environmental samples, and the reported relative standard deviations (RSDs) of the main LIR (207/206Pb and 208/206Pb) fluctuate widely from 0.3% to 1%. ObjectiveTo optimize inductively coupled plasma mass spectrometry (ICP-MS), obtain a better RSD, and determine LIRs of human blood, urine, and related environmental samples. MethodsThe ICP-MS was optimized for operating conditions and parameters according to the sensitivity and RSD of LIR. The study subjects were 40 lead-exposed workers in a lead-acid battery factory and 2 lead poisoned children in a hospital. The samples included 40 blood and 40 urine samples from the workers before shift, 4 dust samples and 2 water samples in the workplace on the same day before shift, 2 blood and 3 urine samples from the children before hospital admission due to lead-poisoning, and 4 urine samples after medical treatment. After heating and acid digestion, the LIR (207/206Pb and 208/206Pb) of biological and environmental samples were determined by the optimized ICP-MS method. t-test and two-dimensional traceability graphics were adopted to analyze the detection results. ResultsThe calibrated RSDs of the LIR (207/206Pb and 208/206Pb) of lead isotope standard solution were 0.11% and 0.08% respectively, and the NIST-SRM-981 actual values were 0.91531±0.00097 and 2.1670±0.0017, respectively. When the total concentration of lead was greater than 5 μg·L−1, the RSD of each isotope ratio was stable gradually; when the total concentration of lead was between 10-80 μg·L−1, the RSD was below 0.20%. There were statistically significant differences in the blood and urine LIR (207/206Pb and 208/206Pb) of the lead-exposed workers (t=5.831, P<0.001; t=21.021, P<0.001), the LIR (207/206Pb and 208/206Pb) between workplace dust samples and workers’ urine samples (t=−6.879, P=0.038; t=12.521, P<0.001), and the 208/206Pb between workplace dust samples and workers’ blood samples (t=−10.46, P<0.001), except the 207/206Pb between workplace dust samples and workers’ blood samples (t=−0.12, P=0.912). In the patients afflicted with lead poisoning, the projection points of LIR of blood and urine samples from the same individual were not at the same level in the two-dimensional model, nor was the LIR of urine samples before and after medical treatment of the same individual. ConclusionThe optimized ICP-MS can control the RSD of main LIR (207/206Pb and 208/206Pb) below 0.20%. There are differences in the LIR distributions of different samples.

目的 通过比对和评估不同模式和内标条件下的尿砷测定结果,建立和优化电感耦合等离子体质谱法(ICP-MS)测定尿中砷含量的分析方法.方法 在标准模式、碰撞反应池模式和动态反应池模式条件下,应用6Li、45Sc、74Ge、89Y、103Rh、115In、159Tb和209Bi等8种内标元素建立标准曲线并测定加标样品和质控样品,比对其相关系数、检出限、准确性和精密度.结果 不同模式和内标条件下相关系数基本一致(0.998 5～0.999 9),应用45Sc、74Ge、89Y、115In等4种内标的尿砷检出限优于6Li、10eRh、159Tb、209Bi,与此同时45Sc、74Ge、89Y、115In等4种内标碰撞模式和反应模式的检出限(分别为 0.003 9、0.003 3、0.004 8、0.003 3 μg/L 和 0.003 1、0.002 7、0.003 8、0.002 7 μg/L)低于标准模式(0.044 4、0.040 4、0.046 9、0.038 6 μg/L).在3种模式下,使用74Ge和89Y作为内标,尿砷测定结果均符合《化学试剂电感耦合等离子体质谱分析方法通则》的推荐要求.结论 在碰撞或反应模式下,使用74Ge和89Y作为内标,可有效消除尿的基体效应,该方法的曲线相关系数、检出限、精密度和准确性均符合要求,可应用于ICP-MS法测定尿中砷.

目的 建立适合于基础实验室应用的原子荧光法测定血中锡时的湿式消解方法.方法 取人体1mL全血,分别使用硝酸、盐酸、硫酸、过氧化氢以不同比例混合,置于石墨消解仪于90℃对血样进行消解,消解完成后加入200 g/L硫脲-抗坏血酸1 mL来掩蔽镍、铁、砷、硒等干扰离子,使用体积分数4％的盐酸溶液定容至10mL,采用氢化物发生-原子荧光法测定锡浓度.结果 依据不同消解组合的结果,提出优化的湿式消解方法为硝酸2 mL加过氧化氢2 mL于90℃消解样品1 h.在此条件下,质量浓度在4.00～200.00 μg/L范围内,原子荧光法测定锡的标准曲线线性关系良好,相关系数为0.999 5;方法 检出限为0.20 μg/L,加标回收率为99.76％～105.72％,批内精密度为0.21％～2.59％.结论 该湿式消解方法可使样品消解完全,待测元素损失少,基体干扰少,准确度和精密度较好,所用消解仪器便宜且在基层容易普及,适用于基层实验室对人血中锡浓度的测定.

[背景]我国尿砷检测的卫生行业标准未明确消化温度和电热板性能,导致不同实验室尿砷前处理方式存在较大差异.[目的]分析湿式消解-原子荧光法测定尿中砷结果偏低的原因,并对标准方法进行优化?[方法]以WS/T 474—2015《尿中砷的测定氢化物发生原子荧光法》推荐的步骤为基础,使用标准方法(150℃消解、220℃消解)和梯度升温方法(150℃消解1 h,220℃消解1 h,320℃消解30 min,消解赶酸至白烟散尽)对样品进行前处理,比对原子荧光法和ICP-MS法对尿液(高砷暴露的正常人群、服用砷剂病人和砒霜中毒病人)总砷和无机砷(亚砷酸根和砷酸根)、有机砷(砷甜菜碱和砷胆碱)标准品的测定结果.优化尿中砷测定的湿式消解-原子荧光法,并对其线性、检出限、定量下限、精密度、准确度和抗干扰能力等性能指标进行验证?[结果]150℃和220℃湿式消解原子荧光光谱法测定的结果回收率均低于90％,而梯度升温到320℃的湿式消解荧光光谱法测定结果与ICP-MS法接近,回收率为97.92％～101.16％.经过150℃和220℃的湿式消解,砷甜菜碱和砷胆碱几乎无法测出,回收率极低;梯度升温到320℃的湿式消解荧光光谱法测定砷甜菜碱和砷胆碱的回收率分别为97.59％和99.96％.该方法在尿砷含量为5.0～40.0μg·L-1时,线性关系良好,相关系数为0.9997,最低检出限为0.06μg·L-1,定量下限为0.18μg·L-1,相对标准偏差为0.95％～3.24％,加标回收率为95.95％～103.10％.200倍于砷水平的铅、锌、镉、铜、硒、汞、锑、铁、铝和锰等金属离子干扰物对测定结果所造成的偏差

We analyzed the lead levels in blood and urine from lead-exposed workers in Guangzhou and assessed the influencing factors. The data were analyzed by descriptive statistics, and the time-dependent changes were mapped via analytical statistics. Although the lead burden showed a clear downward trend over time, it remained high among the exposed workers. The highest lead burden was detected in workers of the electrical equipment manufacturing industry, especially among those in lead-acid battery factories where we did field studies. Hazardous as the working conditions of the original lead-acid battery factories were, there were improvements in the applications of occupational disease prevention measures after the relocation of factories, but the lead burdens were still above the average levels of lead-related industries. Improvements are needed in the management and regulations on occupational safety and health to further decrease the lead burden to acceptable levels.

对110例在我院同时进行血铅、尿铅、诊断性驱铅试验、尿δ-氨基-γ-酮戊酸和锌原卟啉等检查的病例检查结果进行比较和分析.结果 显示,观察对象筛查中血铅的灵敏度为73.77％,尿铅为37.70％,诊断性驱铅试验80.33％;轻度铅中毒病人筛查中ZPP灵敏度最高(81.82％),诊断性驱铅试验特异度、准确度和阳性预测值均最高(分别为100％、88.18％和100％).提示只采用单项检测指标筛查观察对象或诊断铅中毒,容易出现漏诊或误诊,应将几项指标联合应用.

根据尿中硫氰酸盐的吡啶-巴比妥酸分光光度法结合工作场所中氰化氢和氰化物测定方法,建立了异烟酸-巴比妥酸法测定尿中的硫氰酸盐.该方法检出限为0.17μg,方法的最低检出浓度为1.7 mg/L(按取0.1 mL尿样计);相对标准偏差范围:1.25％ ～1.99％,样品加标回收率为98.5％ ～103％.该方法安全度高、 重现性好、 准确度高,且符合尿液中的硫氰酸盐的测定要求,值得推广.

[目的]通过定期检测砷标准工作液的稳定性和准确性,研究其有效使用期限.[方法]依据《实验室标准物质管理指南》,参考相关文献,使用有证的标准物质对砷标准工作液的稳定性和准确性进行核查,评价结果是否在证书不确定度范围内,其定值是否依然可信.[结果]用于原子荧光光谱检测的砷及其无机化合物低浓度标准工作液,其质量浓度为20 μg/L的标准应用液在4℃冰箱中可保存超过63d;1.0 μg/mL的标准储备液,于4℃冰箱中可保存超过215 d,在此期限后,两者核查的结果准确度分别为8.92 μg/L、9.02 μg/L,超出不确定度下限9.22 μg/L,相对应的|En|值＞1,提示标准物质变化,应停止使用.[结论]实验室必须对低浓度标准储备液和标准应用液进行有效期验证,以确保使用时的结果准确.

Objective To establish a detection method for 1-bromopropane in human urine by headspace gas chromatography-mass spectrometry ( GC-MS) .Methods A 4.00 mL portion of the urine sample was placed in a 15.00 mL headspace vial and 20.00μL of 1-bromobutane internal standard solution (204.200 mg/L mass concentration) was added. The bottle cap was immediately sealed .The sample was heated to 80 ℃ with an equilibrium time of 20 minutes in the headspace device .The vapor in the headspace vial was separated by GSBP-FFAP ( 30.00 m ×0.25 mm ×0.25 μm ) capillary chromatography column and the ion was used to carry out quantitative determination of 1-bromopropane in human urine.Results The good linearity range of 1-bromopropan mass concentration was 0.025-1.012 mg/L, and the correlation coefficient was 0.999 8.The detection limit was 7.5 μg/L (urine sample volume, 4.00 mL) and the limit of quantitation was 25.0 μg/L (urine sample volume, 4.00 mL).The relative standard deviation (RSD) of within-run precision was 2.61%-4.08%, and the RSD of between-run precision was 2.79%-6.25%.The average recovery rate was 99.34%-105.94%.Conclusion The method of determining 1-bromopropane in human urine by headspace GC-MS has the features of high sensitivity , good linear relationship , low interference , good precision and easy operation , which is suitable for detecting 1-bromopropane mass concentration in human urine .

OBJECTIVE To investigate the forms of carbamazepine and its metabolites in the gastric juice,blood and urine samples from a poisoned patient and its metabolic pathways. METHODS The gastric juice,blood and urine samples were obtained from a patient who was rushed to the Hospital of Prevention and Treatment for Occupational Diseases to be treated for an overdose of carbamazepine for about six hours. The samples were analyzed by gas chromatography-mass spectrometry. The metabolites were identified from their mass spectra by comparison with spectra in NIST 98 libraries. The metabolic pathways were inferred by fragmentation regularities of mass spectra and the published data. RESULTS The results showed that only M1 was found in the gastric juice sample. Four metabo?lites,such as iminostilbene(M1),9-methyl-acridine(M2),9-propyl-acridan(M4)and M3,were found in the blood sample and thirteen metabolites,including M1,M2,M4,acridine(M5),acridone(M6), 9,10-dihydro Acridine (M7), 1a,10b-dihydro-6H-dibenz[b,f]oxireno[d]azepine-6-carboxamide (M8),9-acridinemethanol (M9),10,11-dihydrodiol-carbamazepine (M10),2-methyl-acridone (M12),4-methyl-acridone(M13),undetermined M3 and M11,were found in the urine from the poi?soned patient. The forms of carbamazepine metabolites in the gastric juice ,blood and urine were different. Little carbamazepine was found in the urine after metabolism. CONCLUSION Based on the analysis by gas chromatography-mass spectrometry and identification of NIST 98 libraries,the metabolites could be identified accurately,which can help analyze the metabolic mechanism and pathways of carbam?azepine.

Objective To establish a method for simultaneous detection of 5 anticoagulant rodenticides including brodifacoum, bromadiolone, flocoumafen, warfarin and difenacoum in whole blood by high-performance liquid chromatogarphy.Methods The 0.5 mL of blood sample was extracted by 2.0 mL ethyl acetate, then separated by Diamonsil C18 column (250.0 mm ×4.6 mm ×5.0 μm) using acid-ammonium acetate (20.0 mmol/L, pH=5.5)/methyl alcohol(2∶8, V/V) as a mobile phase and detected by diode-array detector under the ultraviolet spectrum of 310 nm through high-performance liquid chromatogarphy.Results The good linear range of the 5 anticoagulant rodenticides was 0.50-10.00 mg/L, and the correlation coefficients were >0.999 00.The detection limits of brodifacoum, bromadiolone, flocoumafen, warfarin and difenacoum were 0.08, 0.06, 0.09, 0.04 and 0.10 mg/L and the lower limits of quantitation were 0.79, 0.58, 0.92, 0.45 and 0.96 mg/L, respectively.The recovery rate was 98.40%-104.00%.The within-run relative standard deviation (RSD) was 0.61%-7.84%, and the between-run RSD was 1.10%-9.62%.The samples can be stored for 14 days in the refrigerator at 4 ℃.Conclusion The method has advantages of simple operation, good separating effect, high sensitivity, precision and accuracy, which is suitable for detection of whole blood samples in rodenticide poisoning patients.

Objective To establish a method for determination of urinary tin by atomic fluorescence spectrophotometry . Methods The graphite digestion instrument was used to digest 2.50 mL urinary sample with 1.50 mL concentrated nitric acid, hydrochloric acid (volume fraction 4.00%) was added to a total constant volume of 10.00 mL.After 2.50 mL of thiocarbamide-ascorbic acid (mass concentration 100 g/L) was added, hydrochloric acid (volume fraction 4.00%) was added to a total constant volume of 25.00 mL ( equivalent to urinary sample was diluted 10 times) , 1.00 mL of the sample was collected and detected by atomic fluorescence spectrophotometry .Results The good linear relationship was shown in the range of 4.00-200.00 μg/L with a correlation coefficient of 0.999 5.The limit of detection was 0.20 μg/L.The recovery rates ranged from 100.20%to 100.84%.The within-run relative standard deviation ( RSD) and between-run RSD were 0.11%-2.01%and 1.37%-5.58%, respectively .The samples can be stored for 7 days under the temperature of 4 ℃.Conclusion This method has the advantages of high sensitivity , precision and convenient operation , which is suitable for the daily determination of urinary tin in human .

目的 对《工作场所空气有毒物质测定锡及其化合物》(GBZ./T 160.22-2004)所使用的前处理方法进行调整改进,建立简便、准确的试验方法.方法 参照GBZ/T 160.22-2004方法,测定、计算滤膜中锡的质量;取1.0 mL浓盐酸(优级纯)和采样后的滤膜置于具塞比色管中,置50℃水浴中消解滤膜,测定、计算滤膜中锡的质量.对两种试验方法进行对比.结果 改进前,滤膜样品锡的回收率在50.0％以下,改进后回收率均在99.0％以上.结论 经调整改良后的前处理方法操作简便,回收率高,同时能减少对试验人员的伤害和酸污染的形成.

OBJECTIVE:To establish the method of high-performance liquid chromatography HPLC for the determination of N-acetyl-S-(2-carbamoylethyl)-cysteine (AAMA) in urine.METHODS:After acid hydrolysis, AAMA in urine was converted into S-2-carboxyethyl cysteine (CEC). CEC reacted with the derivative reagent ophthalaldehyde and formed the derivative with strong fluorescence absorption. The HPLC-fluorescence detector was applied, with an excitation wavelength of 340 nm and an emission wavelength of 450 nm.RESULTS:Urinary AAMA demonstrated an excellent linearity in the range of 5.3~123.5 μmol/L, with a correlation coefficient of 0.9994. The minimum detectable concentration was 0.1 μmol/L (the volume of urine sample was 1.0 ml), the recovery of standard addition was 97.4%~104.2%, and the between-run precision was 2.3%~4.3%. The sample could be stored in the refrigerator for at least 7 days at a temperature of 4℃.CONCLUSION:The method is simple, with a low cost, a high sensitivity, and good precision and accuracy, and the instrument and equipment commonly seen in laboratories are applied. Therefore, this method is worthy of wide application.