Detoxification of Mercury by Selenium by Binding of Equimolar

Determination of total mercury in bauxite and bauxite residue by flow injection cold vapour atomic absorption spectrometryNeetu Bansal a ,⁎,James Vaughan a ,Amiel Boullemant b ,Tony Leong ca School of Chemical Engineering,The University of Queensland,Australiab Rio Tinto Alcan Technology QRDC,Australia cQueensland Alumina Limited,Australiaa b s t r a c ta r t i c l e i n f o Article history:Received 9October 2013Received in revised form 4November 2013Accepted 4November 2013Available online 13November 2013Keywords:Mercury determination FI-CV-AAS BauxiteBauxite residueMicrowave digestionA simple method for precise and accurate determination of total mercury in bauxite and bauxite residue was de-veloped by using the flow injection mercury system.Samples of the solid materials were first microwave digested in acidic and oxidising conditions to convert all mercury to an aqueous ionic form.Following filtration and dilution,ionic mercury was reduced to elemental mercury with acidic SnCl 2to produce a cold mercury vapour.The mercury absorbance calibration graph was linear up to 20μg·kg −1with R 2N 0.999.The detection limits were determined to be 23ng·kg −1and 17ng·kg −1for bauxite and bauxite residue respectively.The relative standard deviation for 1μg·L −1mercury standard solution (n =27)was 1.5%.In the absence of a certi fied baux-ite reference material,accuracy of the method was tested with the closest available zinc concentrate reference material.Spiking known amounts of mercury in bauxite and bauxite residue samples was also tested;95–111%recovery was obtained for both samples.The method developed in this paper is recommended for measuring total mercury in bauxite and bauxite residue.©2013Elsevier B.V.All rights reserved.1.IntroductionMercury has long been recognised as a neurotoxic element [1].It is ranked third in the “priority list of hazardous substances ”by the United States Comprehensive Environmental Response,Compensation,and Liability Act [2].The United Nations also finalised the legal document “Minamata Convention of Mercury ”with the aim to reduce mercury emission;140countries are signatories to this convention [3].Recognising the growing international concern over mercury emissions,the International Council on Metals and Mining (ICMM)adopted a Mercury Risk Management Position Statement to position its members in a leadership role on the issue [4].Rio Tinto Alcan and Queensland Alumina Limited began collaboration with the University of Queensland in 2011to develop an improved understanding of mercury in their operations.Mercury can be found both naturally as well as introduced into the environment by anthropogenic activities [5].Reliable monitoring of mercury release and distribution is challenging due to issues with both sampling and measurement.Many instrumental analytical methods can be employed to determine the trace level of mercury in various samples.The most commonly cited techniques are:atomicabsorption spectrometry [6–11],atomic florescence spectrometry [12–15],inductively coupled plasma mass spectrometry (ICP-MS)[16–19],inductively coupled plasma atomic emission spectrometry (ICP-AES)[20],electroanalysis [21,22],and neutron activation analysis [23,24].Cold vapour atomic absorption spectrometry (CV-AAS)is a widely used method because of its high sensitivity and selectivity for mercury.This method involves generation of elemental mercury from an acidi-fied solution with a reducing agent (e.g.SnCl 2,NaBH 4)or by other means such as photoreduction,electrochemical (EC)vapour generation,and ultrasound promoted cold vapour generation [25].The CV-AAS technique requires that the elemental and organic forms of mercury be oxidised into ionic mercury in the feed solution [8].The conversion of complex solids into an aqueous form is accom-plished by heating the samples with concentrated acids.Wet digestion is used most commonly as mercury is lost to the vapour phase during dry ashing.Oxidants are also employed during wet digestion with the most common acids and oxidising agents being HCl,HNO 3,H 2SO 4,HClO 4,KMnO 4,K 2Cr 2O 7and H 2O 2.Elemental mercury,methyl mercury,dimethyl mercury are potential volatile components of the mercury species in a sample.Due to these volatile components,along with the tendency of mercury to adsorb on vessel walls and the requirement for complete digestion of the mercury,care must be taken in the selection of respective digesting agents and overall procedure.The choice of digestion acid depends upon the type of sample and the form of mercury present in the sample.For example,samplesMicrochemical Journal 113(2014)36–41⁎Corresponding author.E-mail address:neetu.bansal@.au (N.Bansal).0026-265X/$–see front matter ©2013Elsevier B.V.All rights reserved./10.1016/j.microc.2013.11.002Contents lists available at ScienceDirectMicrochemical Journalj o u r na l ho m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /m i c r o ccontaining organic mercury need strong oxidising agents such as aqua regia and bromine monochloride solution.Samples high in silica may require hydrofluoric acid for complete solid dissolution.Perchloric acid also has strong oxidising power but can be dangerous for the sam-ple high in organic content and it requires heating N200°C to achieve its maximum oxidising power[26].The sample preparation step in mercury determination is a challeng-ing part of the process,as it consumes time and can result in loss of analyte due to its volatile nature.Pressure microwave digestion is a good alternative to ambient pressure digestion[27].The advantages of pressure digestion are a fast digestion time,greater accuracy,less consumption of reagents,reduced sample size and less contamination [28–31].Bauxite ore is a sedimentary rock that arises due to weathering of volcanic rocks[32].The minerals are generally well oxidised with alu-minium,iron and silicon being the major components.Metallurgical grade alumina is produced from bauxite ore using the Bayer process which involves digestion of bauxite with hot sodium hydroxide under high pressure at temperatures in the range of130°C to280°C depending on the feed material.Bayer process residue(bauxite residue) is the fraction of the bauxite ore that remains undigested.The mercury content of bauxite ore can vary significantly with values of20–100, 500–700and1200–2000μg·kg−1being reported[33].The mercury varies with the geographical origin of bauxite ore[34]and,within a single deposit,mercury content can also vary significantly.To reliably ascertain the total mercury content bauxite ore and bauxite residue,a robust method was developed using microwave digestion andflow injection mercury system(FIMS)on the resulting solution.The main challenges in the development of the procedure are the presence of trace and variable amounts of mercury and complex matrix of bauxite and bauxite residue.2.Experimental2.1.ReagentsDeionised water(greater than1.0MΩcm resistivity)was used to prepare the solutions.All reagents were of analytical grade and checked for trace mercury contamination.A1.2%(w/v)SnCl2reagent was freshly prepared by dissolving12.0g SnCl2.2H2O in30mL HCl and diluted up to1L with deionised water.Mercury stock solution1000mg·L−1in 10%(v/v)HNO3was supplied by Perkin Elmer Australia.Other stock solution was prepared by diluting this mother stock solution with deionised water and1mL BrCl as a preservative for50mL solution. Mercury calibration solutions(0.5to20μg L−1)were prepared from di-lution of the mother stock solution prior to each experiment.Hydrogen peroxide(30%w/w)was supplied by Fluka Analytical,and used as such without further dilution.Bromine monochloride solution was prepared byfirst mixing5.4g of KBr(Sigma Aldrich)in50mL HCl for1h,7.6g KBrO3(Sigma Aldrich)was then added slowly over a period of approx-imately5min to produce the BrCl solution.Hydroxylamine hydrochlo-ride was prepared by dissolving15g NH2OH.HCl in deionised water to a final volume of50mL.Aqua regia(3HCl+1HNO3by volume)was prepared immediately prior to digestion.Argon gas with N99.95%purity (Core gas)was used in all experiments.The concentrated acids(HCl-37%,H2SO4-95%,HNO3-70(w acid/ w solution)%)were supplied by Sigma Aldrich.They are used with-out dilution unless specified.When diluted,the percentage speci-fied throughout the paper refers to volume percentage:100%∗(V concentrated solution/V diluted solution).2.1.1.Reference materialValidation of the method described in the present work was performed using zinc concentrate reference material BCR®-109 (Institute for Reference Material and Measurements).2.2.Instrumental2.2.1.Microwave digesterFor the digestion process a speed wave®4(Berghof products)+ instruments GmbH Germany,digester with DAK-100pressure vessels was used.The pressure vessels are made of TFM-PTFE which has a high chemical resistance and hydrophobicity.The vessels are rated up to100bars with a maximum temperature of300°C.To provide a com-fortable safety margin,the maximum temperature applied in this pro-cedure was230°C.The pressure is monitored continuously by a contact free,optical system along with temperature by an external in-frared based estimate.The microwave digestion of bauxite and bauxite residue was carried out in stages,in thefirst stage,the reactor contents were heated to120°C(maximum pressure60bars)for6min with a ramp up time3min followed by heating at200°C for5min with ramp up time of3min.In the third stage,the solutions were heated at230°C for16min with a ramp up time of5min.The total time required for digestion is about45min(including cooling time in the microwave digester).2.2.2.Flow injection mercury system(FIMS)A Perkin Elmer FIMS400flow injection mercury system is employed for the determination of mercury content of the diluted digestion liquor. This instrument uses a high performance single beam optical system, solar blind detector and low pressure mercury lamp.Thisflow injection system consists of two peristaltic pumps(P1,P2),a24cm long absorp-tion cell with removable quartz window,electrically heated mantle to maintain the cell temperature at approximately50°C.Theflow injec-tion switching valve hasfive ports with variable length sample loops. The tubing is made of PTFE and the gas liquid separator is a membrane also made of PTFE.FIMS is a combination of theflow injection technique with atomic absorption detection.The hardware was controlled using the Perkin Elmer Win Lab32for AA system software.The instrumental operating conditions are given in Table1.SnCl2/HCl was used as reductant and argon gas was used as a carrier of mercury vapour to the absorption cell.2.3.Sample collection and nature of samplesThree different bauxite and two different bauxite residue samples were collected from various alumina refineries and mining sites. Samples were collected and placed in plastic containers and transported to the lab.2.4.Characterization of bauxite residue and bauxiteThe main components of bauxite and bauxite residue samples were quantified by XRF(X-rayfluorescence),the bauxite content was 44–53%Al2O3,14–27%Fe2O3,3.8–7%SiO2,2–2.5%TiO2as wt.%andTable1Characteristic parameters of FIMS.FIMSWave length253.7nmLamp Electrodeless discharge mercury lamp(EDL) Measurement Peak heightFIAS prefill time15sFIASfill time10sFIAS inject time15sRead delay0sRead time15sReductant 1.2%(w/v)SnCl2in3%(v/v)HClCarrier3%(v/v)HClCarrier gas stream ArgonCarrier gasflow rate50mL·min−1Cell temperature50°CSample loop500μL(can be variable)37N.Bansal et al./Microchemical Journal113(2014)36–41bauxite residue content was15–23%Al2O3,27–30%Fe2O3,10–19%SiO2, 4.7–6.5%TiO2as wt.%.The major mineral phases present in the samples were identified by XRD(X-ray diffraction)using the PDF-22012data-base.The results indicate the major components of bauxite-1,bauxite-2and bauxite-3are gibbsite(Al(OH)3),boehmite(γ-AlOOH),hematite (Fe2O3),and kaolinite(Al2Si2O5(OH)4).XRD patterns for the bauxite samples are similar despite coming from various deposits.The baux-ite residue samples showed the presence of mostly hematite and some boehmite.Certain peaks for the bauxite residue XRD patterns remain unidentified.Of the unidentified peaks,some were matching with sodium aluminium silicate compounds but there was no com-plete match with the compounds in the database.The sodium aluminium silicate is the result of a desilication process which ex-plains the elevated sodium content in the residue[35].Calcium and magnesium contents are also elevated in the residue due to addition of lime during the process and a seawater neutralisation process.The literature shows the presence of aluminium hydroxide as major component and iron oxide,clay,titanium oxide,quartz,water and some other minerals as minor components in bauxite samples[36]. On the other hand the bauxite residue samples contain iron oxide and silica as major component and alumina and some other metal oxides as observed here[37].2.5.Sample preparationSample preparation is a critical step in accurate mercury content determination.As bauxite ore has a non-uniform distribution of mineral phases,the sample preparation step becomes important to obtain a representative sample and measure a sufficient quantity of sample to assess the natural variability.2.5.1.Mineral processing20kg bauxite samples were rotary split to about2.5kg fractions and one of the2.5kg fraction was then riffle split to about300g.Before splitting,the coarse fraction of the bauxite was crushed with a mortar and pestle.Finally,bauxite samples were staged pulverised for two cy-cles of5s to minimise mercury loss due to heat produced.The material was then sieved through a300μm mesh screen.The oversized material was re-pulverised for5s until all the material passed through the 300μm mesh.2.5.2.Digestion of samplesTo dissolve the sample matrix,wet digestion was carried out using a combination of acids at high temperature in the microwave digester. The hot,wet digestion can solubilise both inorganic and organic matter. Microwave digestion may enhance contact between acid and particle by fracturing particle that results in providing a new surface for acid attack [38].Careful selection of acid is required for optimal digestion.A combi-nation of aqua regia and hydrogen peroxide worked well for digesting bauxite and bauxite residue samples leaving behind a silica rich residue. Addition of H2O2in the digestion mixture facilitates the complete oxida-tion of organic matter.For the digestion of bauxite and bauxite residue, closed vessel microwave digestion with varying combinations of acid was systematically evaluated.From an analytical point of view;it is dif-ficult to solubilise bauxite and bauxite residue due to the high silicates/ silica content without using hydrofluoric acid.Also,increasing the amount of acid used can compromise the measurement using FIMS. Some researchers have claimed that digestion with acid can leach all the mercury from the sample into the acid solution and remove silicates byfiltration[39–41].The use of hydrofluoric acid to solubilise silica was avoided,due to its hazardous nature and its adverse effect on the FIMS [42].As mercury has no tendency to form natural silicate material,it was not deemed necessary to dissolve silica in the digestion mixture [43].2.5.3.Bauxite digestionFor the digestion of bauxite,various combinations of acids were test-ed.In each method0.5g of bauxite was digested with single and/or combination of various acids in the microwave digester.2.5.4.Bauxite residue digestionBauxite residue samples were digested as slurry.Before weighing the sample,bauxite residue was stirred for at least1h to make sure it is homogenous.A3.5g of bauxite residue sample was digested with dif-ferent combinations of acids.Moisture content of the bauxite residue was approximately60%that was measured separately after drying a sample in oven at60°C to constant mass.2.6.Calibration matrixThe mercury standard solution was treated exactly as the sample solutions and underwent every step including microwave digestion with the same reagents.Calibration blanks were also prepared in reagent water containing the exact amount of digestion mixture and preservative with no mercury and treated like a sample.2.7.Analytical procedureA0.5g bauxite or3.5g bauxite residue was weighted directly in the TFM-PTFE in-liner vessel.The digestion procedure was carried out in two steps,predigestion and closed vessel microwave digestion.In the pre-digestion step,for bauxite samples,3mL HCl and1mL HNO3 were added followed by drop by drop addition of1mL H2O2over a time period of approximately1min.These samples were kept over-night to ensure the oxidation of all organic matter and total degassing in solution prior to microwave digestion to prevent the build-up of extra pressure due to generation of carbon dioxide gas.For the bauxite residue samples,the same procedure was adopted,except that the amount of acid was3.75mL HCl and1.25mL HNO3.During the pre-digestion step,the PTFE vessels were loosely capped.The following day water was added to the pre-digested sample to a total volume of 15mL.The in-liners were then placed in the pressure vessels and the digestion procedure was carried out.After digestion,the pressure vessels were cooled(to room temperature)for a minimum of2h.After cooling,750μL of BrCl was added as a mercury preservative and also to assist with the conversion of any remaining organically com-plexed mercury into ionic mercury.After3–4h,the digested samples were transferred to a50mL centrifuge tube along with the washings from the TFM-PTFE in-liner.All the samples were centrifuged for 15min at5000rpm.After centrifuging,the solution was carefully transferred to another centrifuge tube leaving behind a white silica rich residue.The bauxite sample typically had less residue compared to the bauxite residue sample,this was attributed to the relatively high silica content of the residue.The digested decanted sample solution was thenfiltered through0.2μm PTFE syringefilter,and diluted to50mL with deionised water for analysis by FIMS.15min prior to the analysis,hydroxylamine hydrochloride solution was added to neutralise remaining BrCl.3.Results and discussionFIMS sensitivity is highly dependent on cold vapour generation which in turn depends on the experimental conditions.To determine the optimum conditions for the given method from the FIMS,physical and chemical variables were studied at10μg·L−1mercury.3.1.Chemical parameters3.1.1.Effect of SnCl2The effect of SnCl2on recovery of10μg·L−1mercury was studied. The concentration of SnCl2was varied from0.01%(w/v)to7%(w/v).38N.Bansal et al./Microchemical Journal113(2014)36–41The best recovery(100%)was obtained between1.0and2.0%SnCl2.This is in close agreement with the recommended concentration given by the supplier of FIMS.Reductant concentrations below1.0%and above 2.0%result in decreased recovery of mercury.1.2%SnCl2was chosen as the optimum value.3.1.2.Effect of HCl concentration in SnCl2To obtain clear solutions for aqueous SnCl2required dissolution in dilute HCl.Hydrochloric acid concentrations were varied from0.1% (v/v)to7.0%(v/v).Results showed100%recovery when the HCl content of the SnCl2solution was in the range of3.0%to4.0%.3%HCl was selected for experiments.3.1.3.Effect of HCl as a carrierThe concentration was varied between0.01%(v/v)and10%(v/v). The optimal range was determined to be3–4%HCl for10μg·L−1 mercury and3%HCl was selected for study.3.2.Physical parameters3.2.1.Argonflow rateArgon was used as carrier gas,the effect of gasflow rate was de-termined over the range of30to130mL·min−1(Fig.1).Argon flow rate also plays an important role in the sensitivity of the instru-ment as this carrier gas is responsible for carrying mercury vapour from the gas liquid separator to the absorption cell.Absorbance of the mercury signal was increased with argonflow rate from30mL·min−1 to50mL·min−1and reaches a maximum value at50mL·min−1and again decreases with increasingflow rate.At high argonflow rates the sensitivity decreases considerably due to reduction in residence time and dilution of the mercury vapour by argon gas.50mL·min−1was se-lected as the optimum value.3.2.2.Reagentflow rateThe maximum absorbance was observed when acid and reducing agentflow rates were10and6mL·min−1respectively.3.2.3.Effect of sample volumeThe effect of the sample volume was studied from20μL to 1000μL for absorbance of10μg·L−1mercury.Absorbance increased with increasing volume size from20–500μL,but from500–1000μL the absorbance plateaued.Results are shown in Fig.1.500μL was se-lected for further parison of oxidising agentsTo determine the optimum digestion working conditions for bauxite and bauxite residue samples,different combinations and amounts of digestion mixture were tested for microwave digestion. Total solubilisation of bauxite and bauxite residue was not required as mercury has no tendency to form silicates due to its large ionic radii [44].Initially,different individual acids and combinations of oxidising agent and acid at various amounts were tested.A result showed be-tween4and5mL acid/acid combinations was sufficient and efficient to digest0.5g bauxite in the microwave digester.Next about5mL of acid or combinations of different oxidising agents were tested.This study has been performed on the bauxite-1samples.A single factor Anova test was carried out at95%confidence interval.For one type of study,samples from a specific refinery were selected and taken from one container only.3.3.1.Aqua regia digestionIn this series of digestions,0.5g of bauxite was mixed with increas-ing amounts of aqua regia.The same procedure was followed as given in Section2.7including addition of BrCl.It is desirable to minimise the aqua regia required for digestion,as large amounts of aqua regia in-creases the detection limit of the assay.The results show(not included) 4mL aqua regia is sufficient to digest0.5g bauxite ore.The optimal value of4mL aqua regia was also verified for a second bauxite sample (results not shown).The lower observed recovery of mercury for higher aqua regia concentration could be related to decreased absorbance in FIMS.3.3.2.Other digestionsOther methods tested for digestion of bauxite are,4mL aqua regia+1mL H2O2,5mL HNO3,4mL HNO3+1mL H2SO4, 4mL HNO3+1mL HCl, 2.5mL HNO3+2.5mL HCl, 2.5mL HNO3+2.5mL HCl+1mL H2O2.In all these digestion the same pro-cedure given in Section2.7was followed.After testing different diges-tion mixtures,results showed that to digest0.5g bauxite,4mL aqua regia and1mL H2O2gave the best recovery of total mercury.Likewise, for the digestion of bauxite residue samples,different combinations of aqua regia and H2O2were tested.The highest recovery of mercury from bauxite residue samples using3.5mL slurry needed5mL aqua regia and1mL H2O2.3.4.Effect of sample drying temperature on recovery of mercury in bauxite sampleThe effect of drying temperature on bauxite-3was studied for a temperature range of40–240°C.For each temperature,sampleswere0.12Sample volume (µL)AbsorbanceforHgArgon gas flow rate [ mL. min-1]samplevolumeFig.1.Effect of argonflow rate and sample volume on absorbance at10μg·L−1mercuryconcentration(error barsrepresents the standard deviation of triplicate data point).[Hg]µg.kg-1Temperature in ⁰CFig.2.Effect of drying temperature of bauxite-3on mercury recovery(duplicate samples).39N.Bansal et al./Microchemical Journal113(2014)36–41dried for48h in the oven.Fig.2shows that increasing the temperature results in a minor loss in mercury concentration from40to80°C. Further increasing the temperature from80to120°C,there is a sharp decrease in the recovery of mercury that shows a major loss of the volatile mercury that occurs in this region.3.5.Validation of the method and analytical results of samplesFive point calibration curves with R2N0.999were constructed with the microwave digested mercury standard solution using the same amount of digesting mixture.In the absence of an appropriate bauxite reference material,the method was tested using a zinc ore reference material(Certified reference material BCR109)and by using spike and recovery experiments.The certified value for mercury was 960±120μg·kg−1(mean±standard deviation).Measured value for reference material in this study was973±34(mean±standard deviation)for9replicates.Two statistical tests were conducted to com-pare our results of the certified reference material to the certified value provided by the supplier.A t-test[45]compares the sample mean valueto the standard value.In the t-test,t calc was1.14and t tab was1.83at95% confidence interval for9degrees of freedom.As t tab N t calc,there is not sufficient evidence to reject the null hypothesis,which proves that both of the values are statistically similar.In another test,the confidence interval calculated for the certified value was960±98μg·kg−1at95% confidence interval and the measured value(973μg·kg−1)is within range.Bauxite and bauxite residue samples analysed by FI-CV-AAS are given in Table2.Fig.3shows the variability of the mercury content. For quality control,a known concentration mercury solution was analysed after every four samples.Accuracy was determined by 80–120%mercury recovery.To evaluate the variability of mercury concentration within the samples a single factor Anova[45]test was performed on all samples. Results showed in all the samples that there was enough evidence to reject the null hypothesis at≈100%confidence interval as F N F critical, this proves that there is natural variability in the samples.In another attempt an Anova test with Tukey method[46]was performed to compare the mercury contents in all samples.Results showed that the mercury content of bauxite-1and bauxite-2are not statistically differ-ent and the same results were seen in bauxite residue-1with bauxite residue-2.On the other hand the mercury content of bauxite-3is statistically different from bauxite-1and bauxite-2.Mercury present in bauxite is also statistically different and considerably greater than in the bauxite residues.For validation of the method,spike and recovery experiments were done by adding increasing concentrations of mercury to bauxite-1samples and bauxite residue-1samples with digestion of the mixture in the microwave digester.The procedure was repeated for each addition as described in Section2.7.Results are given in Table3.The recoveries for spiked bauxite and bauxite residue samples were between95and111%.3.6.Analyticalfigure of meritThe analyticalfigure of merit of the proposed method was calculated under optimised condition.The calibration curve was linear up to 20μg·L−1with standard solutions of mercury.The precision was calcu-lated as repeatability of the signal.It was determined from the analysis of27replicate sample of microwave digested mercury standard solu-tion containing1μg·L−1mercury with a relative standard deviation of1.5%.The method detection limit(MDL)was calculated by a U.S. EPA method[47].MDL was calculated for the bauxite and bauxite resi-due matrix.Bauxite-1sample was heated to150°C for24h to produce low mercury bauxite.This bauxite sample was used to calculate detection limits as its mercury concentration was reduced between one tofive times the estimated detection limit[47].The detection limit calculated for12samples of the bauxite at95%confidence interval was23ng·kg−1.The detection limit for bauxite residue matrix was determined to be17ng·kg−1at95%confidence interval based on10 samples from the same batch of residue.4.ConclusionA simple and accurate method for the determination of total mercu-ry in bauxite and bauxite residue samples by FI-CV-AAS was developed. The method yields lower detection limits than those stated in the liter-ature for the CV-AAS method and is sufficiently low for measurement of mercury in both bauxite and bauxite residue.Satisfactory relative stan-dard deviation values were obtained for standard solution of mercury and the method was also validated using a zinc concentrate mercury reference material.Method performance and validation were checked by quantitative recovery of mercury from spiked bauxite and bauxite residue samples.This method was successfully applied to assess the natural variability of mercury in the samples.Based on the outcomesTable2Results of bauxite and bauxite residue by FI-CV-AAS.Sample Measured value(μg·kg−1)a No.of samples Tukey method groupinginformation at95%confidence intervalBauxite-144±1224A Bauxite-246±1216A Bauxite-3135±2118B Bauxite residue-110±326C Bauxite residue-27±18Ca Mean±standard deviation.b au xi t eb au xi t eb au xi t eb au xi t er es i du eb au xi t er es i du e[Hg](µg•kg-1)Fig.3.Variability of mercury in bauxite and bauxite residue samples.Table3Analytical results of mercury in spiked bauxite and bauxite residue sample.Samples Hg added(μg·kg−1)Hg found(μg·kg−1)aHg recovered(μg·kg−1)aRecovery(%)aBauxite-1042––150195152101±3275339297108±4650765723111±3 Bauxite residue-109––556859107±112512811995±1286306297104±1a n=3,mean±mean deviation.40N.Bansal et al./Microchemical Journal113(2014)36–41。

第49卷第1期 当 代 化 工 Vol.49，No.1 2020年1月 Contemporary Chemical Industry January，2020收稿日期：2019-03-20氢化物发生-原子荧光法测田螺中硒、汞余文丽1，王振生1，王小强2（1. 河南有色金属地质矿产局第七地质大队，河南 郑州 450018； 2. 河南省有色金属地质勘查总院 ，河南 郑州 450052）摘 要： 为了提高分析测试工作效率，探索了双道氢化物发生-原子荧光法同时测定田螺中硒、汞的分析方法，该实验采用硝酸-高氯酸消解样品，以盐酸为预还原剂，KBH 4为还原剂，确定了最佳反应条件和仪器工作条件，并对试剂进行了选择和优化，同时针对硒和汞之间的相互干扰进行了分析。

结果表明，荧光强度与硒、汞浓度在0~8 ng/mL 范围呈良好线性关系，硒和汞的检出限分别为0.043 9、0.004 2 ng/mL，回收率分别为92.5%~101%，78%~87%，并且硒和汞之间的干扰可忽略不计。

该方法操作简便，灵敏度高，结果稳定可靠，具有较好的精密度及准确度，并且实现了硒、汞同时测定，降低了分析成本，提高了工作效率。

关 键 词：氢化物发生-原子荧光法；田螺；硒；汞中图分类号：O655.1 文献标识码： A 文章编号： 1671-0460（2020）01-0204-04Determination of Selenium and Mercury in River Snail by Hydride Generation -Atomic Fluorescence SpectrometryYU Wen-li 1, WANG Zhen-sheng 1, WANG Xiao-qiang 2（1. Henan Provincial Nonferrous Metals Geological and Mineral Resources Bureau No. 7 Geological Team,Henan Zhengzhou 450018, China;2. General Institute for Nonferrous Metals and Geological Exploration of Henan Province, Henan Zhengzhou 450052, China ）Abstract : A method of simultaneously determining Hg and Se in river snail was developed for improving the analytic efficiency by hydride generation-double channel atomic fluorescence spectrometry,using nitric acid-perchloric acid to digest samples, using hydrochloric acid as pre-reducing agent, KBH4 as reducing agent. The best reaction conditions and the instrument working conditions were determined. The reagents were selected and optimized, and the interference between selenium and mercury was analyzed. The results showed that its linear range was 0~8 ng/mL for Se and Hg, the detection limit and recovery were 0.043 9 ng/mL and 92.5%~101% for Se, 0.004 2 ng/mL and 78%~87% for Hg, and the interference between selenium and mercury was negligible. The method is simple, stability and highly accurate, the simultaneous determination of selenium and mercury can be realized,which reduces the cost of analysis and improves the work efficiency.Key words : Hydride generation-atomic fluorescence spectrometry ；River snail ；Selenium ；Mercury硒是人体必需的微量元素之一，人体缺硒或摄入量过多均会导致相关疾病或不良反应[1]。

检测认证五氯苯酚检测标准技术分析与展望■ 宋玉峰（山东省产品质量检验研究院）摘 要：五氯苯酚因其防霉杀菌作用广泛应用于多个领域，在保护消费品品质的同时存在潜在健康风险。

科学有效地检测识别这类物质是了解与防范其安全风险的基础。

本文梳理了国内外五氯苯酚痕量迁移物现行检测标准，概述并比较其迁移物提取的前处理实验流程和检测技术方法，通过前处理流程及检测技术的梳理解析，分析比较过程的复杂性和操控性、试剂的环保性，探讨实验技术的优化及改进。

本文以期为五氯苯酚检测过程中绿色环保的改进、提高检测过程的可操控性等提供参考。

关键词：五氯苯酚，有害物质迁移，前处理技术，健康风险DOI编码：10.3969/j.issn.1002-5944.2023.15.036Prospect and Technological Analysis of DetectionStandard for trace pentachlorophenol MigrationSONG Yu-feng（Shandong Institute for Product Quality Inspection）Abstract:Pentachlorophenol is extensively applied in many fields due to its anti-bacterial and anti-fungal effects, which facilitates the quality of products and has health risks. Effective identification of these substances is the basis of understanding and preventing safety risks. The paper sorts out current detection standards to trace phentachlorophenol migration at home and abroad. The paper presents and compares the pretreatment experimental processes and technological testing methods, analyzes the complexity, controllability, and environmental effects of reagents by sorting out pretreatment processes and testing methods, and discusses the improvement of experimental technologies. The paper provides reference for improving the greenness and controllability of pentachlorophenol detection process.Keywords: pentachlorophenol, migration of harmful substances, pretreatment technology, health risk0 引 言五氯苯酚及其盐和酯类物质防霉杀菌效果好，价格优势明显，使用方便，作除草剂、防腐剂和防霉剂广泛用于多个领域。

1适用范围及应用1.1该方法是通过测浓度、immunomagnetic分离(IMS)和免疫荧光分析(FA)显微镜来检测水中的隐孢子虫(CAS登记号137259-50-8)和贾第虫属(CAS登记号码137259-49-5)。

隐孢子虫和贾第虫属可以使用DAPI染色法和微分干涉差显微镜(DIC)法来证实。

在地表水的方法进行验证,但可以使用其他水域,提供实验室演示了。

1.2这种方法的目的是满足的调查和监测要求美国环境保护署(EPA)。

它是基于实验室的测试EPA召集的由一个专家小组的建议。

面板被指控推荐一种改进协议复苏和原生动物的检测,可以检测并实现以最小的额外的研究。

1,3该方法识别属、隐孢子虫和贾第虫属,但不是物种。

该方法不能确定主机物种起源,也不能确定检测的可行性或传染性卵囊和囊肿。

1.4此方法仅供有经验的人使用通过过滤、IMS和FA决定隐孢子虫和贾第虫属。

有经验的人在22.2节中定义为分析师或首席分析师。

熟悉实验室环境样品的分析技术在这个方法应该使用水过滤技术获得经验,IMS,与单克隆抗体荧光抗体染色,显微镜检查使用亮场和DIC显微镜生物微粒。

1.5任何修改方法的超越明确允许的应用程序和批准的替代测试程序在40 CFR 141.27部分。

2方法概要2.1水样过滤，并且卵囊囊肿和附加材料留存在过滤器上。

虽然EPA只验证了使用实验室的批量水样过滤的字段的方法，field-filtration也可能被使用。

2.2洗脱和分离2.2.1材料在过滤洗提，洗出液离心成颗粒卵囊和囊肿，且上清液吸气。

2.2.2卵囊和附件囊肿是磁化的磁珠共轭anti-Cryptosporidium和anti-Giardia抗体。

磁化卵囊和囊肿使用磁铁分开从无关的材料，无关的材料被丢弃。

磁珠复杂的是脱离卵囊和囊肿。

2.3枚举2.3.1卵囊和囊肿是彩色幻灯片和荧光标记的单克隆抗体4’,6-diamidino-2-phenylindole(DAPI)。

Vol. 13 ,No.2March 2021第13卷第2期2021年3月环境监控与预警Environmental Monitoring and Forewarning !监测技术！DOI : 10. 3969/j. issn. 167^6732. 2021.02. 005超高效液相色谱-串联质谱法测定水中拟除虫菊酯 和有机磷农药残留杨敏娜，秦兴秀，王来梁（江苏省地质调查研究院自然资源部国土（耕地）生态监测与修复工程技术创新中心，江苏 南京210018 %摘 要：采用直接进样法和萃取浓缩法2种前处理方式，通过超高效液相色谱-串联质谱法对水中20种拟除虫菊酯类和 有机磷类农药进行了测定，并对仪器条件的选择和前处理条件的优化进行了探讨$结果表明,20种农药的线性关系良好,相关系数均〉0.999，直接进样法检出限为0.21 -2.47 'g/L ,回收率为81.0% -119%，相对标准偏差＜10% $萃取浓缩法检出限为0.002 2 -0.004 3 'g/L ,回收率为71.5% -115%，相对标准偏差＜15% $该方法简便、快捷，精密度和准确度较高，可满足水中拟除虫菊酯类和有机磷类农药的检测要求$关键词：超高效液相色谱-串联质谱法；拟除虫菊酯类农药；有机磷类农药中图分类号：X832 ；O657.63文献标志码:B文章编号：1674 -6732 （2021） 02 -0024 -05Determination of Pyrethriod Pesticide and Organic Phosphorus Pesticide Residues in Water by Ultra Performance Liquid Chromatography 一 Tandem Mass SpectrometryYANG Min-na , QIN Xing-xiu , WANG Lai-liang% Cultivated Land Ecological Monitoring and Restoration Engineering Technology Innovation Center of Ministry ofNatural Resourcet , Geological Survey of Jiangsu Provinco , Nanjing , Jiangsu 210018 , China )Abstract : A method for determination of 20 organic phosphorus and pyrethriod pesticides in wateo was established by using ultroperformance liquid chromatography - tandem mass spectrometiy after direci injection or after extraction and concentrated. Theinstrumeni ccnditions and pretreetment ccnditions were optimized. The regression equation of 20 kinds of pesticides showed goodlinear relationship , the ccrrelation coefficients were all greater than 0. 999. The detection limitr were in the range from 0. 21 te2.47 'g/L foe direct injection, and the average reccvvries ranged from 81. 0% to 119% with the relativv standard deviations lessthan 10% . For extraction and ccnccntration method , the method detection limitr of the target ccmpounds were in the range from 0.002 2 to 0.004 3 'g/L, and the average recoveries ranged from 71.5% to 115% with the relative standard deviations less than15% . This method is simple and fast, and itr precision and accuracy can meet the demands of determination of pyrethriod prsticideand oraanic phosphorus pesticide in water.Key words : UPLC-MS/MS ； Pyrethriod pesticide ； Oraanic phosphorous pesticide农药在现代化农业中必不可少,有机磷、拟除 虫菊酯和氨基甲酸酯类农药是目前使用量最大的 3类农药，它们普遍具有高效、广谱、低毒、低残留等特点'1（,在农业生产中被广泛应用'_3（。

分光光度法测定生活饮用水中六价铬的方法验证■ 胡 艳（四川省泸州生态环境监测中心站）摘 要：本文采用《生活饮用水标准检验方法 第6部分：金属和类金属指标》（GB/T 5750.6—2023）中二苯碳酰二肼分光光度法对生活饮用水中六价铬的方法进行验证研究，验证内容主要包括标准曲线线性关系、方法检出限、测定下限、准确度、精密度等方面，并对以上性能指标的测定结果进行分析，结果表明：标准曲线相关系数为0.9999；检出限为0.0007 mg/ L；测定下限为0.0021 mg/L；精密度为0.3%~0.8%；加标回收率为95%~102%，所有性能指标验证结果均能满足方法标准要求，本实验室具备采用二苯碳酰二肼分光光度法测定生活饮用水中六价铬的能力。

关键词：六价铬，分光光度法，方法验证DOI编码：10.3969/j.issn.1002-5944.2024.03.035Validation of Determination of Hexavalent Chromium in Drinking Waterby Spectrophotometry MethodHU Yan（Sichuan Luzhou Ecological Environment Monitoring Center Station）Abstract:In this paper, the validation study of hexavalent chromium determination in drinking water by diphenylcarbazide spectrophotometry is conducted, which is expounded in GB/T 5750.6—2023, Standard examination methods for drinking water—Part 6: Metal and metalloid indices. The verifi cation content mainly includes linearity calibration curve, method detection limit, lower limit of determination, accuracy, precision and other aspects, and the verifi cation results are analyzed in the paper. The results show that the correlation coeffi cient of the standard curve was 0.9999, the method detection limit was 0.0007 mg/L, the lower limit of determination was 0.0021 mg/L, the precision was 0.3%~0.8%, the add standard recovery rate was 95%~102%, and the validation results of all performance indicators meet the requirements of the standard, which means the laboratory has the ability to determine hexavalent chromium in drinking water by diphenylcarbazide spectrophotometry method.Keywords: hexavalent chromium, spectrophotometry, method validation自然界中的铬主要以三价铬和六价铬两种价态存在，在水环境中二者在特定条件下能够相互转化，三价铬较稳定、毒性小，六价铬氧化性强、毒性大，长期饮用被六价铬污染的生活饮用水，可能会对人体产生“三致”（致癌、致畸和致突变）危害，因此，六价铬是水质监测的重点项目之一。

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生态毒理学报Asian Journal of Ecotoxicology第18卷第3期2023年6月V ol.18,No.3Jun.2023㊀㊀基金项目:国家自然科学基金资助项目(42007392,42077404,42222711)㊀㊀第一作者:蔡凤珊(1992 ),女,博士研究生,研究方向为环境与健康,E -mail:********************㊀㊀*通信作者(Corresponding author ),E -mail:*****************DOI:10.7524/AJE.1673-5897.20221126002蔡凤珊,李嘉璐,李敏,等.广州市新生儿胎发中金属元素水平及对新生儿出生体质量影响的初步研究[J].生态毒理学报,2023,18(3):271-284Cai F S,Li J L,Li M,et al.A preliminary study on levels of metal(loid)s in infant hair and associated influence on birth weight of neonates in Guang -zhou [J].Asian Journal of Ecotoxicology,2023,18(3):271-284(in Chinese)广州市新生儿胎发中金属元素水平及对新生儿出生体质量影响的初步研究蔡凤珊1,2,4,李嘉璐2,3,李敏2,严骁2,3,*,唐斌2,郑晶1,2,3,麦碧娴11.中国科学院广州地球化学研究所有机地球化学国家重点实验室,广东省资源环境利用与保护重点实验室,广州5106402.生态环境部华南环境科学研究所新污染物研究团队,国家环境保护环境污染健康风险评价重点实验室,广州5105303.贵州医科大学公共卫生与健康学院,环境污染与疾病监控教育部重点实验室,贵阳5500004.中国科学院大学,北京100049收稿日期:2022-11-26㊀㊀录用日期:2023-02-10摘要:珠三角地区环境中的重金属污染较严重,母婴等敏感人群健康容易受到有毒金属暴露或必需元素失衡的不良影响,相关的暴露水平监测数据和风险因素研究仍非常有限㊂本研究采集了珠三角地区广州市健康新生儿的胎发样本和配对的母发样本,分析了10种金属元素(Zn ㊁Cu ㊁Se ㊁Mn ㊁Co ㊁V ㊁As ㊁Cd ㊁Pb 和Sb)含量,通过问卷调查收集孕产妇的人口学特征和孕期生活习惯信息,以了解胎儿宫内金属元素暴露情况和潜在影响因素㊂结果表明,广州市新生儿胎发中Mn ㊁Co ㊁V 和As 的含量高于国外报道水平,与广州市的大气污染和孕妇饮食习惯有关㊂大部分胎发的Se 与有毒金属的物质的量比值>1,提示宫内暴露于有毒金属对胎儿的毒性影响可能因为Se 的解毒作用而得到缓解㊂孕前补充叶酸和复合维生素等营养素可以提高母体和胎儿Se 水平,有助于维持Se 对有毒金属的解毒能力㊂BKMR 混合模型模拟结果表明,金属混合物产前暴露对新生儿出生体质量具有负面的联合影响,其中有毒金属As ㊁Pb ㊁V 和Sb 是与出生体质量负相关的重要因素㊂关键词:金属元素;胎发;影响因素;宫内暴露;出生体质量文章编号:1673-5897(2023)3-271-14㊀㊀中图分类号:X171.5㊀㊀文献标识码:AA Preliminary Study on Levels of Metal (loid )s in Infant Hair and Associ-ated Influence on Birth Weight of Neonates in GuangzhouCai Fengshan 1,2,4,Li Jialu 2,3,Li Min 2,Yan Xiao 2,3,*,Tang Bin 2,Zheng Jing 1,2,3,Mai Bixian 11.State Key Laboratory of Organic Geochemistry,Guangdong Provincial Key Laboratory of Environmental Protection and Resources Utilization,Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510640,China2.State Environmental Protection Key Laboratory of Environmental Pollution Health Risk Assessment,Research Group of Emerging Contaminants,South China Institute of Environmental Sciences,Ministry of Ecology and Environment,Guangzhou 510530,China3.School of Public Health,The Key Laboratory of Environmental Pollution Monitoring and Disease Control,Ministry of Education,Guizhou Medical University,Guiyang 550000,China4.University of Chinese Academy of Sciences,Beijing 100049,ChinaReceived 26November 2022㊀㊀accepted 10February 2023272㊀生态毒理学报第18卷Abstract:The contamination of heavy metals is serious in the Pearl River Delta.Exposure to toxic metal(loid)s or the unbalanced levels of essential elements would cause negative effects on humans,especially for vulnerable groups like pregnant mothers and fetuses.However,data on relevant exposure monitoring and the risk factors re-main limited so far.In this study,ten metal(loid)s(i.e.Zn,Cu,Se,Mn,Co,V,As,Cd,Pb,and Sb)in hair samples of paired neonates and mothers were analyzed.Maternal demographic characteristics and living habits during preg-nancy were collected through questionnaires.The results showed that the levels of Mn,Co,V,and As in infant hair of the neonates in Guangzhou were higher than those reported from abroad,which may be explained by the air pol-lution and the maternal dietary intake in Guangzhou.The molar ratios of Se to toxic metals in most infant hair were higher than one,indicating that the detoxification of Se could reduce the adverse effects of in utero exposure to these toxic metals on the neonates.Prenatal supplementation with folic acid and multivitamins could increase mater-nal and fetal Se levels and help to maintain the detoxification of Se on toxic metals.The results of BKMR model showed that the prenatal exposure to metal mixture had a negative joint effect on the fetal birth weight,with As, Pb,V,and Sb as the important associated factors.Keywords:metal(loid)s;infant hair;related factors;in utero exposure;birth weight㊀㊀随着全球化学品产量不断增加,暴露于包括金属元素在内的环境污染物是一个日益受到广泛关注的公共卫生问题㊂一些金属元素是人体某些生物功能所必需的关键元素,如锌(zinc,Zn)㊁铜(copper, Cu)㊁锰(manganese,Mn)㊁硒(selenium,Se)和钴(cobalt, Co)在维持细胞稳态中起着重要作用[1],必需元素的缺乏或过量会导致生物功能障碍[2]㊂另一些金属元素则可以改变细胞内稳态,即使在微量浓度下也有毒性效应[3],被称为有毒金属㊂如砷(arsenic,As)㊁镉(cadmium,Cd)㊁铅(lead,Pb)和钒(vanadium,V)可以取代或模拟必需金属,破坏细胞过程[2-3],并且可以穿过胎盘,引起生命早期暴露[4]㊂大量研究表明,孕妇早产流产㊁胎儿生长缓慢和新生儿出生低体质量等不良妊娠结局与人体必需微量元素缺乏和有毒金属过量有关[5-7]㊂珠江三角洲(珠三角)地区是世界上最大的城市群之一㊂工业化和城市化的发展增加了能源消耗和人为排放,导致城市土壤㊁道路灰尘㊁动植物和大气中的金属污染[8-10],严重威胁着当地居民的健康㊂已有研究对广东省重金属重污染地区如韶关市矿区[11]和汕头市贵屿镇电子垃圾拆解区[12]的新生儿脐带血重金属水平进行了报道,均发现了重金属超标情况㊂一项对广州市普通人群的231例新生儿金属元素水平监测结果显示,脐血Pb的平均水平为(28.2ʃ1.76)μg㊃L-1,脐血Cd浓度<0.5μg㊃L-1占84.4%,ȡ0.5μg㊃L-1占15.6%,脐血Pb和Cd水平均在国家标准范围内[13]㊂目前针对珠三角地区母婴人群的金属元素水平监测数据仍非常有限,有毒金属对早期生命发育的潜在风险和累积影响仍未可知㊂胎发和胎粪是直接量化胎儿宫内暴露的重要生物材料,然而胎粪中痕量有毒金属(如Pb和Cd)的检出率低[14],限制了其作为产前暴露指示材料在一般母婴人群的应用㊂在发育24~28周之间,胎儿毛囊进入生长期,随后进入静止期,然后脱落进入第二个生命周期[15]㊂因此,足月新生儿的胎发提供了孕晚期的金属元素累积暴露信息㊂胎发已应用于有毒金属产前暴露的生物监测,包括汞(mercury,Hg)㊁Pb㊁Mn和As[16-18]㊂本研究收集了珠三角地区广州市健康新生儿的胎发样本,以了解胎儿宫内金属元素暴露情况和潜在风险;采集了配对的母发样本用于分析母体和胎儿金属元素含量相关性,探讨母婴人口学特征和孕期生活习惯对胎发金属元素水平的影响;并初步评估了金属混合暴露对新生儿出生体格的影响㊂本研究结果为评估普通母婴人群金属元素暴露及风险奠定基础㊂1㊀材料与方法(Materials and methods)1.1㊀研究对象从2020年6月 2021年6月期间在广州市中山大学第六附属医院招募孕产妇志愿者㊂孕产妇志愿者纳入标准如下:(1)在生产前在广州固定居住2年以上;(2)>20周岁且<50周岁;(3)孕周ȡ37周;(4)新生儿Apgar评分为9~10分㊂排除标准如下:(1)患有严重的妊娠合并症㊁遗传性疾病㊁传染病或精神疾病;(2)其配偶有家族遗传性疾病史;(3)新生儿有严重出生缺陷㊂该研究得到中山大学第六附属医院伦理委员会审查的批准(批准号:2019ZSLYC-217),第3期蔡凤珊等:广州市新生儿胎发中金属元素水平及对新生儿出生体质量影响的初步研究273㊀所有参与者均签署知情同意书㊂1.2㊀样品采集和资料收集新生儿胎发的采集在其出生2d内完成㊂在新生儿进行头发清洁后,使用干净的电动剃刀在贴近头皮处剃掉头发,并用干净的纤维纸包裹后放入密封袋中,于-20ħ冰箱中保存㊂本研究采用自行编制的问卷对孕产妇孕期的生活和饮食习惯进行调查㊂通过培训的调查员在产妇分娩后进行问卷调查,问卷内容包括:产妇年龄㊁产次㊁教育水平㊁被动吸烟情况㊁孕期食用海产品情况㊁饮用水源和补充叶酸情况等㊂通过医院病历系统收集产妇产前健康状况,包括身高㊁孕前BMI㊁孕期增重和妊娠并发症情况等,以及新生儿出生情况,包括性别㊁胎龄㊁出生体质量㊁出生身长和出生头围等信息㊂1.3㊀实验仪器与材料实验仪器:电感耦合等离子体质谱(PerkinElmer NexlON2000,美国),水浴锅(智诚分析仪器制造,中国),氮吹仪(Organomation N-EV AP-24,美国),涡旋振荡器(Troemner JL-D,美国),离心机(Sigma1-14K,德国;Centrifuge5424R,德国),Milli-Q超纯水系统(Merck,德国)㊂实验材料:头发标准物质(GBW07601a,中国),金属元素混合标准品(AccuStandard,美国),标准品锑(antimony,Sb)㊁As㊁Se(国家有色金属及电子材料分析测试中心,中国),内校正标准品(国家有色金属及电子材料分析测试中心,中国),硝酸(69%,ppt 级),30%双氧水,正己烷㊁二氯甲烷㊁丙酮,1mL无菌连针注射器,0.45μm亲水PTFE针式滤器,15 mL离心管(安谱实验室技术(上海)有限公司,中国),称量纸(上海伯奥生物科技,中国),金标纯水(Fisher,美国),50mL特氟龙管(Oak Ridge,美国)㊂1.4㊀金属元素分析10种目标金属元素为Zn㊁Cu㊁Se㊁Mn㊁Co㊁V㊁As㊁Cd㊁Pb和Sb㊂将胎发样品置于洁净锥形瓶中,加入Milli-Q超纯水没过胎发,置于40ħ水浴摇床中振荡1h进行清洗,重复2遍清洗步骤后,进行冷冻干燥;冻干胎发称量记录,置于50mL特氟龙试管中,加入3mL硝酸/过氧化氢(1ʒ1,VʒV),置于60ħ水浴中消解2h后,用纯水定容至10mL,通过0.45μm滤膜转移至离心管中;取1mL过滤后的样品稀释至10mL,使用电感耦合等离子体质进行上机检测㊂仪器分析方法参考课题组以往分析方法[19]㊂每批头发样本准备了有证标准物质(Certified reference material,CRM)和程序空白㊂CRM中金属元素的回收率在75%~120%㊂金属元素Zn㊁Cu㊁Se㊁Mn㊁Co㊁V㊁As㊁Cd㊁Pb和Sb的LOD分别为0.004㊁0.001㊁0.379㊁0.009㊁0.001㊁0.004㊁0.034㊁0.001㊁0.012和0.007ng㊃g-1,标准曲线的相关系数均>0.999㊂1.5㊀统计学分析统计学分析采用SPSS26(IBM,美国)软件操作㊂描述分析中,计量资料用均数ʃ标准差(x ʃS)表示,计数资料用例数㊁构成比(n,%)表示㊂采用卡方检验分析胎儿性别对胎发金属元素浓度的影响㊂金属元素浓度对数转换后,采用皮尔逊相关分析法分析胎发金属元素之间以及胎发和母发金属元素的相关关系,相关分析通过孕产妇的人口学特征和生活方式等混杂因素进行调整㊂配对的母发样品是从贴近产妇头皮处剪取0~9cm的头发,并使用陶瓷剪刀将头发分成3个3cm发段,用以表征孕早(6~9 cm)㊁中(3~6cm)㊁晚(0~3cm)期及整个孕期(0~9 cm)母体金属元素的暴露情况(相关数据未发表)㊂采用Se与重金属的物质的量比值来评估胎儿重金属暴露的潜在风险[19]㊂采用多元线性回归模型评估胎发金属元素浓度和孕产妇的人口学特征和生活方式的关系㊂设定P<0.05为具有显著的统计学意义㊂采用INTERGROWTH-21st Project新生儿体型计算器,计算出生体质量-Z评分(birth weight Z score,BWZ)㊁出生体长-Z评分(birth length Z score, BLZ)和出生头围-Z评分(head circumference Z score, HCZ)㊂考虑到金属混合物和出生体型指标之间可能存在非加性和非线性关联,因此采用贝叶斯核机器回归模型(Bayesian kernel machine regression,BK-MR)[20]检验金属混合物暴露和每个出生体型指标之间的总体关联,以及每个污染物的相对贡献,使用高斯核函数对模型进行了10000次迭代㊂BKMR混合模型根据孕妇年龄㊁孕前体质量指数(BMI)(kg㊃m-2)㊁胎次和母亲孕期增重(kg)进行调整㊂BKMR 模型使用R软件(4.1.0版本)进行,应用 BKMR (0.2.2版本)的R包实现㊂2㊀结果与讨论(Results and discussion)2.1㊀母婴一般人口学特征表1描述了新生儿出生结局和产妇人口学特征㊂纳入研究的新生儿(n=42)胎龄为(269ʃ10)d,男胎占62%㊂与新生儿配对产妇(n=41)的年龄为(30ʃ4)岁,孕前BMI为(20.9ʃ2.63)kg㊃m-2,孕期增重(13.2ʃ3.79)kg,初产妇占56%,大专以上学历的孕妇274㊀生态毒理学报第18卷表1㊀母婴一般人口学信息Table1㊀Demographic characteristics of thestudy population人口学特征Characteristics 平均值ʃ标准差MeanʃSD计数(%)n(%)新生儿Neonates(n=42)出生胎龄/d Gestational age/d269ʃ10出生体质量/kg Birth weight/kg 3.05ʃ1.33出生身长/cm Birth length/cm49.2ʃ4.43出生头围/cm Head circumference/cm32.6ʃ1.18性别Infant sex男Male26(62%)女Female16(38%)产妇Maternal(n=41)产妇年龄/dMaternal age/d30ʃ4产妇孕前BMI/(kg㊃m-2)Pre-pregnancy BMI/(kg㊃m-2)20.9ʃ2.63孕期增重/kgPregnancy weight gain/kg13.2ʃ3.79产妇文化程度Maternal education大专以下College degree or below18(44%)大专及以上Minimum bachelor23(56%)产妇产次Parity123(56%)>118(44%)产妇孕期补充叶酸时间Folic acid supplementation备孕和怀孕期间Before pregnancy19(46%)仅怀孕期间After pregnancy22(54%)家庭饮用水类型Drinking water自来水Tap water19(46%)净化自来水/桶装水/瓶装水Purified water22(54%)孕期食用水产品频率Aquatic products consumption0~3d㊃周-1(d㊃week-1)34(83%) 4~7d㊃周-1(d㊃week-1)7(17%)孕期主动或被动吸烟Passive smoking during pregnancy否No34(83%)是Yes7(17%)约占56%㊂大多数孕产妇在孕期食用水产品频次为0~3d㊃周-1(83%),不存在主动或被动吸烟(83%)㊂约46%的孕妇在怀孕前服用叶酸补充剂,约54%的孕妇孕期饮用水经过净化处理㊂2.2㊀胎发中金属元素的浓度在所有胎发样品中均检出目标金属元素,其中位值含量由高到低排序依次是:Zn(203μg㊃g-1)>Cu (7.61μg㊃g-1)>Se(1.10μg㊃g-1)>Mn(0.87μg㊃g-1)>Pb (0.33μg㊃g-1)>Co(0.13μg㊃g-1)>As(0.083μg㊃g-1)> V(0.066μg㊃g-1)>Sb(0.048μg㊃g-1)>Cd(0.012μg㊃g-1)㊂胎发金属元素水平与胎儿性别无关(P>0.05),因此将整体(n=42)讨论胎发金属元素水平㊂目前针对胎发金属元素水平的参考剂量和建议暴露限值尚未明确,与不同胎发金属元素水平相关的直接健康风险指标尚不清楚㊂为了评价胎儿暴露于金属元素的潜在风险,比较了不同国家报道的胎发金属元素水平(表2)㊂新生儿的胎发Zn㊁Cu和Se含量平均值(范围)分别为215(121~347)㊁10.4(5.34~61.1)和1.62(0.30~8.18)μg㊃g-1,与美国[21]㊁加拿大[22]㊁伊朗[23]和巴勒斯坦[24]的报道水平相似,稍高于德国[25]和英国[26]的报道水平㊂胎发Mn㊁Co和V含量平均值分别为3.21(0.14~42.5)㊁0.56(0.007~8.65)和0.18 (0.011~1.96)μg㊃g-1,高于巴勒斯坦[5,24]㊁伊朗[23]和西班牙[27]的报道水平㊂对于有毒金属元素,胎发As 含量平均值为0.15(0.017~0.71)μg㊃g-1,高于巴勒斯坦[5,24]和伊朗[23]的报道水平,低于孟加拉国[28]的报道水平㊂胎发Pb㊁Cd和Sb含量平均值分别为1.16 (0.083~11.3)㊁0.032(0.001~0.280)和0.085(0.015 ~0.63)μg㊃g-1,低于美国[21]㊁英国[26]㊁德国[25]和土耳其[18,29]的报道水平,稍高于巴勒斯坦[5,24]的报道水平㊂总的来说,相对其他国家的报道水平,广州市新生儿胎发中Mn㊁Co㊁V和As的含量偏高㊂城市垃圾焚烧㊁化石燃料燃烧和汽车尾气排放造成的空气污染是导致Mn㊁Co和V环境暴露的主要原因[30-32]㊂室内空气中Mn㊁Co和V水平升高可能与机动车辆灰尘的自然沉降有关㊂一项研究发现,相对于远离主干道居住人群,居住在主干道附近的人群体内的细颗粒物(PM2.5)结合的Mn㊁Co和V 的浓度更高[33]㊂根据‘中国统计年鉴2022“‘广东省统计年鉴2022“,2021年中国私家车数量为26200万辆[34],其中广州市私家车数量为320万辆[35],占全国私家车数量约1.2%[34]㊂推测交通排放等造成的大气金属污染可能会增加城市居民的重金属负担,第3期蔡凤珊等:广州市新生儿胎发中金属元素水平及对新生儿出生体质量影响的初步研究275㊀表2㊀新生儿胎发中10种金属元素水平及比较Table2㊀Metal(loid)concentrations comparison of infant hair in different countries(μg㊃g-1)金属元素Metal(loid)s国家Country平均值Mean中位值Median最小值Min最大值Max参考文献ReferencesZn中国China215203121347本研究This study 美国USA225-222229[21]英国UK147-88.0239[26]加拿大Canada-221--[22]德国Germany116---[25]伊朗Iran228---[23]巴勒斯坦Palestine2242040.903340[24]Cu中国China10.47.61 5.3461.1本研究This study 美国USA10.9-10.511.3[21]加拿大Canada-11.2--[22]德国Germany13.4---[25]英国UK 6.70- 4.3014.0[26]伊朗Iran14.3---[23]巴勒斯坦Palestine41.77.680.0616300[24]Se中国China 1.62 1.100.308.18本研究This study 英国UK0.63-0.10 3.00[26]巴勒斯坦Palestine 1.030.980.22 4.38[24]巴勒斯坦Palestine-0.257(2011)1.01(2015)0.465(2016)1.690(2018 2019)--[5]Mn中国China伊朗Iran孟加拉国Bangladesh巴勒斯坦Palestine西班牙Spain3.210.870.1442.51.13---14.08.40 3.4018.613.09.50 4.2017.80.930.310.0420.0-0.310.02 1.23本研究This study[23][28][24][27]Co中国China0.560.130.0078.65本研究This study 伊朗Iran0.073---[23]巴勒斯坦Palestine0.080.020.028.70[24]巴勒斯坦Palestine-0.053(2011)0.060(2015)0.030(2016)0.150(2018 2019)--[5]V中国China0.180.0660.011 1.96本研究This study 伊朗Iran0.088---[23]巴勒斯坦Palestine0.050.010n.d.11.7[24]巴勒斯坦Palestine-0.010(2011)0.014(2015)0.012(2016)0.021(2018 2019)--[5]276㊀生态毒理学报第18卷续表2金属元素Metal(loid)s国家Country平均值Mean中位值Median最小值Min最大值Max参考文献ReferencesPb中国China 1.160.330.08311.3本研究This study 美国USA13.913.013.114.7[21]德国Germany 2.70---[25]英国UK 4.56- 1.5010.0[26]伊朗Iran 2.71---[23]土耳其Turkey 2.27- 1.018.01[29]土耳其Turkey- 2.450.2615.8[18]巴勒斯坦Palestine0.510.230.0415.5[24]As中国China0.150.0830.0170.71本研究This study 伊朗Iran0.024---[23]孟加拉国Bangladesh0.600.20--[28]巴勒斯坦Palestine0.050.01n.d.8.34[24]巴勒斯坦Palestine-0.062(2011)0.015(2015)0.016(2016)0.010(2018 2019)--[5]Sb 中国China0.0850.0480.0150.63本研究This study 英国UK0.8260.3600.011 3.75[26]伊朗Iran0.044---[23]Cd中国China0.0320.0120.0010.280本研究This study 德国Germany0.080---[25]英国UK0.57[26]伊朗Iran0.157---[23]土耳其Turkey0.070-0.0100.220[29]土耳其Turkey-0.0720.0100.872[18]巴勒斯坦Palestine-0.036(2011)0.009(2015)0.014(2016)0.007(2018 2019)--[5]导致广州市新生儿胎发中Mn㊁Co和V的含量偏高㊂一项针对广州市普通居民的健康调查研究发现,广州居民尿液中As的浓度最高(中位值为41.0μg㊃L-1),高于我国国家人体生物监测中心报道的中位数(19.0μg㊃L-1)[36],表明广州市居民的As暴露水平普遍较高㊂这与当地人的饮食习惯密切相关, 2021年广东省人均水产品摄入量高达27.6kg[35],约为全国人均水平(14.2kg)的2倍[34]㊂研究表明经常食用水产品,尤其海鲜的孕妇有更高的尿As浓度[37]㊂此外,一项针对珠江三角洲地区大气As沉降污染研究表明,近5年来珠江三角洲地区大气As 排放量不断增加,广州市As总沉降通量比中国平均水平高42.1%,远高于发达国家[10]㊂因此广州市新生儿胎发中As含量偏高可能与广州市的大气As 污染和孕妇饮食习惯有关㊂2.3㊀胎发中金属元素的相互作用为分析金属元素之间可能的相互作用,图1展示了胎发金属元素浓度之间的相关关系㊂研究发现,除了Se,其余9种金属元素含量之间均存在正相关关系(r>0.50,P<0.05),表明这些金属元素的暴露来源和毒代动力学相似㊂极少液体能够通过羊膜返回母体内循环,因此高溶解度的金属元素被困在胎儿和羊水之间[38]㊂胎儿通过排泄向羊水释放的金属元素会再次通过吸入进入胎儿,而持续暴露于羊水有助于金属元素扩散到胎发基质[39]㊂因此胎发完整地保留了胎儿内循环和羊水中的金属元素,由此这些金属元素水平呈现较高的正相关关系㊂第3期蔡凤珊等:广州市新生儿胎发中金属元素水平及对新生儿出生体质量影响的初步研究277㊀图1㊀胎发中金属元素含量(对数转换后)的皮尔逊相关关系Fig.1㊀Pearson correlation for log -transformed metal concentrations in infant hair㊀㊀胎发Se 仅与Zn ㊁As ㊁Sb ㊁Pb 和V 存在正相关关系(r =0.41~0.71,P <0.05),表明这些金属元素与Se 可能存在相似的毒代动力学过程㊂Se 是一种强大的抗氧化剂,其可以通过结合重金属并降低其在生物体内的生物利用率来拮抗重金属的毒性㊂Se 与某些重金属的物质的量比被认为是一个重要的重金属风险评估指标,常被用来代表个体解毒能力[40]㊂Se 和重金属结合形成的惰性复合物在生物学上无毒,Se 与重金属的物质的量比ɤ1被认为是出现不良反应的阈值[41]㊂考虑到Se 与重金属的相关作用,论文采用Se/单个金属的物质的量比来初步评估有毒金属对胎儿的潜在健康影响,并尝试用Se/金属混合物的物质的量比来初步评估这些有毒金属的总体风险[19]㊂图2显示所有新生儿胎发的Se/As ㊁Se/Sb 和Se/Cd 物质的量比>1,绝大多数新生儿胎发(98%)的Se/V 物质的量比>1,大部分胎发(88%)的Se/Pb 物质的量比>1㊂结果表明宫内暴露于这些有毒金属对胎儿的毒性影响可能因为Se 的解毒作用而得到了部分缓解㊂但19.5%的胎发中Se/金属混合物物质的量比<1(图2),表明胎儿仍然存在这些有毒金属共暴露的潜在毒性风险㊂2.4㊀胎发中金属元素含量的影响因素除了与羊水持续和稳定的交换,胎发还可以通过胎盘传递给毛囊的生发细胞带来母体的金属元素,胎发中的这些金属元素水平总体上受母体内金属元素水平的影响㊂通过配对分段母发来表征母体不同孕期金属元素暴露情况,并进一步分析胎发与母发浓度的关系及其他影响因素㊂表3展示了配对胎发和母亲头发段中金属元素的相关分析,结果显示未进行混杂因素调整前,仅有Se (r =0.444,P <0.01)和Cd(r =-0.335,P <0.05)在配对胎发和分段母发之间具有相关关系,在混杂因素调整后,配对胎发和分段母发(3~6cm,r =0.492,P <0.05)以及全段母发(0~9cm,r =0.560,P <0.01)的Se 具有正相关关系,胎发中Mn 含量与母发(0~3cm)Mn 含量具有正相关关系(r =0.516,P <0.05)㊂配对胎发和母发之间金属元素含量的弱相关性,可能受到胎盘屏障功能的影响㊂例如,金属硫蛋白能与Cd 结合形成蛋白复合物,Se 能够与Cd 形成Se -Cd 复合物,2种途径均可把Cd 滞留于胎盘组织中[42]㊂Sakamoto 等[4]研究发现,人胎盘Cd 水平是脐带的59倍㊂金属硫蛋白也可以与Pb 结合,然而Pb 仍可以通过简单扩散自由地通过胎盘组织,因此胎盘屏障并不能有效阻隔Pb 的母胎传递㊂例如,母体Cu 含量受到机体的严格调控㊂Cu 被分子伴侣蛋白隔离,在不急需时储存以备将来使用,并通过载体介质转移[43]㊂当胎盘Cu 水平过高时,Cu 转运蛋白表达,并将Cu 转运回母体循环[43]㊂Sakamoto 等[4]的研究表明,母血Cu 与脐带血Cu 水平并无显著相关性㊂此外,胎盘向胎儿转移各种金属元素的能力可能随孕期而变化[44],胎盘转运蛋白在胎盘中的表达因胎龄而异[45],因此可能表现出不同孕期母胎金278㊀生态毒理学报第18卷属元素相关关系的差异㊂母婴人口学信息调整后,胎发和母发金属元素水平的相关系数变化显著,表明人口学特征对胎发中金属元素水平的调节作用明显㊂运用多元线性回归分析探讨胎发中金属元素水平的人口学影响因素,表4展示了回归方程具有显著相关性的结果㊂图2㊀胎发中Se/金属的物质的量比注:x为对数转换的金属元素含量(μmol㊃kg-1),y为对数转换的Se/金属物质的量比,红色标记为Se/金属物质的量比ɤ1的个体,金属混合物包括As,Sb,Cd,Pb和V㊂Fig.2㊀Se/certain heavy metal molar ratio in infant hairNote:The scatter plot of logarithm of levels of certain heavy metal(μmol㊃kg-1)and log(Se/certain heavy metal molar ratio)in hair;individuals with Se/metal ratiosɤ1are marked in red;metal mixture include As,Sb,Cd,Pb and V.第3期蔡凤珊等:广州市新生儿胎发中金属元素水平及对新生儿出生体质量影响的初步研究279㊀表3㊀配对胎发和母亲头发段中金属元素的相关分析Table3㊀The pairwise comparison of metal(loid)s in paired infant and maternal hair segments金属元素Metal(loid)s 胎发vs.母发(0~3cm)Infant hair vs.maternalsegment(0~3cm)胎发vs.母发(3~6cm)Infant hair vs.maternalsegment(3~6cm)胎发vs.母发(6~9cm)Infant hair vs.maternalsegment(6~9cm)胎发vs.母发(0~9cm)Infant hair vs.maternalsegment(0~9cm)r a Adj.r b r a Adj.r b r a Adj.r b r a Adj.r bZn-0.034-0.2740.034-0.1740.083-0.1810.023-0.196Se0.0850.2890.444**0.492*0.0460.3200.2800.560**Mn0.2300.516*0.033-0.0460.0840.1180.1560.246Cu0.0720.1940.0320.1370.1620.3400.0900.225V0.0790.176-0.145-0.1100.143-0.0460.041-0.024Co0.2500.373-0.142-0.2140.0380.0170.0490.014As0.1340.1630.1430.1910.2390.4100.2300.356Cd-0.249-0.181-0.233-0.100-0.335*-0.053-0.234-0.100Sb0.230-0.2520.189-0.0760.131-0.0910.207-0.154Pb-0.0720.159-0.172-0.093-0.1800.130-0.1240.056注:**在0.01级别(双尾),相关性显著;*在0.05级别(双尾),相关性显著;a皮尔逊相关系数;b偏相关分析系数,控制变量包括新生儿性别㊁胎龄㊁产妇年龄㊁产妇孕前BMI㊁产妇孕期增重㊁产妇胎次㊁产妇教育水平㊁孕期是否被动吸烟㊁孕期水产品摄入㊁孕期饮用水类型和是否孕前补充叶酸㊂Note:**Correlation is significant at the0.01level(2-tailed);*Correlation is significant at the0.05level(2-tailed);a Pearson-correlation coefficients;b Partial correlation was adjusted for infant gender,gestational age,maternal age,pre-pregnancy body mass index,pregnancy weight gain,parity,maternal education,passive smoking during pregnancy,aquatic products consumption,drinking water and folic acid supplementation.表4㊀胎发中金属元素含量的影响因素回归模型Table4㊀Results of multiple linear regression models of factors influencing metal(loid)s concentrations in infant hair金属元素Metal(loid)s 影响因素Factors标准化系数Standardized coefficientβ(95%CI)Adj.βSig R2Adj.R2Zn常量Constant 2.59(2.31,2.87)<0.0010.1340.102孕前BMI Pre-pregnancy BMI-0.014(-0.027,0)-0.3670.051Mn常量Constant0.402(0.089,0.715)0.0140.3150.263母亲头发(0~3cm)Mn含量Maternal hair Mn(0~3cm)0.995(0.352,1.64)0.5290.004孕期被动吸烟Passive smoking during pregnancy否No-0.560(-1.12,0.001)-0.3450.050是Yes(ref)Se常量Constant0.419(0.148,0.690)0.004母亲头发(3~6cm)Se含量Maternal hair Se(3~6cm)1.16(0.365,1.95)0.3840.0060.3820.305胎次Parity>10.189(-0.020,0.399)0.1020.075=1(ref)补充叶酸时期Folic acid supplementation孕前Before pregnancy0.233(0.441,0.025)0.1010.029孕后After pregnancy(ref)Sb常量Constant-1.12(-1.28,-0.969)<0.0010.1780.147补充叶酸时期Folic acid supplementation孕前Before pregnancy-0.275(-0.509,-0.041)-0.4220.023孕后After pregnancy(ref)注:多元回归模型的控制变量包括新生儿性别㊁胎龄㊁产妇年龄㊁产妇孕前BMI㊁产妇孕期增重㊁产妇胎次㊁产妇教育水平㊁孕期是否被动吸烟㊁孕期水产品摄入㊁孕期饮用水类型和是否孕前补充叶酸㊂Note:Multiple linear regression models were adjusted for infant gender,gestational age,maternal age,pre-pregnancy BMI,pregnancy weight gain,parity, maternal education,passive smoking during pregnancy,aquatic products consumption,drinking water and folic acid supplementation.280㊀生态毒理学报第18卷结果表明,备孕期间补充叶酸,可以显著增加胎发Se 含量(0.233[0.441,0.025],P =0.029)和减少Sb 含量(-0.275[-0.509,-0.041],P =0.023)㊂此外,女性备孕补充叶酸的同时也会补充其他营养素,如复合维生素,研究表明补充复合维生素的孕妇Se 含量较高[37]㊂由此表明,孕前补充叶酸㊁复合维生素等营养素可以增加母体和胎儿Se 水平,有助于持续合成Se 依赖性酶来维持Se 的解毒能力,从而缓解重金属的潜在毒性[40]㊂本研究中胎发Mn 含量与母发(0~3cm)Mn 含量显著相关(0.995[0.352,1.64],P=0.004),胎发Se 含量与母发(3~6cm)Se 含量显著相关(1.16[0.365,1.95],P =0.006)㊂以往研究发现母图3㊀BKMR 模型研究胎发中金属元素水平与新生儿出生体质量的关系注:(a)金属混合物暴露对出生体质量-Z 评分的累积效应及95%置信区间;(b)胎发金属元素与出生体质量Z 评分的BKMR 单变量暴露-反应函数,每个面板显示指定金属和出生体质量Z 评分之间的关联(95%置信区间),将所有其他元素设置为其中位数;(c)单个金属暴露对出生体质量-Z 评分的单独效应及95%置信区间,将所有其他元素固定在第25㊁50或75百分位数;(d)胎发金属元素与出生体质量Z 评分的BKMR 双变量暴露-反应函数,每个面板显示指定的金属(列)和出生体质量Z 评分之间的关联,将第2个金属(行)设置为其第10㊁50和90百分位数,并将所有其他元素设置为其中位数;BKMR 混合模型的控制变量包括新生儿性别㊁胎龄㊁产妇年龄㊁产妇孕前BMI ㊁产妇孕期增重和产妇胎次㊂Fig.3㊀Association between infant hair metal levels and birth weight by BKMR modelNote:(a)Estimated cumulative effects (with 95%credible intervals)of infant hair metal mixtures on birth weight Z -scores estimated by BKMR;(b)Exposure -response plots (95%credible intervals)for associations between birth weight Z -scores and Z scored concentrations of individual metals when all other metals are fixed at their median concentrations;(c)Estimated differences (95%credible intervals)in birth weight Z -scores for individual metals and all other metals are fixed at their 25th ,50th ,or 75th percentiles;(d)Bivariate Exposure -Response Functions for associations between each metal (columns)and birth weight Z -scores,setting a second metal (rows)to its 10th ,50th ,and 90th percentile and all other elements to their median;estimates are from BKMR models adjusted for infant gender,gestational age,maternal age,pre -pregnancy BMI,pregnancy weight gain and parity.。

·药物研发·高效液相色谱-串联质谱法检测泮托拉唑钠原料药中的水合肼赵会明 张振洋 樊华军［英格尔检测技术服务（上海）有限公司 上海 201100］摘要建立了泮托拉唑钠原料药中的基因毒性杂质水合肼的高效液相色谱-串联质谱（LC-MSMS）检测方法。

采用反相色谱，以水-乙腈（含0.1%甲酸）为流动相，梯度洗脱，流速0.5 mL/min，以ESI正离子多反应监测（MRM）模式进行质谱检测。

结果显示，水合肼的检测限和定量限可达到0.23、0.47 ng/mL，其在0.47~9.37 ng/mL浓度范围内线性关系良好（r=0.999 9），准确度试验中低、中、高浓度回收率均在81.6%~90.9%之间。

在3批次泮托拉唑钠原料药中均未检出水合肼。

关键词高效液相色谱-串联质谱法基因毒性杂质泮托拉唑钠水合肼痕量检测中图分类号：R917; O657 文献标志码：A 文章编号：1006-1533(2022)11-0072-04引用本文 赵会明, 张振洋, 樊华军. 高效液相色谱-串联质谱法检测泮托拉唑钠原料药中的水合肼[J]. 上海医药, 2022, 43(11): 72-75.Determination of hydrazine hydrate in pantoprazole sodium by high performance liquid chromatography-tandem mass spectrometryZHAO Huiming, ZHANG Zhenyang, FAN Huajun[ICAS Testing Technology Service (Shanghai) CO., LTD., Shanghai 201100, China]ABSTRACT To establish a high-performance liquid chromatography-tandem mass spectrometry (LC-MSMS) method for the determination of hydrazine hydrate in active pharmaceutical ingredient (API) pantoprazole sodium. HPLC was carried out by reverse chromatography using water-acetonitrile containing 0.1% formic acid as flow phase and gradient elution at a flow rate of 0.5 mL/min. Mass spectrometry was performed with multi-reaction monitoring (MRM) in positive ESI mode. The detection and quantitative limits of hydrazine hydrate reached 0.23, 0.47 ng/mL and hydrazine hydrate showed good linear relationship in the range of 0.47-9.37 ng/mL (r=0.999 9). The recoveries of samples at low, medium and high-level concentrations reached81.6% to 90.9% in the accuracy experiment. No hydrazine hydrate was detected in 3 batches of pantoprazole sodium.KEY WORDS HPLC-tandem mass spectrometry; genotoxic impurities; pantoprazole sodium; hydrazine hydrate; trace determination上消化道出血是近年的临床疾病中常见且多发的一种疾病，其临床表现为呕血、黑便等，如得不到及时有效治疗，可能引发失血性休克。

30 食品安全导刊 2010年10月刊管中预装入150mg无水硫酸镁和50mg PSA固相萃取填料。

DisQ u E ™基质分散样品制备试剂盒可提供快速、简便萃取海产品试样中PAH的方法。

样品进化后不需浓缩或溶剂置换，而且无需进行S PE固相萃取柱常用的平衡步骤，使用方便，省时省力。

ACQUITY ® UPLC H-Class系统ACQUITY U PLC ® H-Class系统是一套经过优化的先进系统，具有四元溶剂混合的灵活性和简易性，并带有一个流通针式进样器，可实现UPLC 分离的先进性能——高分离度、灵敏度和高通量，同时还保持了ACQUITY ® 系统所被公认的耐用性和可靠性。

选择ACQUITY UPLC ® H-Class，可以在面向未来的LC平台上继续运行现有的HPLC方法，并可实现向UPLC分离的无缝转换。

样品经过前处理后，即可使用集成系统工具和可靠的色谱柱工具ANALySIS & TEST 分析与检测利用DisQuE TM试剂盒和ACQUITY UPLC ®H-Class系统快速筛选海产品中的多环芳烃沃特世科技（上海）有限公司 供稿□近期发生的墨西哥湾漏油事件，引起了人们对该海域海产品质量的担忧。

石油中含有一类重要化合物——多环芳烃（PAH），会对海洋中的鱼、甲壳类动物以及软体动物造成污染，食用后将给人们带来潜在的健康风险。

为此，美国环境保护署（EPA）已将多环芳烃等16种化合物确定为重点污染物，路易斯安那州也公布了一项“安全响应与质量认证计划”，其中颁布了12种这类化合物的筛选标准。

为避免食用受污染的海产品，并尽可能减小对海产食品业的影响，需要采用一种快速筛选法对此类化合物进行分析；目前使用的H PLC或GC/MS方法至少需要30分钟的运行时间。

如何缩短检测时间、提高检测效率，已成为检测工作者关注的问题。

本文通过使用DisQu E ™基质分散样品制备试剂盒快速地对样品进行处理，并采用沃特世® ACQUITY UPLC ®H-Class系统对其进行液相色谱-荧光检测，在不到4分钟的时间即可完成对样品的PAH分析，可快速实现对海产品中的PAH污染物的筛选。