Determination of selected pesticides by GC with simultaneous detection by MS (NCI) and μ-ECD in fruit and vegetable matrices

A gas chromatography–mass spectrometry method in negative chemical ionization mode has been developed incorporating simultaneous detection using a micro-electron capture detector (μ-ECD) for the determination of pesticides in fruits and vegetables. This instrument configuration uses a three-way splitter device which divides the effluent from the analytical column between the two detectors with the split ratio 1:0.1 (MSD/μ-ECD) in each run. The μ-ECD was used for confirmation purposes. Validation of the method was performed on three matrices: tomato, apple, and orange. The ethyl acetate method was assayed; recovery studies were performed at 10 and 100 μg/kg. Recoveries between 70% and 120% were achieved and relative standard deviations lower than 20% (n = 5) were obtained for all pesticides and matrices studied. Limits of quantification lower than 10 μg/kg were obtained for 100% of pesticides in all of the matrices. Limits of quantification lower than 2.5 μg/kg were achieved for 77.8% of pesticides in the tomato and apple matrices, and for 72.2% of pesticides in the orange matrix. The method showed linear response in the concentration range tested (2.5–500 μg/kg) with correlation coefficients >0.99. Good repeatability and reproducibility results were obtained in all cases, with relative standard deviations lower than 16.7% and 20%, respectively. Finally, 20 incurred samples were analyzed using the proposed method. The simultaneous use of the two detectors was satisfactory for the analysis of these real samples. The total number of pesticides identified was 25. The number of samples which contained at least one pesticide was 15—this represented 75% of the total number of samples studied.     

Determination of imidacloprid in paddy water and soil by liquid chromatography electrospray ionization-tandem mass spectrometry

A method for the determination of imidacloprid in paddy water and soil was developed using liquid chromatography electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS). Separation of imidacloprid was carried out on a Shimadzu C18 column (150 mm × 4.6 mm, 4.6 μm) with an acetonitrile-water (50: 50, v/v) mobile phase containing 0.1% of acetic acid. The flow rate was 0.3 mL/min in isocratic mode. The product ion at 209 m/z was selected for quantification in multiple-reaction monitoring scan mode. Imidacloprid residues in soil were extracted by a solid-liquid extraction method with acetonitrile. Water samples were filtered and directly injected for analysis without extraction. Detection limits of 0.5 μg/kg and 0.3 μg/L were achieved for soil and water samples, respectively. The method had recoveries of 90 ± 2% (n = 4) for soil samples and 100 ± 2% (n = 4) for water samples. A linear relationship was observed throughout the investigated range of concentrations (1–200 μg/L), with the correlation coefficients ranging from 0.999 to 1.000.     

Spectrophotometric Determination of Some Phenolic Antibiotics in Dosage Forms

 A simple and sensitive spectrophotometric method is described for the determination of some phenolic antibiotics namely: cefadroxil, amoxicillin and vancomycin. The method is based on the measurement of the orange yellow species produced when the drugs are coupled with diazotized benzocaine in triethylamine medium. The method is applicable over the range of 0.8–12 μg/ml for cefadroxil, 2–16 μg/ml for amoxicillin and 2–18 μg/ml for vancomycin. The formed compounds absorb at 455 nm for both cefadroxil and amoxicillin and at 442 nm for vancomycin. The proposed method has detection limits of 0.018 μg for cefadroxil, 0.0034 μg for amoxicillin and 0.0156 μg for vancomycin. The stoichiometric ratio for the studied compounds was found to be 1:1 and a proposal of the reaction pathway was made. The proposed method was applied for the analysis of the cited drugs in their pharmaceutical preparations. The results are in good agreement with those obtained by the official methods. Received February 7, 2000. Revision June 14, 2000.     

Determination of triallate and its metabolite 2,3,3-trichloro-prop-2-en-sulfonic acid in soil and water samples

A method based on solid phase extraction was developed for the determination of the herbicide triallate and its metabolite 2,3,3-trichloro-prop-2-en-sulfonic acid (TCPSA). Soil samples were extracted with methanol and diluted with water to yield a methanol/water ratio of 1 : 4. Triallate was adsorbed on C₁₈ cartridges while TCPSA was enriched on quaternary amine anion exchange resins. Cartridges were eluted with methanol/ethyl acetate and methanol/sulfuric acid mixture, respectively. TCPSA methyl ester was formed using trimethyl orthoformate and subsequently analyzed by GC/ECD. Determination limits of both target compounds were 5 μg/kg soil with recoveries of 100 ± 12% for triallate and 57 ± 5% for TCPSA. In water analysis, determination limits were 0.05 μg/L with recoveries of 84 ± 14% for triallate and 100 ± 22% for TCPSA. In laboratory batch experiments, concentration of triallate decreased from 2690 to 1550 μg/kg soil within 59 days. 14 days after triallate application, TCPSA was determined to be 14 μg/kg which increased to 98 μg/kg soil at the end of the incubation period. Soil/water distribution coefficients in loamy sand soil were 102 for triallate and 0.02 for TCPSA which indicated a higher leaching tendency of the polar metabolite. Received: 2 July 1997 / Revised: 15 September 1997 / Accepted: 25 September 1997     

Determination of imazethapyr and imazapyr residues in soil by coupled-column liquid chromatography

Summary A column-switching method using two separation columns combined with UV detection at 260 or 236 nm has been used to determine the imidazolinone herbicides imazethapyr and imazapyr in soils. The residues were extracted from the soil with 0.1 M aqueous sodium carbonate solution and, after adjusting the pH to 2.0, the solution was partitioned with dichloromethane. Limits of determination for imazethapyr and imazapyr were 3 μg/kg. Recoveries were from 55 to 75% for both imidazolinone herbicides in the range 3–100 μg/kg in soil.     

Flow injection analysis with in-line solid phase extraction for the spectrophotometric determination of sulfonated and unsulfonated Quinoline Yellow in Cologne

An integrated solid-phase spectrophotometry/ FIA  method is  proposed for the determination of the synthetic colorant matter Quinoline Yellow (QYWS) in the presence of its unsulfonated derivative QYSS. The procedure is based on the retention and preconcentration of the low level QYSS on a C-18 silica gel minicolumn, followed by sequential measurement of its absorbance at λ = 410 nm after its elution with methanol. The applicable concentration range, the detection limit and the relative standard deviation were the following: for QYWS, from 0.10 to 30.0 mg L^–1; 0.013 mg L^–1; and 0.6%; and for QYSS, between 10 and 1,000 μg L^–1; 2 μg L^–1; and 1.3%, respectively. The method was applied to the determination of small amounts of QYSS present in QYWS in Colognes. Percentages of recovery between 98% and 99% were obtained in all instances. The method was also satisfactorily applied to the determination of these compounds in samples of commercial Colognes comparing the results for QYWS with those offered by an HPLC reference method and also validating the results chemometrically. Received: 21 January 2000 / Revised: 17 March 2000 / Accepted: 22 March 2000     

Immuno-affinity columns versus conventional clean-up: a method-comparison study for the determination of zearalenone in corn

The efficiency of a modern analytical method employing immuno-affinity columns (IACs) is compared to a well established traditional technique with respect to the determination of zearalenone (ZON) in corn in the μg/kg range. Despite of a constant error of about 4 μg/kg in the examined working range of 10–200 μg/kg, analytical data obtained from the analysis of spiked and naturally contaminated samples showed good correspondence for the compared methods. The performance characteristics of immuno-affinity-chromatography as a new clean-up technique for the determination of ZON in corn is reported for the first time and compared to a conventional clean-up procedure Received: 25 March 1997 / Revised: 5 May 1997 / Accepted: 12 May 1997     

A simple solid phase spectrofluorimetric method combined with flow analysis for the rapid determination of salicylamide and salicylic acid in pharmaceutical samples

A new, sensitive and very simple spectrofluorimetric biparameter sensor is described for the determination of salicylamide and/or salicylic acid in pharmaceutical preparations. The method integrates the transitory retention and fluorescence detection of both compounds on Sephadex QAE A-25 resin packed into a conventional flow-through cell. A monochannel manifold with two alternative carriers is used. At pH 2.0 (first carrier) salicylic acid is selectively retained on the solid support and after developing the analytical signal it is desorbed. At pH 11.0 (second carrier) both salicylic acid and salicylamide are simultaneously and transitorily retained on the solid, the analytical signal now corresponding to both analytes. The monochromators were tuned at 260 (excitation) and 415 (emission) nm, respectively. The calibration graph for salicylamide is linear over the range 0.01 to 0.32 μg mL^–1 and for salicylic acid from 0.04 to 1.0 μg mL^–1 in the presence of each other. The relative standard deviation and the sampling frequency for the determination of salicylamide (0.20 μg mL^–1) and salicylic acid (0.50 μg mL^–1) were 1.1% and 35 h^–1, and 0.9% and 45 h^–1, respectively. Good results on application to individual determination or mixture resolution in pharmaceutical samples testify to the usefulness of the proposed sensor. Received: 20 April 1999 / Revised: 7 June 1999 / Accepted: 12 June 1999     

Stabilization of antibodies by haptens

A new, sensitive and very simple spectrofluorimetric biparameter sensor is described for the determination of salicylamide and/or salicylic acid in pharmaceutical preparations. The method integrates the transitory retention and fluorescence detection of both compounds on Sephadex QAE A-25 resin packed into a conventional flow-through cell. A monochannel manifold with two alternative carriers is used. At pH 2.0 (first carrier) salicylic acid is selectively retained on the solid support and after developing the analytical signal it is desorbed. At pH 11.0 (second carrier) both salicylic acid and salicylamide are simultaneously and transitorily retained on the solid, the analytical signal now corresponding to both analytes. The monochromators were tuned at 260 (excitation) and 415 (emission) nm, respectively. The calibration graph for salicylamide is linear over the range 0.01 to 0.32 μg mL^–1 and for salicylic acid from 0.04 to 1.0 μg mL^–1 in the presence of each other. The relative standard deviation and the sampling frequency for the determination of salicylamide (0.20 μg mL^–1) and salicylic acid (0.50 μg mL^–1) were 1.1% and 35 h^–1, and 0.9% and 45 h^–1, respectively. Good results on application to individual determination or mixture resolution in pharmaceutical samples testify to the usefulness of the proposed sensor. Received: 20 April 1999 / Revised: 7 June 1999 / Accepted: 12 June 1999     

Determination of trace impurities in high purity copper using sector-field ICP-MS: continuous nebulization, flow injection analysis and laser ablation

High resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) was applied for multielement-determination in high-purity copper (approx. 99.99%). The samples were introduced into the instrument by three different introduction systems, which were studied with respect to high accuracy, low detection limits and fast analysis: continuous nebulization (CN), flow injection analysis (FIA) and laser ablation (LA). The trueness of the applied method was checked by the analysis of high-purity copper reference material (BCR Cu074). All values obtained for this CRM using CN were in the range of the stated uncertainty for the 9 elements determined: Ag, As, Bi, Cr, Fe, Ni, Pb, Sb, and Sn with contents in the range of 0.5–13 μg/g. Another approach for checking the trueness of the method was to compare the results obtained by this method characterizing the purity of a 4N (99.99% copper content) copper material with those obtained by application of electrothermal atomic absorption spectrometry (ET-AAS) and inductively coupled plasma optical emission spectrometry (ICP-OES). For further characterizing, the concentrations of 49 elements were found in this material below detection limits of HR-ICP-MS in the range of low μg/kg and sub μg/kg. The combination of HR-ICP-MS and a flow injection analysis system (FIAS) improved the robustness of the system in regard to high matrix concentrations. Therefore, matrix concentrations up to 4 g/L could be used for liquid analysis and detection limits were lowered by a factor of 2–5. A calibration method for bulk analysis with laser ablation was developed with doped copper powder as pressed pellets for calibration standards. This method proved to be an excellent fast semi-quantitative method, which was less time consuming in comparison with the analysis of liquids. After application of correction factors the deviation between the results obtained by laser ablation and by analysis of liquids was ≈ 15% for most elements. The method offered the possibility to check for potential losses of analytes occurring during the wet chemical operations. Received: 23 November 1998 / Revised: 25 February 1999 / Accepted: 2 March 1999     

Determination of trace impurities in high purity copper using sector-field ICP-MS: continuous nebulization, flow injection analysis and laser ablation

High resolution inductively coupled plasma mass spectrometry (HR-ICP-MS) was applied for multielement-determination in high-purity copper (approx. 99.99%). The samples were introduced into the instrument by three different introduction systems, which were studied with respect to high accuracy, low detection limits and fast analysis: continuous nebulization (CN), flow injection analysis (FIA) and laser ablation (LA). The trueness of the applied method was checked by the analysis of high-purity copper reference material (BCR Cu074). All values obtained for this CRM using CN were in the range of the stated uncertainty for the 9 elements determined: Ag, As, Bi, Cr, Fe, Ni, Pb, Sb, and Sn with contents in the range of 0.5–13 μg/g. Another approach for checking the trueness of the method was to compare the results obtained by this method characterizing the purity of a 4N (99.99% copper content) copper material with those obtained by application of electrothermal atomic absorption spectrometry (ET-AAS) and inductively coupled plasma optical emission spectrometry (ICP-OES). For further characterizing, the concentrations of 49 elements were found in this material below detection limits of HR-ICP-MS in the range of low μg/kg and sub μg/kg. The combination of HR-ICP-MS and a flow injection analysis system (FIAS) improved the robustness of the system in regard to high matrix concentrations. Therefore, matrix concentrations up to 4 g/L could be used for liquid analysis and detection limits were lowered by a factor of 2–5. A calibration method for bulk analysis with laser ablation was developed with doped copper powder as pressed pellets for calibration standards. This method proved to be an excellent fast semi-quantitative method, which was less time consuming in comparison with the analysis of liquids. After application of correction factors the deviation between the results obtained by laser ablation and by analysis of liquids was ≈ 15% for most elements. The method offered the possibility to check for potential losses of analytes occurring during the wet chemical operations. Received: 23 November 1998 / Revised: 25 February 1999 / Accepted: 2 March 1999     

Flow injection spectrophotometric determination of ultra trace amounts of oxalic acid

A new simple, sensitive and rapid catalytic-spectrophotometric method for the determination of oxalic acid has been described based on its catalytic effect on the redox reaction between dichromate and Brilliant cresyl blue in acidic media by means of a flow injection analysis method. The color change of Brilliant cresyl blue due to its oxidation was monitored spectrophotometrically at 625 nm. The calibration graph was linear in the range of 0.020–4.70 μg/mL oxalic acid with a limit of detection 0.005 μg/mL of oxalic acid. The relative standard deviation for ten replicate measurements of 0.020 μg/mL and 0.900 μg/mL was 2.2% and 1.7%, respectively. No serious interference was identified. Oxalic acid was determined in wastewater and in spinach by the proposed method with satisfactory results. Received: 28 October 1999 / Revised: 13 January 2000 / /Accepted: 20 January 2000     

Determination of ascorbic acid by use of a flow-through solid phase UV spectrophotometric system

A continuous flow-through solid phase spectrophotometric system was developed for the determination of ascorbic acid based on the measurement of its intrinsic absorbance in the UV region when retained on a 1 mm Sephadex QAE A-25 anion exchanger gel layer which is placed into an appropriate quartz flow-through cell, the absorbance exhibited by this solid phase being monitored at 267 nm. A monochannel manifold was used, the sample (300, 600 or 1000 μL) being injected into the carrier solution (acetate buffer). This solution also elutes the analyte after developing the analytical signal, and regenerates the resin layer which, therefore, remains ready for the next sample. The linear dynamic range and other analytical parameters vary according to the sample volume injected. Three calibration lines were established for 300, 600 and 1000 μL sample volume, which ranged from 1.0 to 20.0, 0.5 to 10.0 and 0.2 to 6.0 μg mL^–1, respectively. The detection limits were 0.04 (300 μL), 0.03 (600 μL) and 0.02 μg mL^–1 (1000 μL), the sampling rates 28, 24 and 21 h^–1, and the RSDs (n = 10) 0.87%, 1.08% and 0.90%, respectively. The amount of ascorbic acid in various samples (pharmaceuticals, sweets and urine) were successfully determined with this method. Received: 28 April 1998 / Revised: 3 June 1998 / Accepted: 30 June 1998     

Determination of ascorbic acid by use of a flow-through solid phase UV spectrophotometric system

A continuous flow-through solid phase spectrophotometric system was developed for the determination of ascorbic acid based on the measurement of its intrinsic absorbance in the UV region when retained on a 1 mm Sephadex QAE A-25 anion exchanger gel layer which is placed into an appropriate quartz flow-through cell, the absorbance exhibited by this solid phase being monitored at 267 nm. A monochannel manifold was used, the sample (300, 600 or 1000 μL) being injected into the carrier solution (acetate buffer). This solution also elutes the analyte after developing the analytical signal, and regenerates the resin layer which, therefore, remains ready for the next sample. The linear dynamic range and other analytical parameters vary according to the sample volume injected. Three calibration lines were established for 300, 600 and 1000 μL sample volume, which ranged from 1.0 to 20.0, 0.5 to 10.0 and 0.2 to 6.0 μg mL^–1, respectively. The detection limits were 0.04 (300 μL), 0.03 (600 μL) and 0.02 μg mL^–1 (1000 μL), the sampling rates 28, 24 and 21 h^–1, and the RSDs (n = 10) 0.87%, 1.08% and 0.90%, respectively. The amount of ascorbic acid in various samples (pharmaceuticals, sweets and urine) were successfully determined with this method. Received: 28 April 1998 / Revised: 3 June 1998 / Accepted: 30 June 1998     

Mass spectrometric identification of polychlorinated dibenzothiophenes (PCDBTs) in surface sediments of the River Elbe

HRGC/MS was applied to six sediment samples from River Elbe for the determination of polychlorinated dibenzothiophenes (PCDBTs). Among the studied tri-, tetra- and octa-chlorinated isomers, trichlorinated species were found to be the dominating ones. The estimated concentration levels of the compounds were in the range of approximately 0.02–2 μg/kg dry weight for trichlorinated and 0.1–0.3 μg/kg for octachlorinated species. Tetrachlorinated dibenzothiophenes could not be detected. Received: 7 October 1997 / Revised: 4 February 1998 / Accepted: 9 February 1998     

Separation and preconcentration of Se(IV)/Se(VI) speciation on algae and determination by graphite furnace atomic absorption spectrometry in sediment and water

A novel method for the separation and preconcentration of Se(IV)/ Se(VI) with algae and determination by graphite furnace atomic absorption spectrometry (GFAAS) has been developed. The Se(VI) is extracted with algae from the solution containing Se(IV)/Se(VI) at pH 5.0, and the remaining Se(IV) is then preconcentrated pH 1.0. The detection limits (3σ, n = 11) of 0.16 μg L^–1 for Se(IV) and 0.14 μg L^–1 for Se(VI) are obtained using 40 mL of solution. At the 2.0 μg L^–1 level the relative standard deviation is 2.6% for Se(IV) and 2.3% for Se(VI). The method has been applied to the determination of Se(IV)/Se(VI) in sediment and water samples. Analytical recoveries of Se(IV) and Se(VI) added to samples are ?97 ± 5% and 102 ± 6% (95% confidence), respectively. Received: 10 February 1999 / Revised: 21 June 1999 / /Accepted: 22 June 1999     

Arsenic metabolism in seaweed-eating sheep from Northern Scotland

Cation exchange and anion exchange liquid chromatography were coupled to an ICP-MS and optimised for the separation of 13 different arsenic species in body fluids (arsenite, arsenate, dimethylarsinic acid (DMAA), monomethylarsonic acid (MMAA), trimethylarsine oxide (TMAO), tetramethylarsonium ion (TMA), arsenobetaine (AsB), arsenocholine (AsC), dimethylarsinoyl ethanol (DMAE) and four common dimethylarsinoylribosides (arsenosugars). The arsenic species were determined in seaweed extracts and in the urine and blood serum of seaweed-eating sheep from Northern Scotland. The sheep eat 2–4 kg of seaweed daily which is washed ashore on the most northern Island of Orkney. The urine, blood and wool of 20 North Ronaldsay sheep and kidney, liver and muscle from 11 sheep were sampled and analysed for their arsenic species. In addition five Dorset Finn sheep, which lived entirely on grass, were used as a control group. The sheep have a body burden of approximately 45–90 mg arsenic daily. Since the metabolism of arsenic species varies with the arsenite and arsenate being the most toxic, and organoarsenic compounds such as arsenobetaine the least toxic compounds, the determination of the arsenic species in the diet and their body fluids are important. The major arsenic species in their diet are arsenoribosides. The major metabolite excreted into urine and blood is DMAA (95 ± 4.1%) with minor amounts of MMAA, riboside X, TMA and an unidentified species. The occurrence of MMAA is assumed to be a precursor of the exposure to inorganic arsenic, since demethylation of dimethylated or trimethylated organoarsenic compounds is not known (max. MMAA concentration 259 μg/L). The concentrations in the urine (3179 ± 2667 μg/L) and blood (44 ± 19 μg/kg) are at least two orders of magnitude higher than the level of arsenic in the urine of the control sheep or literature levels of blood for the unexposed sheep. The tissue samples (liver: 292 ± 99 μg/kg, kidney: 565 ± 193 μg/kg, muscle: 680 ± 224 μg/kg) and wool samples (10 470 ± 5690 μg/kg) show elevated levels which are also 100 times higher than the levels for the unexposed sheep. Received: 29 February 2000 / Revised: 26 April 2000 / Accepted: 1 May 2000     

Certified reference material for quantification of polycyclic aromatic hydrocarbons in sediment from the National Metrology Institute of Japan

The National Metrology Institute of Japan has issued a certified reference material (CRM) of freshwater lake sediment for polycyclic aromatic hydrocarbon (PAHs) analyses. The certification used three extraction techniques: pressurized liquid extraction (PLE) with toluene, PLE with dichloromethane/ethyl acetate (1:1 by volume), and alkaline extraction (1 M KOH in methanol) in combination with microwave-assisted extraction. Both gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/dopant-assisted atmospheric pressure photoionization/MS (LC/DA-APPI/MS) analyses were used. Certified values are provided for 18 PAHs at 1–25 μg kg⁻¹ except for perylene (2.08 × 10³ μg kg⁻¹), and information values are provided for two. Since the values of PAHs in the CRM are much lower than those in other CRMs and are comparable to those found at sites with little human influence, the CRM is suitable for PAH monitoring in sediment and soil samples.     

Spectrophotometric Determination of Trace Amounts of Vanadium Based on its Catalytic Effect on the Reaction of Diphenylamine and Hydrogen Peroxide

 In this work a kinetic spectrophotometric method for the determination of trace amounts of vanadium is presented. The method is based on the catalytic effect of the vanadium(V) on the reaction between diphenylamine (DPhA) and hydrogen peroxide in a concentrated solution of formic acid. The formation of the deep-blue oxidation product is followed by a filter spectrophotometer, equipped with an optical fiber assembly, on line with a PC provided with the suitable software. The measurements were taken at 583 nm, with an immersed type cell of 1 cm light path length. The optimization of the operating conditions regarding concentrations of the reagents, temperature and interferences are also investigated. The working curve is linear over the concentration range 0.40–4.0 μg/ml vanadium(V). The relative standard deviation for a standard solution of 0.6 μg/ml of vanadium is 0.5% (n = 5). The proposed method proved highly sensitive, selective and relatively rapid for the assay of vanadium, at low level of 0.40 μg/ml without any pre-concentration step. The method was applied to alloys and cosmetics samples. The results were compared to those received with a reference method. Good agreement was attained, with a mean error of 0.5%. Received February 25, 2000. Revision May 15, 2000.     

Bromide/bromate speciation by NTI-IDMS and ICP-MS coupled with ion exchange chromatography

 Two different mass spectrometric methods, negative thermal ionization isotope dilution mass spectrometry (NTI-IDMS) and inductively coupled plasma mass spectrometry (ICP-MS), off-line and on-line coupled with anion exchange chromatography, have been developed for simultaneous bromide and bromate determinations in water samples. The detection limits of these methods are in the range of 0.03–0.09 μg/L using a 50 mL sample.The results are independent of the content of other anions, which could be demonstrated by the analyses of six mineral waters containing chloride and sulfate of up to 160 mg/L and 1500 mg/L, respectively. Bromide has been analyzed by the NTI-IDMS method in the range of 10–500 μg/L and bromate in the range of 1–50 μg/L with relative standard deviations of 0.3–1.2% and 0.4–6%. Quantification for the ICP-MS method was carried out by the standard addition technique, which resulted in relative standard deviations of 5.5% for bromide at the 500 μg/L level and of 13% for bromate at the level of about 3 μg/L. These results are compared with those described in the literature for ion chromatographic (IC) and other methods and those obtained in this work by IC using UV detection, which allows high concentrations of chloride in the bromate fraction. The detection limits of this IC method are 6 μg/L for bromide and 30 μg/L for bromate. NTI-IDMS and ICP-MS therefore fit the recommendations of the European Union (detection limit<2.5 μg/L; precision and accuracy better than 25% at the 10 μg/L level) for methods analyzing the carcinogenic bromate much better than IC and other methods applied up to now. As a definitive but time consuming method, NTI-IDMS is preferably applicable as a calibration technique, whereas ICP-MS, with relatively short analysis times, due to on-line coupling with chromatography, can be used as a sensitive and powerful routine method for trace bromide and bromate species in water samples. Received: 5 July 1996/Accepted: 7 August 1996