Comparative study of activation analyses for the determination of trace halogens in geological and cosmochemical samples.

Halogens (fluorine, chlorine, bromine and iodine) were determined by activation analyses (neutron activation analysis (NAA), photon activation analysis (PAA) and prompt gamma-ray analysis (PGA)) for geological and cosmochemical solid samples. We studied how each analytical method was for the determination of trace amounts of halogens in rock samples. Radiochemical NAA (RNAA) showed the highest analytical reliability for three halogens (chlorine, bromine and iodine), whereas a set of four halogens (fluorine, chlorine, bromine and iodine) could be determined in principle by radiochemical PAA (RPAA) from a single specimen. Although it is a non-destructive method, PGA showed an analytical sensitivity for chlorine comparable to those of RNAA and RPAA.     

Determination of chlorine, bromine and iodine in rock samples by radiochemical neutron activation analysis

Chlorine, bromine and iodine (hereafter, halogens) were detemined for rock samples by radiochemical neutron activation analysis. The powdered samples and reference standards prepared from chemical reagents were simultaneously irradiated for 10 to 30 minutes with or without a cadmium filter in a TRIGA-II reactor at the Institute for Atomic Energy, Rikkyo University. The samples were subjected to radiochemical procedures of halogens immediately after the irradiation. Iodine was firstly precipitated as PdI₂, and chlorine and bromine were successively precipitated as Ag-halides at the same time. In this study, geological standard rocks, sedimentary rocks and meteorites were analyzed for trace halogens. In some Antarctic meteorites, iodine contents were observed to be anomalously high. Chlorine contents also are somewhat high. The overabundance of iodine and chlorine must be caused by terrestrial contamination on the Antarctica.     

Speciation of halogenides and oxyhalogens by ion chromatography-inductively coupled plasma mass spectrometry

A speciation method utilizing ion chromatography coupled with inductively coupled plasma mass spectrometry is described for simultaneous analysis of eight halogenides and oxyhalogens: chloride, chlorite, chlorate, perchlorate, bromide, bromate, iodide and iodate. The method was applied for the analysis of drinking water samples collected from water treatment plants in areas in Finland, which are known to have high bromine concentrations in ground water. Water samples collected before and after disinfection were analyzed to get information about potential species conversion as a result of purification. Chloride and chlorate were the chlorine species found in these water samples, and iodine existed as both iodate and iodide. In the case of bromine, species conversion had taken place, since total bromine concentrations were increased during disinfection but bromide concentrations were decreased. No bromate was observed in the samples. The detection limits for all the chlorine species studied were 500 μg/l, for bromine species studied 10 μg/l, for iodide 0.1 μg/l and for iodate 0.2 μg/l.     

Application of80m Br to the semi-automated analysis of bromine in biological fluids

A method is presented for the determination of bromine in biological fluids that demonstrates the possibility of adapting neutron activation analysis to large-scale, routine programs. By means of a simple and inexpensive semi-automated system radioactive bromine is separated from one hundred samples per day. A new procedure for determining bromine through measurement of the 36-keV γ-ray of^80m Br has been developed and incorporated into this method. The advantages achieved with this multipurpose separation system and low-energy γ-spectrometry are demonstrated through analyses of urine, serum, plasma and saliva.     

Determination of chlorine and bromine in rocks by alkaline fusion with ion chromatography detection

This study describes the use of alkaline fusion by sodium peroxide to dissolve chlorine and bromine in rocks to produce a solution which, with appropriate pre-treatment, is suitable for analysis by ion chromatography. Results are given for a selection of sedimentary and igneous rocks. The accuracy of the fusion method is evaluated by analysis of Geological Survey of Japan reference materials. Additionally, a spike recovery test is performed to show that the fusion process is quantitative for chlorine and bromine. The results for chlorine are in the range 58–3860 mg kg⁻¹ and show good agreement both with results obtained by pyrohydrolysis with flow injection colorimetric detection and results obtained by aqueous leaching of the samples with ion chromatography detection. Results for bromine are in the range <3–4.5 mg kg⁻¹. Because of the relatively few data obtained in this study and the relative paucity of published data for reference materials, an assessment of the accuracy of the fusion method for bromine is more difficult. The limits of detection for this method are 36 and 3 mg kg⁻¹ for chlorine and bromine, respectively.     

Accurate measurement of bromine contents in plastic samples by instrumental neutron activation analysis

Accurate measurements of bromine contents in plastic samples were made by the direct comparator instrumental neutron activation analysis (INAA). Individual factors affecting the measurements were comprehensively evaluated and compensated, including the volatility loss of bromine from standard comparators, the background bromine level in the filter papers used for preparation of the standard comparators, nuclear interference, γ-ray spectral interference and the variance among replicates of the samples. Uncertainty contributions from those factors were thoroughly evaluated and included in the uncertainty budgeting of the INAA measurement. ⁸¹Br was chosen as the target isotope, and the INAA measurements for bromine were experimentally confirmed to exhibit good linearity within a bromine content range of 10–170 μg. The established method has been applied to the analysis of eight plastic samples: four commercially available certified reference materials (CRMs) of polyethylene and polystyrene and four acrylonitrile butadiene styrene (ABS) samples prepared as the candidate reference materials (KRISS CRM 113-01-012, -013, -014 and -015). The bromine contents of the samples were calculated at three different γ-ray energies and compared, showing good agreement. The results of the four CRMs also showed good consistency with their certified values within the stated uncertainties. Finally, the bromine contents of the ABS samples were determined with expanded uncertainties (at a 95% level of confidence) between 2.5% and 5% in a bromine content range of 25–900 mg kg⁻¹.     

Differentiation of the halogen content of peat samples using ion chromatography after combustion (TX/TOX-IC)

The proposed method for the differential AOX analysis of water samples was tested for its applicability to differentiate the halogen content of peat samples. For determination of the total and the total organic-bound chlorine, bromine and iodine, peat samples were combusted, and the combustion gases trapped and analyzed by ion chromatography (TX/TOX-IC). The total and the organically bound chlorine, bromine and iodine, respectively, can be determined by two-fold analysis with deviations of around 10%. With respect to chlorine more than a double determination could be required. The limit of quantification is 20 mg kg(-1) for chlorine, 2 mg kg(-1) for bromine and 1 mg kg(-1) for iodine, if 25 mg of peat is combusted. The most crucial step of the analysis is the inorganic halogen removal, which is necessary if the organically bound fraction is determined. However, there are some uncertainties about the complete removal of the inorganic halides from the solid samples. Thus, the values of the organically bound fraction have to be discussed as maximal concentrations. Nevertheless, we suggest that the applied method can be useful as a tool for studying the fate of halogens in soils.     

Direct determination of bromine in plastics by electrothermal vaporization/inductively coupled plasma mass spectrometry using a tungsten boat furnace vaporizer and an exchangeable sample cuvette system

A tungsten boat furnace vaporization inductively coupled plasma mass spectrometry (TBF/ICP‐MS) method has been applied to the direct determination of bromine in plastic samples. In the pretreatment, the plastic sample is spread over a small sample cuvette made of tungsten by treating it with a strongly basic organic solution, e.g., octanol or diisobutyl ketone in the presence of potassium hydroxide. The cuvette is placed on a tungsten boat furnace, with which the electrothermal vaporizer is equipped. At the vaporization step, a widely spread thin layer of the sample facilitates its efficient evaporation and introduction into an ICP mass spectrometer. The most remarkable feature is that all the bromine species in plastic samples are decomposed to form a thermally stable inorganic salt during the pretreatment procedure. Therefore, the bromine content in plastic samples can be measured by a calibration curve method constructed with an aqueous standard solution of potassium bromate(V). The detection limit (3σ) was estimated to be 0.77 pg of bromine, which corresponds to a concentration of 0.31 ng g^?1 of bromine in plastic samples when a sample amount taken of 2.5 mg is studied. The relative standard deviation was calculated to be 2.2%. Analytical results of some plastic samples, which contained both inorganic bromide salts and also organic bromine species, are given. Copyright © 2010 John Wiley & Sons, Ltd.     

Use of neutron activation analysis in determination of total organic chlorine and bromine

Neutron activation analysis is practically the only high-sensitivy element-selective detection method for chlorine, bromine and iodine. This method is just ideal for organic halogen determination after separation of organically bound species from inorganic. In recent years we have analysed organic chlorine and bromine from thousands of different kind of samples with different separation methods. For water samples we have used activated-carbon adsorption and for solid samples mostly propanone or combined alkaline/propanone extraction before activated-carbon adsorption. Inorganic chlorides were removed from the carbon by nitrate wash. The detection limits for total organic chlorine and bromine are 5 and 0.5 g/l for water (sample size 100 ml) and 0.3 and 0.1 g/g dry weight (sample size 1 g) for sediment.     

Preconcentration of inorganic mercury and organic mercury with solvent extraction for neutron activation analysis

A preconcentration method combined with neutron activation technique for the analysis of organic and inorganic mercury in waste water samples at ppb levels is presented. The inorganic mercury is extracted in CCl₄ solution with lead diethyldithiocarbamate reagent and the organic mercury is extracted in C₆H₆ solution. Interfering activities of sodium and bromine are removed from the irradiated samples by this procedure. Two different solvent extraction procedures are also described in detail.     

On-line speciation of bromine and bromide using sequential injection analysis with spectrophotometric detection

An on-line procedure for the simultaneous determination of bromine and total bromine (bromine+bromide oxidised to bromine) is proposed, which lead to the determination of bromide by subtraction. Phenol red was used as chromogenic reagent for bromine and total bromine after bromide was oxidised to bromine by Chloramine T. The linear range found is 1-10 mg L(-1) with a detection limit of 0.6 mg L(-1) for bromine, and a linear range of 0.8-15 mg L(-1) with a detection limit of 0.4 mg L(-1) for total bromine. The calculated RSD for bromine is less than 0.8% and for total bromine less than 0.7%. The system is fully computerised and able to run 30 samples per hour with an automated rinsing step that eliminates sample carry-over. The results for both bromine and bromide from the proposed sequential injection analysis (SIA) system compare favourably with standard manual methods and statistical evaluation proves no significant difference between the results of the proposed SIA system and the standard method at the 95% confidence level. The presence of other halides was found not to interfere.     

Determination of arsenic and bromine in hot spring waters by neutron activation analysis

Concentrations of arsenic and bromine dissolved in hot spring waters have been determined by neutron activation analysis using 0.5 cm³ of sample waters without any chemical pretreatment. The samples prepared for neutron irradiation were simply pieces of filter papers which were infiltrated with samples. With the results of satisfactorily high accuracy and precision, this analytical method was found to be very convenient for the determinations of arsenic and bromine dissolved in water at ppm to sub-ppm levels.This revised version was published online in November 2005 with corrections to the Cover Date.     

Determination of the total amount of organically bound chlorine,bromine and iodine in environmental samples by instrumental neutron activation analysis

The determination of chlorine, bromine and iodine present as non-polar, hydrophobic hydrocarbons in environmental samples is reported. The organohalogen compounds are separated from water into an organic phase by on-site liquid—liquid extraction, and from biological material by procedures based on lipid phase extraction and codistillation. After removal of inorganic halides by washing with water and concentration of the sample by evaporation of the solvent, the resulting extracts are analyzed for their chlorine, bromine and iodine contents by instrumental neutron activation analysis. Strict attention is paid to the possibility of contamination in every step of the procedure. Background values in routine analysis are approximately 100–200 ng of chlorine, <5 ng of bromine and <3 ng of iodine.     

Relationship among iodine, bromine and chlorine concentrations in cow's milk in Japan

In order to know the relationship among some elements in biological materials, iodine, bromine and chlorine concentrations in cow's milk samples in Japan were determined by the thermal neutron activation analysis using a low power research reactor and a Van de Graaff accelerator. The iodine contents in cow's milk samples ranged from 0.041 to 0.316 ppm with an average of 0.096 ppm. The bromine and chlorine in these samples ranged from 2.3 to 11.1 ppm and from 475 to 1650 ppm, respectively. The average concentration of the bromine was calculated to be 5.6 ppm and that of the chlorine was 853 ppm. The relationship among iodine, bromine and chlorine concentrations in cow's milk samples in Japan was studied with a regression analysis. It was suggested that the correlation has a power function as follows; Y = K(Z)-A where, Y is elemental concentration in ppm, Z is atomic weight [corrected] of element, A (= 7.4) is exponent and K (= 14.7) is a constant.     

Determination of inorganic impurities in PVC latex by activation analysis

Experimental work was carried out in order to determine inorganic impurities in PVC latex by activation analysis. Arsenic and bromine were detected and quantitatively determined by means of two alternative methods: (a) comparison of the samples and As₂O₃ and KBr standard simultaneously irradiated with slow neutrons; (b) the same as (a), but considering only bromine and using standards made by adding and homogenizing known amounts of KBr in the PVC latex. All measurements were based on γ-spectrometry. The mean values given by method (a) are: arsenic (2.5±0.4)·10⁻⁴%, bromine (1.9±0.1)·10⁻³%. In method (b) the bromine found was (2.47±0.03)·10⁻³%.     

The determination of bromine in biological material by thermal neutron activation analysis

The determination of bromine in biological material by thermal neutron activation analysis using instrumental [Ge(Li)] and radiochemical separation techniques is described. The radiochemical method is ten times more sensitive (0.4 ng) than the instrumental technique but both may be used for analysis of the majority of human tissue samples. Both techniques are rapid, simple, accurate and may be used for batch analysis.     

Determination of iodine and bromine compounds in foodstuffs by CE-inductively coupled plasma MS

A CE-inductively coupled plasma mass spectrometric (CE-ICP-MS) method for iodine and bromine speciation analysis is described. Samples containing ionic iodine (I(-) and IO(3)(-)) and bromine (Br(-) and BrO(3)(-)) species are subjected to electrophoretic separation before injection into the microconcentric nebulizer (CEI-100). The separation has been achieved in a 50 cm length x 75 microm id fused-silica capillary. The electrophoretic buffer used is 10 mmol/L Tris (pH 8.0), while the applied voltage is set at -8 kV. Detection limits are 1 and 20-50 ng/mL for various I and Br compounds, respectively, based on peak height. The RSD of the peak areas for seven injections of 0.1 microg/mL I(-), IO(3)(-) and 1 microg/mL Br(-), BrO(3)(-) mixture is in the range of 3-5%. This method has been applied to determine various iodine and bromine species in NIST SRM 1573a Tomato Leaves reference material and a salt and seaweed samples obtained locally. A microwave-assisted extraction method is used for the extraction of these compounds. Over 87% of the total iodine and 83% of the total bromine are extracted using a 10% m/v tetramethylammonium hydroxide (TMAH) solution in a focused microwave field within a period of 10 min. The spike recoveries are in the range of 94-105% for all the determinations. The major species of iodine and bromine in tomato leaves, salt, and seaweed are Br(-), IO(3)(-), I(-), and Br(-), respectively.     

离子色谱测定农用硫酸铵中4种杂质阴离子

建立了离子色谱法同时测定农用硫酸铵中氟、氯、溴、硫氰酸盐的分析方法。样品经水提取,Ba离子柱净化后,离子色谱法测定。4种阴离子浓度在各自线性范围内与相应峰面积呈线性关系,相关系数r＞0.999,加标回收率为80.23%～111.50%,精密度（RSD）为0.62%~9.08%。称样量为0.1g时,氟、氯的方法检出限为10mg/kg;溴、硫氰酸盐方法检出限为20mg/kg。该方法样品前处理简单、快捷,重复性及回收率均能达到检测分析要求,可以应用于农用硫酸铵中杂质阴离子的检测。     

A comparison of different analytical techniques (energy dispersive X-ray fluorescent spectrometry, bomb calorimetry combined with ion chromatography and inductively coupled plasma-optical emission spectrometry) for the determination of the bromine and antimony content of samples

In recent years, there has been intensive research into the use of pyrolysis to process toxic plastics from waste electrical and electronic equipment (WEEE). During pyrolysis, the fate of the bromine and antimony content of the plastics is critical therefore, new and improved analytical techniques for analysing these elements in the pyrolysis products are being sought. In this work, the effectiveness of energy dispersive x-ray fluorescent spectrometry (EDXRFS) for the determination of bromine and antimony content of pyrolysis oils from waste electrical and electronic equipment have been tested. Samples were obtained by the pyrolysis of brominated high-impact polystyrene (Br-HIPS) and brominated acrylonitrile-butadiene-styrene (Br-ABS) at temperatures from 360 to 440 °C. The concentration range of both the bromine and antimony in the samples was very broad (0.05-17.94 wt% and 0.03-8.54 wt% respectively). The results from EDXRFS to those of more traditional and time consuming methods; bomb calorimetry combined with ion chromatography (EPA method 5050) for bromine and acid digestion combined with inductively coupled plasma-optical absorption spectrometry for antimony were compared.Based on our measurements, different statistical parameters were calculated for each analytical technique, which demonstrated that EDXRFS had been successfully applied to the determination of bromine and antimony concentration in the pyrolysis oils of Br-HIPS and Br-ABS. Errors resulting from matrix effects did occur, in particular correlations were found between the nitrogen content of the samples and the difference in bromine and antimony measured by EDXRFS and other methods (ion-chromatography and ICP-OES). However, these differences were found to be statistically insignificant, so we could conclude that EDXRFS is a suitable technique for analysing the bromine and antimony content of pyrolysis oils.