Determination of bromine, chlorine and iodine in environmental aqueous samples by epithermal neutron activation analysis and Compton suppression

Summary Halides, particularly Br^- and Cl^-, have been used as indicators of potential sources of Na⁺ and Cl^- in surface water and groundwater with limited success. Contamination of groundwater and surface water by Na⁺ and Cl^- is a common occurrence in growing urban areas and adversely affects municipal and private water supplies in Illinois and other states, as well as vegetation in environmentally sensitive areas. Neutron activation analysis (NAA) can be effectively used to determine these halogens, but often the elevated concentrations of sodium and chlorine in water samples can give rise to very high detection limits for bromine and iodine due to elevated backgrounds from the activation process. We present a detailed analytical scheme to determine Cl, Br and I in aqueous samples with widely varying Na and Cl concentrations using epithermal NAA in conjunction with Compton suppression.     

Determination of trace elements in food by neutron activation analysis

Neutron activation analysis (NAA) methods have been developed for the determination of major, minor and trace elements in duplicate diets and individual food items. These include a cyclic instrumental NAA (CINAA) method for measuring Se content through its short-lived nuclide^77mSe; epithermal INAA (EINAA) for I and As; conventional INAA for Br, Ca, Cl, Co, Cr, Fe, K, Mg, Mn, Na, Rb, Sb, Sc, Sn and Zn; combination of EINAA and INAA for Al; radiochemical NAA (RNAA) for As, Au, Co, Cu, Fe, Hg, Mo, Sb, Se and Zn; and preconcentration NAA (PNAA) for U and Th. Accuracy of measurements have been evaluated by analyzing a number of biological and diet reference materials. Multielement concentrations of diets and foods have been measured by these methods.     

Analysis of natural milk and milk poweder samples by NAA

As a part of the Iraqi Food Analysis Programme /I.F.A.P./ the concentration of Na, Mg, P, Cl, K, Ca, Zn, Se, Br, Rb and I in natural milk collected from different regions of Iraq, and in milk powder samples have been determined by using the NAA technique. It was found that except for the elements I, Rb and Br the concentration of the elements was approximately identical in both the natural milks and milk powders.     

Neutronenaktivierungsanalytische Untersuchung eines Luna-16-Olivineinkristalls

A lunar olivin monocrystal (Mg, Fe)₂SiO₄ of about 0.011 mg was analyzed by neutron activation analysis (NAA) and by X-ray crystal structure research (XRCSR). Both methods demonstrated the presence of small concentrations of Sc, Cr, Mn, and Co, the quantitative results for these elements are in the range of about 10² to 10³ ppm. Mg was analysed only by XRCSR. Good agreement between both methods was found for the concentrations of Fe and Na, the Fe excess by NAA can be explained with included impurities.      

Determination of 24 elements in four algae reference materials by neutron activation analysis and inductively coupled plasma mass spectrometry

Four algae reference materials, IAEA-391, 392, 393 and IAEA-140, prepared by the International Atomic Energy Agency for intercomparison under different preparation conditions were analyzed for 24 elements. Conventional neutron activation analysis (NAA) was used to determine Al, Ca, Cl, Co, Cr, Cu, Fe, K, Mg, Mn, Mo, Na, Sb, V and Zn and epithermal NAA using BN and Cd as shielding material for I, Br, As, Ni, Mo and Cd. Inductively coupled plasma mass spectrometry (ICP-MS) as a complementary and comparative method was applied to determine Pb, Sn, Ni, Sr, Rb, As, Co, Cr, Cu, Mn, V, Mo and Zn. Two analytical quality control standard reference materials IAEA-V-10 (hay powder) and IAEA-331 (spinach) were analyzed simultaneously with real samples. The results agree quite well with each other and with the certified values.     

Neutron activation analysis of Californian and Japanese rice

The main motivation in studying different types of rice was to determine how processing of rice affects its mineral composition, and to compare how it affects rice dietary intake. Specifically the estimated difference in between the brown and white rice produced in Japan and California are studied. These various rice samples were analyzed using neutron activation analysis technique available at the Utah Nuclear Engineering Program (UNEP). Samples were prepared using novel technique developed at UNEP and submitted for short and long irradiation. The detected elements were As, Br, Cl, Cd, Mn, Na, K. The concentrations of Mn, K and Na are significantly higher in the brown then in the white rice, while As, Br and Cl have more homogeneous presence and therefore smaller difference in concentration. Elemental concentration was compared with The Institute of Medicine (IOM) in the United States values of recommended dietary allowance and Food and Drug Administration (FDA) limits for harmful elements. From these measurements, only the concentration of Mn in rice satisfies daily needs in the range set as defined by IOM. The concentrations of potentially harmful elements are lower than FDA limits.     

Complexation of Eu3+ with cone conformers of three substituted calix[4]arenes in nitrobenzene saturated with water

From extraction experiments and $ \gamma Accurate knowledge of the trace elemental concentrations in wheat and its products is of great importance from a nutritional point of view. In this study, six wheat samples were prepared from the agriculture research center of Arak named Sardari, Amir, MV-17, Batava, Karaj-2 and Alvand; they were analyzed by neutron activation method (NAA). In this method, Isfahan miniature reactor as a neutron source and relative NAA method has been used as the analysis type. In this design in order to record gamma spectrum the MCA system and high purity germanium detector were used. Finally, the concentration of the trace elements such as Br, K and Na value was determined for the Sardari, Amir, Alvand, MV-17, Batava, Karaj-2 wheat samples. The average concentration of trace elements in all wheat samples in the studied area are 2.41(0.8597?6.1175) mg kg^?1 for Br, 13.42(8.7063?24.696) mg kg^?1 for Na and 463.30(434.22?505.45) mg kg^?1 for K, respectively. These were compared with other reports results. This study has been conducted as the first time for this region.     

Evaluation of sample preparation methods for elastomer digestion for further halogens determination

In this work, three sample preparation methods were evaluated for further halogen determination in elastomers containing high concentrations of carbon black. Samples of nitrile-butadiene rubber, styrene-butadiene rubber, and ethylene-propylene-diene monomer elastomers were decomposed using oxygen flask combustion and microwave-induced combustion (MIC) for further Br and Cl determination by ion chromatography (IC), inductively coupled plasma optical emission spectrometry (ICP OES), and inductively coupled plasma mass spectrometry (ICP-MS). Extraction assisted by microwave radiation in closed vessels was also evaluated using water or alkaline solution. Digestion by MIC was carried out using 50 mmol l⁻¹ (NH₄)₂CO₃ as the absorbing solution. The effect of the reflux step was also evaluated. Accuracy was evaluated using certified reference materials with polymeric matrix composition and by comparison of results using neutron activation analysis. Agreement for Br and Cl was better than 95% by MIC using 5 min of reflux, and no statistical difference was found using IC, ICP OES, and ICP-MS for determination of both analytes. For MIC, the relative standard deviation (RSD) was lower than 5%. Using extraction in closed vessels, a high amount of residues was observed, and recoveries were lower than 45% for both analytes. For oxygen flask combustion, the agreement was similar using MIC but RSD was higher (20%). The residual carbon content, an important parameter used to evaluate the digestion efficiency, was always below 1% for MIC. Using MIC, it was possible to digest elastomers with high efficiency, resulting in a single solution suitable for halogen determination by different techniques.     

Analysis of marine biological certified reference material by various non-destructive neutron activation methods

By the use of non-destructive neutron activation analysis (NAA) twenty-four trace (Ag, As, Br, Cd, Ce, Cr, Co, Cu, Eu, Fe, Hf, I, La, Mn, Ni, Rb, Sb, Sc, Se, Sm, Sr, U, V and Zn) and six minor (Ca, Cl, Mg, K, Na and S) elements were determined in a certified marine tissue standard reference material. Four non-destructive methods including thermal, epi-thermal, prompt-gamma ray and delayed neutron counting activation analyses were performed. Results when compared to the certified values showed the reliability of employing these methods in such standards program.     

Instrumental neutron activation analysis of spruce needles and trees

Tree rings and needles of young spruce clones from the immission area of the Al-refinery Ranshofen (Upper Austria), which had ceased production in 1992, were investigated by INAA. Short time irradiation was performed for determining, Al, Mn, Ca and Cl, while the elements Na, K, Rb, Ba, Zn, Fe, Sc, Cr, Co, Br and in some samples also Ca were determined via middle- and long-lived radioisotopes. Irradiation and counting conditions are given. Accuracy and sensitivity are sufficient to describe the trends of the element concentrations in needles and with the exception of Cr, Sc and Br, in tree rings. Ca-concentrations derived from⁴⁹Ca (short-time irradiation) and⁴⁷Ca (long-time irradiation) are compared and show good agreement Additionally Mg was determined in some samples by ICP-AES and if possble, by INAA. The results are compared.     

Analysis of serum and whole blood using NAA for clinical investigation

The concentrations of Cl, K and Na were analyzed in human body fluids (whole blood and serum) using NAA, resulting in the first biochemical baseline values for the Brazilian population. These data permitted us a discussion about the advantages and limitations of using this analytical technique for clinical chemistry.     

RNAA for arsenic,cadmium, copper,and molybdenum in CNS tissues from subjects with age-related neurodegenerative diseases

Reactor thermal neutron irradiation of biological matrices induces high levels of intense gamma-ray or bremsstrahlung radiation from⁸²Br,⁴²K,²⁴Na, and³²P, that interfere with the determination of As, Cd, Cu, and Mo by INAA. Central nervous system (CNS) issue samples from subjects with Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), and controls were analyzed using a simple RNAA procedure involving a rapid two-step solvent extraction procedure to determine these four elements. Significant increases (p0.05) in concentrations of Cd and Mo were observed for brain of AD subjects compared to controls, but significant imbalances were not observed for ALS subjects. Concentration data for these elements in selected international reference standards are also presented.     

Subcellular distribution of Al, Cu, Mg, Mn and other elements in the human liver

The elemental concentrations and chemical species of Al, Br, Cl, Cu, K, Mg, Mn, Na and I in human liver and its subcellular fractions were studied by several biochemical techniques combined with neutron activation analysis. The highest concentrations of Al, Mg, and I were found in the nuclei, whereas those of Br, Cu, Cl, K, Mn and Na in the cytosol. About 20% of Br, half of Al and most of Cu (78.8%), Mg (65.9%) and Mn (80.6%) remained in the cellulose bags after dialysis of liver homogenate, which were suggested to be bound to macromolecules. K (100%) and more than 95% of Cl and Na were found to be in the dialyzates. Similar results were found in the fractions of nuclei, mitochondria, lysosome and microsome, respectively, after the same treatment. Further study was carried out to elucidate the elemental distribution in the cytosol by ethanol precipitation and by ammonium sulfate fractionation. The results suggested that several kinds of Cu-, Mn- and Mg-bound proteins existed in the cytosol of human liver cells. Received: 3 August 1998 / Revised: 22 September 1998 / Accepted: 26 September 1998     

INAA of IAEA-331 (spinach), SRM,for 40 elements

Forty elements in IAEA-331 (Spinach), an intercomparison material, have been determined using NAA. Among them, 30 elements, Ag, Al, Ba, Br, Ca, Ce, Cl, Co, Cr, Cs, Eu, Fe, Hf, K, La, Mg, Mn, Na, Ni, Rb, Re, Sc, Se, Sr, Ta, Tb, Th, V, Zn and Zr were determined by INAA. A series of simple and quantitative radiochemical separation procedures were established for the determination of ten additional elements. Cd, Lu, Mo, Sb, Sm, Yb, U were determined by removing the major interfering nuclide⁸²Br. Cu was determined by 0.048M NaDDTC/CHCl₃ extraction from 1M HCl medium. As and P were determined using an inorganic exchange column of acid aluminium oxide (AAO). Integral counts from 80 keV to 130 keV contributed by Bremsstrahlung from³²P -were used to evaluate the content of phosphorus.     

Determination of Bromide,Chloride, and Fluoride in Cigarette Tobacco by Ion Chromatography after Microwave-Induced Combustion

A microwave-induced combustion (MIC) method was applied for cigarette tobacco digestion and further determination of bromide (Br), chloride (Cl), and fluoride (F) by ion chromatography (IC). Samples (up to 500 mg) were combusted at 20 bar of oxygen. Combustion was complete in less than 30 s, and analytes were absorbed in (NH₄)₂CO₃ solutions. A reflux step, not available in other systems, was applied to improve analyte absorption. Absorbing solution with 50 mmol L^?1(NH₄)₂CO₃ was selected because it showed recovery close to 100% for samples containing spikes of halogens. Accuracy of the proposed procedure was evaluated by analysis of certified reference materials and the agreement was better than 97% for all analytes using 50 mmol L^?1 (NH₄)₂CO₃ as absorbing solution and 5 min of reflux. Temperature during combustion was higher than 1400°C and the residual carbon content was always lower than 1%. With the use of the MIC system, up to eight samples could be processed simultaneously, and a single absorbing solution was suitable for all analytes. Limits of quantification by MIC and further IC determination were 0.50, 0.20, and 0.10 µg g^?1 for Br, Cl, and F, respectively.     

Study of trace impurities in heroin by neutron activation analysis

Sixty-two heroin samples were analyzed for their contents of 15 trace elements (Au, Ba, Br, Ca, Ce, Co, Cr, Fe, La, Na, Sb, Sc, Sm, Th, and Zn) by neutron activation analysis (NAA). Large variations of elemental concentrations between samples were found to possess statistical significance. Of all the elements calcium was the most abundant element, followed by zinc and sodium. The concentrations of Au, Ce, Co, La, Sb, Sc, Sm, and Th in all the samples were below 1 mg·g⁻¹. Classification of these heroin samples was achieved by the application of hierarchical cluster analysis. The results show that NAA can provide useful information on the origin of the illicit drugs. This revised version was published online in July 2006 with corrections to the Cover Date.     

Multivariate data analysis of some Finnish water courses

Summary The following parameters were analyzed 2 to 4 times a year from 37 sampling sites; T, O₂, O₂%, Turbidity, Suspended solids, Conductivity, Alkalinity, pH, Color, COD_Mn, Total nitrogen, Total phosphorus, Cl, Fe, Mn, Total sulphur, K, Na, Ca, Mg, SiO₂, Total organic chlorine and Total organic bromine. Samples were taken from waters loaded by chemical pulp mills, other industries, municipal waste waters and agriculture. Also waters under natural conditions were included. Water samples have been collected and analyzed in co-operation with the National Board of Waters and the Environment. The data set was analyzed by Principal Component Analysis (PCA) to determine correlations between variables, especially between Total organic chlorine and Total organic bromine and others. Typically Total organic chlorine and Total organic bromine correlated with Na, Cl and Total sulphur. It is interesting to note that Total organic chlorine and Total organic bromine did not follow each other in all components. Total organic chlorine was predicted using other variables and Partial Least Squares (PLS) method. Very satisfactory correlation was obtained between analyzed and predicted lgTOCl values. Optimally three different object classes were found from the whole data using fuzzy clustering analysis. One class represents waters in a natural condition, one water loaded mainly by agriculture and one represent the rest of the waters.     

Determination of trace elements in bottled water in Greece by instrumental and radiochemical neutron activation analyses

Summary Four different bottled water brands sold in Greece in the winter of 2001-2002 were analyzed for a wide range of chemical elements, using neutron activation analysis (NAA). The elements Na and Br were determined instrumentally (INAA), whereas the other metals and trace elements radiochemically (RNAA). The results indicated that the mean level of all the elements determined in the samples were well within the European Union (EU) directive on drinking water and accomplish the drinking water standards of the World Health Organisation (WHO) as well as of the Food and Drug Administration (FDA).     

Neutron activation analysis correction for the calculation of bromine concentrations via the79Br(n, γ)80Br reaction

Bromine can be determined by neutron activation analysis (NNA) through either the activation of⁷⁹Br (50.69% naturally abundant) or⁸¹Br (49.31% naturally abundant). When⁷⁹Br is activated, both^80mBr and⁸⁰Br are produced.^80mBr (4.42 h) decays to⁸⁰Br (17.66 m) which then beta decays to either⁸⁰Se or⁸⁰Kr. If one would like to determine bromine concentrations with short lived NAA, special equations must be used to account for the parent daughter relationship between^80mBr after their simultaneous production. The development of the equations needed to calculate bromine concentrations with short-lived NAA is described including variations on irradiation times, decay times, and count times.     

Determination of 18 trace elements in petroleum and its derivatives by neutron activation with a small nuclear reactor

Non-destructive neutron activation has been used to analyze 6 different samples of crude oil and heating oil, from Western Canada and Venezuela. These samples were irradiated with thermal neutrons for 2, 30 and 240 min in the SLOWPOKE reactor and the concentrations of 18 trace and minor elements (Al, As, Br, Cl, Co, Dy, Eu, Fe, I, La, Mn, Mo, Ni, Na, S, Se, Sm and V) ranging from 0.6 ppb to 2.24% have been measured. Eleven elements (As, Br, Co, Cl, Fe, Mo, Mn, Na, Ni, S and V) were determined in the fuel oil (SRM-1634) obtained from the National Bureau of Standards and were found to be in good agreement with the values certified by NBS