A relatively simple assay method for the putative cytosolic ‘receptor’ that binds 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and related compounds is described. The assay is based on specific binding of [125I]dioxin to cytosol ‘receptor’ protein. Saturation is ensured by competition experiments in which unlabeled TCDD and other competitors displace the radiolabeled ligand from specific binding sites. This assay has been applied to estimation of levels of ‘receptor’ in cytosol.View

Expand abstractUptake and Elimination of 14 C-Aldrin and 14 C-Dieldrin by the Ostracod Chlamydotheca Arcuata (Sars)Article

  • Jun 1972

Laboratory-reared, insecticide-free fresh-water ostracods, Chlamydotheca arcuata (Sars), were exposed to various concentrations of C-aldrin and C-dieldrin. Aldrin and dieldrin were accumulated in or by ostracod tissue both with and against concentration gradients from water. The initial rate of aldrin accumulation was approximately twice that of dieldrin, and accumulation of either insecticide was dependent upon the insecticide concentration in water, the duration of exposure, and the activity of the animals. Aldrin was readily metabolized to dieldrin in living ostracods, and small amounts of dieldrin were eliminated. The rate of elimination was in part dependent upon ostracod activity, although some elimination occurred with dead animal tissues. Dieldrin was eliminated more rapidly by dieldrin-exposed ostracods than by aldrin-exposed ostracods.View

Expand abstractHydrocarbons in the Western Mediterranean Sea, 1981Article

  • Feb 1982

Hydrocarbons in the western Mediterranean Sea were analysed for surface microlayer and subsurface waters during April 1981. Three methods were used for determining both concentrations and markers distribution patterns: U.V. spectrofluorimetry, and original HPLC/U.V. spectrophotometry method and capillary gas liquid chromatography. No systematic relationship was found between concentrations determined by U.V. spectrofluorimetry and HPLC/U.V. spectrophotometry. Concentrations variation ranges are: 0.01-0.20 microgram 1(-1) for dissolved aromatic hydrocarbons; 0.02-0.13 microgram 1(-1) for particulate aromatic hydrocarbons; 0.02-20.57 micrograms 1(-1) for dissolved n-alkanes; 0.13-0.83 microgram 1(-1) for particulate n-alkanes. Surficial waters appear as very slightly polluted with an exception the Ligurian Sea for which highest concentrations were encountered. There is a slight enrichment of particulate hydrocarbons in the surface microlayer in the range 1-3. But, dissolved hydrocarbons can be either depleted or enriched up to 270 times in the surface microlayer, indicating the extreme efficiency of sea-air exchange processes. Aromatic fingerprints and n-alkane distribution patterns are discussed both for pollution and fractionation processes indicators at the sea-air interface.View

Expand abstractThe Photodecomposition of 1,l-Dichloro-2,2-bis(5′-chloro-2′-methoxyphenyl)ethylene (MPE), an Analogue of DDEArticle

  • Jun 1972

The solution-phase photodecomposition of l, l-dichloro-2,2-bis(5′-chloro-2′-methoxy-phenyl)ethylene (MPE) has been studied at an excitation wavelength of 313 nm in the presence of O2 as well as in vacuum-degassed solutions. Only two non-volatile compounds are produced: 2,5-dichloro-3-(5′-chloro-2′-methoxyphenyl)benzofuran (BFD) and a minor product which was not identified. The BFD represents approximately 90% of the total non-volatiles. The volatile products were identified as CH3Cl, CH4 and HC1, with CH3C1 being approximately 99.9 % of the total volatiles. Photolyses were carried out in C6H12 and CCI4 solvents, the same products being observed in both solvents. Variation of MPE concentration has little or no effect on the relative quantum yield of decomposition. The photodecomposition of MPE does not follow the same pathway as the photodecomposition of DDE.View

Expand abstractA Method for Determination of Low Levels of Exposure to 2,4-D and 2,4,5-TArticle

  • Sep 1971

A method has been developed for the determination of trace quantities of 2,4-dichloro-phenoxyacetic acid (2,4-D), 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), 2,4-dichlorophenol (2,4-DCP), and 2,4,5-trichlorophenol (2,4,5-TCP) in human and rat urine. The method involves acid hydrolysis of the phenolic conjugates, extraction of the free phenols and acids, ethylation with diazoethane, silica-gel column chromatography clean-up of the derivatized urine extract, and gas chromatographic determination using the electron-capture detector. The average recoveries of 2,4-D, 2,4,5-T, 2,4-DCP, and 2,4,5-TCP from rat urine spiked with known amounts of the herbicides and their phenols were 94%, 98%, 92%, and 90%, respectively. The limits of detection for 2,4-D, 2,4,5-T, DCP, and TCP in rat urine were: 0.05, 0.01, 0.10, and 0.01 ppm, respectively. The method was used to analyze urine of rats given various levels of 2,4-D and 2,4,5-T by gavage. Results showed that levels of exposure of 3.75 mcg/kg for 2,4-D and 5.0 mcg/kg for 2,4,5-T in rats can be detected in urine within 24 hr from exposure. Urine samples from occupationally exposed people were analyzed and found to contain 0.2 to 1.0 ppm 2,4-D and 0.05 to 3.6 ppm 2,4,5-T.View

Expand abstractThe Determination of Formaldehyde in Beer and Soft Drinks by HPLC of the 2,4- Dinitrophenylhydrazone DerivativeArticle

  • Feb 1983

A simple procedure was developed for the determination of formaldehyde in samples of beer and soft drinks. A volume of sample was distilled and the aqueous distillate containing the formaldehyde collected directly in a solution of 2,4-dinitrophenylhydrazine. The resulting hydrazone was extracted and analysed by reversed-phase high-performance liquid chromatography with UV absorbance detection. Levels of formaldehyde found were in the low mg/kg range. Detection limits were less than 0.1 mg/kg of sample. Results were confirmed by mass spectrometry (probe) of the derivatives after fraction collection from the HPLC.View

Expand abstractTrace Analysis of 2,4,5, TP and other Acidic Herbicides in Wheat Using Multicolumn-HPLCArticle

  • Feb 1984

In continuation of our work dealing with multicolumn HPLC (MC-HPLC) techniques and their applicabilities for tracing a few compounds out of complex multicomponent matrices a residue analysis of the herbicides 2,4,5T and MCPA (phenoxyacids) in wheat is described. A simple plant extract with aqueous basic buffer is loaded in quantities of several 100 microliters onto a strong anion exchanger (column 1,C1) performing extraction of the acidic compounds, while the neutral and cationic substances are eluted thus attaining on-column trace enrichment. Via mobile phase selection (pH change) elution from C1 is possible, the fraction (zone-cut) containing the compounds of interest is transferred onto C2 (reversed phase, RP2 and RP18) on which peak compression is performed followed by (step)gradient elution. Detection limits in the lower ppb range are routinely obtained. A MC-HPLC chromatographic setup separation of eleven acidic herbicides in a formulation is also shown.View

Expand abstractEstimation of N -ethyl O -isopropyl Thionocarbamate (Dow: 2-200) in Mine Wastes by GLCArticle

  • Feb 1974

Dow 2200 is a selective ore flotation agent, consisting mainly of Nethyl, 0-isopropyl thionocarbamate (IF’ETC). This paper describes a GLC method for the estimation of IPETC, and compares it with the conventional U.V. spectrophotometric procedure.An aliquot of a cyclohexane extract of IPETC (prepared for spectrophotometric analysis) is chromatographed on a column of SE-30 or OV-17/QF-1 at 125°C and the IPETC peak is estimated in a 3H electron capture detector (ECD). The ECD is superior in sensitivity and linearity of response to the flame photometric detector operated in the S-mode. The ECD-GLC procedure is comparable in sensitivity to the conventional U.V. absorbance method, and offers an independent and complementary procedure useful for confirmation of low levels of IPETC.View

Expand abstractSpecific Activity of 210 Pb in the EnvironmentArticle

  • Feb 1974

A review of data on the specific activity of Pb (pCi Pb/mg stable Pb) in the environment is presented. Experimental results on aerosol, plant, animal and human samples from Finland are reported. Large variations (18-2450 pCi/mg Pb) were observed for aerosol samples taken from various locations and under different meteorological conditions. Results for the biological samples revealed a much narrower range. A considerable decrease of specific activity was observed along the food chain plant—animal—man, thus indicating contamination of the food chain by technological (low-activity) lead. Arctic values of specific activity were observed to be generally higher than “normal” values. Human samples from southern Finland contained about 20pCi Pb/mgPb. Possibilities of utilizing specific activity measurements in lead pollution studies and in elucidating the origin of stable lead in the human diet are discussed.View

Expand abstractDetermination of 23 Polycyclic Aromatic Hydrocarbons in Atmospheric Particulate Matter of the Paris Area and Photolysis by SunlightArticle

  • Feb 1985

Twenty-three polycyclic aromatic hydrocarbons (PAH) were determined in atmospheric particulate matter in 4 places of the Paris area at several times of the year. Fractionation was performed by reversed-phase high-pressure liquid chromatography. Determination was done by recording emission or excitation fluorescence spectra via a stopped-flow technique. Triphenylene was also extemporaneously determined by its phosphorescence spectrum at low temperature. Among the PAH determined dibenz(e,ghi)perylene has not been detected before in atmospheric particulate matter. The 10 more abundant PAH ranged from 0.1 to 40 ng/m3 of filtered air. Concentrations in August are from 14 to 250 times less than in January depending on the PAH. The reasons for this difference of behaviour among the PAH were investigated with regard to their photochemical and non-photochemical reactivity.View

Expand abstractThe photochemistry of carbamates, I. The photodecomposition of Zectran: 4 dimethylamino 3,5 xylyl N methyl carbamateArticle

  • Mar 1973

The photodecomposition of 4-dimethylamino-3,5-xylyl-N-methyl carbamate (Zectran) in aerated and degassed solution has been carried out. Three major photoproducts were detected and characterized to be: 4-dirnethylamino-3,5-dimethyl Rhenol, 4-hydroxy-2,6-dimethyl-N-methyl benzamide and 4-monomethylamino-3,5-xylyl-N-methyl carbamate. The phenol and benzamide products suggest that one of the pathways of photodecomposition of Zectran is via a photo-Fries rearrangement. The ortho-benzamide (5-dimethylamino-4,6-dimethyl-2-hydroxy-N-methyl benzamide) which could also be expected to occur in a photo-Fries reaction, was not observed. The excitation wavelength was > 296.7 nm, i.e. radiation available in the solar spectrum. Thus the products observed in this study may be expected to occur in the environment as a result of the action of sunlight on Zectran.View

Expand abstractDetermination and Persistence of Bay 68138 and Two of its Metabolities in Turf GrassArticle

  • Jun 1972

Residues of Bay 68138 (Nemacur P) [ethyl 4-(methylthio)-m-tolyl isopropylphosphor-amidate] and its sulfoxide and sulfone were determined in turf grass. The extracts were separated by liquid chromatography on silica gel into two fractions which were concentrated and injected into a gas chromatograph equipped with a flame photometric detector sensitive to phosphorus. Recoveries were 95 to 105 % for all three compounds at the 0.10-ppm level; sensitivity to each compound was 0.01 ppm or better. Retention times for the three compounds on six liquid phases, p-values in seven solvent systems, and conditions for separating the compounds by liquid chromatography were determined. Total residues in turf grass treated with a granular formulation at the rate of 15 lb (active ingredient) per acre, declined from 4930 to 102 ppm (dry basis) during a 49-day period of weathering. Bay 68138 was found to oxidize to its sulfoxide and sulfone.View

Expand abstractSpectrophotometric Determination of Copper in Environmental Samples by Solid-liquid Extraction of its 9,10-Phenanthrenequinone Monoximate Complex into Molten NaphthaleneArticle

  • Feb 1986

A fairly selective and sensitive spectrophotometric method has been developed for determination of copper after extraction of its 9, 10-phenanthrenequinone monoximate complex into molten naphthalene in the pH range of 6.1-8.4. At room temperature, the solid naphthalene containing the metal complex is separated by filtration, dissolved in dimethylformamide (DMF) and the absorbance measured at 470 nm against the reagent blank. Beer’s law is obeyed in the concentration range, 0.0-9.6 micrograms of copper in 10ml of DMF. The molar absorptivity and sensitivity are 6.30 X 10(4) 1 mol-1 cm-1 and 0.001 micrograms cm-2, respectively. The interference of various ions has been studied and the method has been applied for the determination of copper in various standard reference materials, beers, wines, human hair and environmental samples.View

Expand abstractBay 93820 Residues: Their Determination and Persistence in Coastal Bermudagrass, Forage Corn, and Corn SilageArticle

  • Sep 1971

Residues of Bay 93820 (isopropyl salicylate O-ester with O-methyl phosphoramidothioate) and its oxygen analog were determined in Coastal bermudagrass (Cynodyn dactylon (L.) Pers.), corn, and corn silage. The insecticide was applied in the field as aqueous sprays of an emulsifiable concentrate at rates of 6, 12, and 24 oz (active ingredient) per acre. Glass jar silage was made from 1-day post-field treatment corn. Residues were analyzed by gas chromatography by using a flame photometric detector sensitive to phosphorus; details of the analytical procedure are presented.Residue levels of Bay 93820 in both corn and grass diminished to less than 1 ppm after 14 days of weathering in the field. Residues of the O-analog were lower than those of Bay 93820; however, they represented a much larger portion of the total residue than with any other O-analog-forming organophosphorus insecticide previously tested at our laboratory. Residues of Bay 93820 were essentially stable and persistent in corn silage, whereas the small amounts of O-analog tended to increase slightly.View

Expand abstractDetermination of Pentachlorophenol in Wood Samples Using Liquid Chromatography With UV Absorbance, Amperometric and Electron-Capture DetectionArticle

  • Feb 1986

The potential of reversed-phase liquid chromatography (RPLC) with UV and amperometric detection (AD), and of normal-phase liquid chromatography (NPLC) with UV and electron-capture detection (ECD) for the determination of pentachlorophenol (PCP) in wood samples has been studied. When PCP concentrations of at least 1-5 ppm have to be determined, RPLC-UV and RPLC-AD on C18-modified silica are useful techniques, provided a two- or three-step sample-preparation step is used. NPLC-UV on bare silica columns does not offer any advantage over RPLC-UV. NPLC-ECD on bare silica and with an acidified toluene-hexane mixture as eluent offers good selectivity and sensitivity, as well as satisfactory linearity and reproducibility for the determination of PCP in wood samples down to low ppb levels. Use of the two-step clean-up procedure is sufficient, and even a single-step procedure has been utilized. In the latter case, analysis times are longer because of the presence of late-eluting ECD-active interferences. The two-step clean-up procedure generally used involves a liquid-liquid extraction with dichloromethane, and solid-liquid sorption using a Sep Pak C18 cartridge. PCP recovery over the 0.2-10 ppm range is 75-100%. Several wood samples containing 1-50 ppm of PCP have successfully been analyzed, and the good potential of NPLC-ECD for trace-level determination of PCP has been demonstrated.View

Expand abstract[A new method for quantitative measurement of the cadmium absorbed by chick embryos].Article

  • Feb 1984

We attempted to determine the quantity of cadmium incorporated in hens eggs after immersion in cadmium solutions, and the cadmium concentration measured in embryos. We discussed equipment allowing simultaneous treatment of up to 42 samples, and called it ” digestor “. It consisted of two gas-heated sand baths, two stands for cooling down solutions and an evacuation system for toxic vapours. Our method was based on wet mineralisation. It consisted of desintegrating experimental chick embryos in a HNO3/H2O2 mixed solution. After heating and evaporating, the quantity of cadmium in the remnant was determined by atomic absorption spectrophotometry. The reliability of such a technique was tested by studying as controls controls 17 days-old chick embryos injected with a known quantity of Cd(NO3). It showed no loss of cadmium. We also compared our procedure with a dry ashing method. The latter showed unacceptable losses and insufficient precision for the problems we wanted to investigate. Our method gave us much more precise results. The equipment we developed has functioned wholly satisfactorily and allowed us to investigate for instance cadmium distribution and concentration in embryonic organs of 17 days-old chicks. It could also be useful for researches concerning other biological samples analyzed for different heavy metals.View

Expand abstractDetermination of Total Tin in Environmental Biological and Water Samples by Atomic Absorption Spectrometry with Graphite FurnaceArticle

  • Feb 1980

Analysis of traces of tin using several analytical techniques (X-ray fluorescence, neutron activation, polarographic techniques and atomic absorption) have been tested. Parameters such as simplicity, rapidity, sensitivity and interferences are compared in order to choose the most useful method for practical purpose. Finally, flameless atomic absorption was chosen for the determination of total tin concentration in different natural samples. Digestion of biological samples (plant, plankton, fish, etc.) was achieved by using Lumatom (a trade organic chemical). Thus, the digested sample is directly injected into the graphite furnace. This digestion technique is suitable and rapid with a minimum of error (contamination and losses). For tin analysis in water samples, a preconcentration of tin is carried out by coprecipitation with 1, 10-phenanthroline and tetraphenyl boron. The precipitate is separated and dissolved in alcohol or in Lumatom. The sensitivity of this method is 0.1 ng absolute tin.View

Expand abstractRapid Separation on Copper Powder of Total Mercury in Blood and Determination of Mercury by Flameless Atomic Absorption SpectrometryArticle

  • Feb 1979

The determination of mercury in blood by flameless atomic absorption spectrometry (FAAS) has been described. Prior to its analysis, the sample was decomposed by combustion and separated on a copper powder micro-column. A special type of cell has been used which gives a better sensitivity compared with the types of cells described in the literature and the method of FAAS analysis has been improved. The sensitivity of 0.1 ng for 1% absorbance was observed and the standard deviation for six determinations at this level was found to be +/- 0.05 ng, for 95% probability.View

Expand abstractDetermination of Selenium and Arsenic in Animal Tissues with Platform Furnace Atomic Absorption Spectrometry and Deuterium Background CorrectionArticle

  • Feb 1986

Determination of selenium and arsenic in animal tissues is disturbed mainly by spectral interferences, uncorrectable with the dueterium arc. These interferences are produced by the calcium and magnesium phosphates always present in these matrixes. In animal tissue solution this disturbance may be avoided by addition of 20 micrograms of Ni (nitrate) for a 10 microliter sample. A lower amount of nickel does not allow a correct development of analyte absorbance signals whereas an excess induces a loss of sensitivity for the two elements studied. Measurement of peak-height proved to be most suitable, integrated absorbance being partially influenced by the matrix. The slope constants of working curves obtained with different animal matrixes are very close and direct calibration becomes possible. This was confirmed by analysis of several reference materials.View

Expand abstractDetermination of Trace Elements of Egyptian Cane Sugar (Naga Hammady Factories) by Neutron Activation, Atomic Absorption Spectrophotometric and Inductively Coupled Plasma-Atomic Emission Spectrometric AnalysesArticle

  • Feb 1984

INAA, AAS and ICP-AES techniques are applied to the determination of trace amounts of Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Eu, Fe, Ga, Hf, K, La, Li, Lu, Mg, Mn, Na, Nb, Ni, Pb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Th, Ti, U, V, W and Zn in the stalks of sugar cane plant after extracting juice, raw juice principal (mixed) juice, juice withdrawn from the successive stages of sugar industry, sirup, deposits from evaporators, molasse, A-? and B-sugar and in the soil samples (collected from the field supplying the factories by cane plants) taken from the immediate vicinity of the plant roots at surface, 30 and 60 cm depth. The results obtained are in a good agreement of the safety baselines of using juice as beverage, molasse derivatives (honey, sweets, …) as diet for common people in the developed countries and in industry (methanol, ethanol, acetone & acetic acid, …) and sugar sweeting for many purposes (in beverages, desserts, …). Differences of trace elements concentrations in soil samples may be reasoned to geochemical and biogeochemical fractionation while those in juice may be due to the changes in the environmental conditions, chemical composition and botanic structures. Variations in trace element contents in the products formed during the successive stages of sugar industry may be a result of evaporation, filtration processes, chemical treatments or corrosion of vessels, containers or engines. Trace elements are very important where they are responsible for enzymatic and biochemical reactions, matabolism, health and diseases.View

Expand abstractDetermination of Ultra Trace Amounts of Cobalt in Fish by Graphite Furnace Zeeman Effect Atomic Absorption SpectrometryArticle

  • Feb 1986

A method is described for determining stable cobalt concentrations in fish flesh and bone using polarized Zeeman effect graphite furnace atomic absorption spectrometry (ZAAS). Cobalt analysis on freshwater fish flesh samples (10 g dry weight) required predigestion and wet-ashing at 70-80 degrees C. Cobalt is chelated with ammonium pyrrolidine dithiocarbamate (APDC) extracted with methyl isobutyl ketone (MIBK) and analysed by ZAAS. The mean cobalt content calculated from the standard additions method using three replicate fish flesh samples was 4.23 +/- 1.0 microgram Co. Kg-1 (dry weight). Analyses were also carried out on flesh and bone samples from similar sized fish, of the same species, taken from three area lakes.View

Expand abstractAn Atomic Absorption Spectrophotometric Method for the Determination of Trace Amounts of Zinc in Canned Juices After Ion Exchange SeparationArticle

  • Feb 1984

An atomic absorption spectrophotometric method is described for the determination of microgram quantities of zinc in canned juices. After sample digestion in concentrated nitric acid, the solution is evaporated till near dryness, and then a solution of 2 M HCl is added to form tetrachlorozincate (II) ion. This acid solution, containing the zinc complex is passed through an ion-exchange column (anion exchange resin, chloride form, which is preconditioned by passing 1 M HCl solution). Zinc is eluted from the column with 0.01 M HCl solution. After evaporation to dryness, the residue is dissolved in 1% (v/v) HNO3, and then atomized into an air-acetylene flame. The limit of detection of the method is 0.15 micrograms ml-1 Zn. The analytical aspects of the proposed method, including the standard addition technique are discussed.View

Expand abstractDetermination of Cadmium in the Livers and Kidneys of Puffins by Carbon Furnace Atomic Absorption SpectrometryArticle

  • Feb 1976

A carbon furnace atomic absorption procedure is described for the determination of cadmium in the livers and kidneys of puffins, fratercula arctica. Samples are dried and weighed and 2 to 100 mg are dissolved in sulphuric and nitric acids. These solutions are analysed directly in the carbon furnace against aqueous standards and provide accurate results in the range 0-1 to 100 micrograms/g dry weight. The method is simple and rapid and requires much less of the small total sample than would be required for flame atomic absorption.View

Expand abstractDetermination of Arsenic in Urine and Feces by Dry Ashing, Atomic Absorption SpectrometryArticle

  • Feb 1980

A dry ashing flameless atomic absorption procedure was used to determine fish-arsenic in human urine and feces. Samples were dry ashed with Mg(NO3)2–MgO and dissolved in 6N HCl. Arsine was generated by the addition of NaBH4 and swept into a thermally heated silica tube furnace. Recoveries of several arsenic compounds added to samples ranged from 85 to 117%. The detection limit was about 3 ppb as for 10 g sample. Effects of the presence of common cations, anions and acids were studied.View

Expand abstractDetermination of “Heavy” Organotin Pollution of Water and Shellfish by a Modified Hydride Atomic Absorption ProcedureArticle

  • Feb 1986

Tin speciation in aquatic environment is very complex. To the natural SnIV and methylated compounds, human activities add mainly butylated, octylated, phenylated or even methylated derivatives. The most environmentally significant, due to their high toxicity and direct introduction in water through biocidal use, are the trisubstituted ones. Several sophisticated speciation procedures have been proposed, they are not susceptible of common use. We propose a simple and fast procedure allowing routine global distinction of “heavy” tin species that are most susceptible of exerting harmful effects. This AA method use the differences in volatility of stannanes generated by reduction with NaBH4. SnIV and the methylated species have very close response coefficients whereas “heavy” compounds respond very slightly at room temperature and are eliminated in a -40°C cold trap. “Heavy” tin determination in water is thus obtained by the difference between two hydride AA experiments, one performed on the untreated sample (“light tin”) and the other on a UV mineralised subsample (total tin). (The mineralisation of organotins is realised by UV irradiation–2 hours–in a quartz container–yields 95–100%.) The analysis of shellfish tissue relies also on two experiments. Total tin is measured on a mineralised sample and “light tin” is obtained on a subsample “solubilised” with an Ultra Turrax homogeneizer in a diluted HCl solution.View

Expand abstractThe Determination of Trace Transition Elements in Biological Tissues Using Flameless Atom Reservoir Atomic AbsorptionArticle

  • Jun 1973

The development of an analytical technique generally applicable to the determination of Ag, Cd, Co, Cu, Fe, Mn, Ni, Pb, V, and Zn in all biological tissues is described. All of these elements may readily be determined in tissue samples of less than 0.5 g using flameless atom reservoir atomic absorption with a Perkin-Elmer heated graphite atomizer. Some of the operational characteristics of this atomizer system are discussed. The utility of the method is illustrated by analyses of selected marine biota and of NBS standard orchard leaves.View

Expand abstractZeeman Effect Electrothermal Atomic Absorption Spectrophotometry with Matrix Modification for the Determination of Arsenic in UrineArticle

  • Feb 1983

Arsenic was determined in urine by electrothermal atomic absorption spectrophotometry using Zeeman Effect background correction and after matrix modification with 5% nickel nitrate. Mean recovery of urine samples spiked with 100 micrograms . L-1 dimethylarsinic acid was 97.9 micrograms . L-1. Within-run CV was 2.4%, between-run CV was 7.3% and the detection limit was determined to be 10.0 micrograms . L-1. The method can be used for the rapid screening of urine samples for elevated arsenic levels.View

Expand abstractDetermination of Selenium in Tissues, Serum, and Blood of Wild Rodents by Graphite Furnace Atomic Absorption SpectrophotometryArticle

  • Feb 1980

Selenium (Se) levels were determined in liver, kidney, blood, and serum of wild rodents using graphite furnace atomic absorption spectrophotometry. A simple wet digestion technique was used to prepare samples for analysis. Nickel nitrate was used to suppress volatilization of Se during the char stage. Compared to existing techniques this greatly reduces the effort and time required for sample preparation and allows use of the graphite furnace atomic absorption technique for Se determination.View

Expand abstractAtom Reservoir Atomic Absorption. Application to Marine Environmental SamplesArticle

  • Feb 1973

The application of flameless atom reservoir atomic absorption spectrophotometry to the analysis of trace metals in marine water, sediment and biota, and air particulate samples is discussed. Methods are described for the. analysis of a range of metals including Cu, Fe, Co, Ni, Cd, Ag, Zn, and Pb in these samples. Recent developments of atomizer design, primarily the static method of analysis and the grooved graphite tube are utilized, significantly improving the Sensitivities attainable and the speed of analysis.View

Expand abstractDetermination of Lead and Cadmium in Milk by Electrothermal Atomic Absorption SpectophotometryArticle

  • Feb 1987

The concentration of lead and cadmium in different kinds of milk samples (powdered, infant formula, market, buffalo, condensed and human) were determined using electrothermal atomic absorption spectrophotometric technique. Among all the varieties of milk analysed, condensed milk was found to contain much higher amount of lead. Human milk as expected was found to have lowest concentration of these elements. The results were compared with the reported values of other countries. Daily intake of these toxic elements by adults and babies up to the age of six months through the consumption of various types of milk was estimated and compared with the tolerance levels.View

Expand abstract[Analysis of atmospheric pollutants with coupled gas chromatography-atomic absorption or thermodesorption-gas chromatography].Article

  • Feb 1987

We have perfected a specific and original analytical method suitable for organic and inorganic compounds using sampled run-off water collected nearby a filling station. The dissolved lead species are volatilized by substituting the inorganic ligands with hydrogen, using sodium-borohydride in a suitable reaction medium (H2O2, KOH). The volatile lead hydrides are then trapped on a gas chromatographic column filled with Chromosorb W impregnated with 2% of OV 275 and immersed in liquid nitrogen. After desorption, the products are analysed by atomic absorption spectroscopy. We have carried out the analysis of aldehydes mixtures, sampled from a smog chamber. They are trapped, at room temperature, in a glass column filled with Tenax. These pollutants are then heated at 250 degrees C under a flow of nitrogen, and trapped again in a melted silica capillary column at -110 degrees C. This trapping being over, the column is drastically heated at 200 degrees C, which drives the products into the capillary column of a gas-chromatograph apparatus. This method has also enabled us to carry out a direct analysis of these pollutants sorbed on particles which have been placed into the glass column. this thermodesorption-gas chromatography system, coupled with a mass-spectrometry apparatus, allows us to identify and analyse most atmospheric pollutants.View

Expand abstractAtomic Absorption Spectrophotometric Determination of Microgram Quantities of Copper in Tea After Solvent ExtractionArticle

  • Feb 1985

An atomic absorption spectrophotometric method is described for determining trace amounts of copper in tea. The method is based on the solvent extraction of the metal as tetraiodocuprate (I), from 2 M HCl solutions of tea samples which contain 12% (w/v) KI, into methylisobutyl ketone. The organic extracts, containing the ion-association complex of copper are atomized into an air-acetylene flame. The limit of detection is 1.14 micrograms g-1 Cu.View

Expand abstractStudies on Lead Pollution: Atomic Absorption Spectrophotometric determination of lead in hair and teeth samplesArticle

  • Feb 1984

A simple, rapid and reliable method for the determination of lead in hair and teeth samples has been described. The method incorporates digestion of the samples by nitric acid followed by atomic absorption spectrophotometric determination of lead using 283.3 nm wavelength.View

Expand abstractExtraction Procedures for Atomic Absorption Spectrometric Analysis of Toxic Metals in Urban DustArticle

  • Feb 1983

A comparison has been made of eight acid extraction systems prior to the atomic absorption analysis of lead, nickel, copper, cadmium, cobalt, chromium, zinc, arsenic and mercury in street dust samples. Statistical treatment of the results enabled a valid comparison to be made in terms of overall extraction efficiency. For the purposes of carrying out large scale environmental surveys it was found that extraction with dilute nitric acid was the most suitable method. Analysis of the extracts by atomic absorption spectroscopy was shown to permit the accumulation of reliable data with the minimum requirement of apparatus and time.View

Expand abstractStudies on Mercury Pollution: Microdetermination of Mercury in Biological Materials by Cold Vapour Atomic Absorption SpectrometryArticle

  • Feb 1982

A simple, rapid, precise and accurate method for the determination of mercury in biological material is described. Biological samples were digested with nitric acid and acidified potassium permanganate and determined by cold vapour analyser. The proposed method was successfully employed for the determination of mercury in samples of fish, hair and blood.View

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Expand abstractA Comparative Determination of Heavy Metals in Moss Tissue by Atomic Absorption Spectroscopy, Differential Pulse Anodic Stripping Voltammetry, Direct Current Plasma Spectroscopy and X-ray Fluorescence SpectroscopyArticle

  • Feb 1987

Heavy metal contents of mosses are usually determined routinely for pollution studies, by atomic absorption spectroscopy. Results obtained from a such study are here compared with levels obtained from a comparative determination of the metals in the mosses by three other techniques: Differential pulse anodic stripping voltammetry (DPASV), Direct current plasma (atomic emission) spectroscopy (DCPS) and X-ray fluorescence (XRF) spectroscopy. The levels of Pb, Cu and Cd determined by DPASV did not differ significantly from those obtained from AAS. Metal levels from DCPS analyses tended to be significantly higher than the AAS values. Although the XRF values were slightly higher than those of AAS for Pb and Zn, the differences were statistically insignificant. The implication of these trends in comparing the extents of pollution in different regions, is highlighted.View

Expand abstractA Rapid, Routine Atomic Absorption Spectrometry Method for the Determination of Selenium at Sub-Microgram Levels in Animal TissueArticle

  • Feb 1974

A method is reported for determining selenium (Se) in animal tissue through Schöniger combustion, Se reduction to H2Se, and measurement by flame atomic absorption. The method provides several improvements over present hydrogen selenide generation apparatus and procedure. For the National Bureau of Standards Bovine Liver reference material containing 1.1±0.1 ppm Se, recovery averaged 100% with a relative standard deviation of 15 %. The minimum detecable quantity is 0.04 Ng Se. Data from the literature and results of analyses in our laboratory indicate that the method is adequately sensitive for tissue samples of almost any origin. Overall, our method is sensitive, precise, accurate, and simple and fast enough to use economically in routine monitoring of wildlife samples.View

Expand abstractDetermination of Cobalt in Bilogical Materials by Voltammetry and Electrothermal Atomic Absorption SpectrometryArticle

  • Feb 1984

For industrial purposes cobalt is used to a large extent. About 2,300 persons are occupationally exposed to this carcinogenic metal in Western Germany. As reliable analytic methods for biological monitoring are not available we developed procedures for analyzing cobalt in whole blood and urine by using two independent methods, voltammetry and ETAAS. For ETAAS-analysis of urine the cobalt content is chelatized and extracted in an organic solvent. This clean-up step enables us to calibrate with aqueous standards.–Samples of whole blood are directly injected into the graphite tube after being diluted with a homogeniziser. For their gentle thermal decomposition we use a temperature/time programme containing six steps. Both kinds of sample treatments are uncomplicated and permit routine applications. For voltammetric determination of cobalt in urine and blood the biological material must be completely mineralized. The dry residue is dissolved in a NH4Cl/NH3 solution. Cobalt is chelatized with 2,3-butanedione-dioxime and preconcentrated by adsorption at the hanging mercury electrode. By scanning the potential into negative direction the cobalt complex is reduced. The resulting signal can be used for the quantitative determination. For comparison of both methods we have analyzed blood and urine samples of occupationally exposed persons. We found very good correlations with a statistical significance at the level of 0.01%.View

Expand abstractElectron Donor-Acceptor Complexing Reagents for the Detection of Pesticides on TLCArticle

  • Mar 1972

The formation of π-complexes to detect and identify a representative group of carbamate, anilide and urea pesticides was investigated. Results obtained with several electron-acceptor reagents used by previous workers are compared with those obtained with a group of nitro-substituted fluorene derivatives. The pesticides studied were chosen for their potential ability to act as electron donors. Detection limits after thin-layer chromatography ranged from 0.5 to 5.0 micrograms, depending upon the strength of the complex formed. Various chromatographic systems were studied and applications of in situ reflectance spectroscopy and mass spectrometry were investigated. The method combines a reasonable sensitivity with good selectivity and the pesticide may be recovered from the complex for further study. This non-destructive method of analysis should be of particular use in the separation and identification of these pesticides and their metabolites.View

Expand abstractElectron donor-acceptor reagents in the analysis of pesticides. VII. A simple model system hydrolysis of some cardamate pesticidesArticle

  • Jun 1973

The decomposition of the carbamate insecticides carbaryl and Mobam and the herbicides IPC and CIPC in water at various pH’s was investigated. Analyses were performed in situ on silica-gel thin-layer chromatograms by reflectance spectroscopy after the developed chromatograms had been sprayed with the reagent CNTNF (9-dicyanomethylene-2,4,7-, trinitrofluorene) to form visible pi-complexes of the pesticides. Carbaryl and Mobam decomposed rapidly at basic pH’s but were stable in acid. IPC and CIPC were stable in water at pH’s tested.View

Expand abstractOrgano Chlorine Pesticides in Human Placenta and Accompanying FluidArticle

  • Feb 1980

Fifty specimens of placenta and accompanying fluid were collected at random from women of general population and analyzed for organo chlorine pesticides by gas liquid chromatograph using electron capture detector. BHC, Lindane, DDT, DDE, DDD and aldrin were detected in the placental tissue and accompanying fluid. Lindane, DDE and aldrin were more frequently detected. All the women were in their twenties but no correlation could be made between the compound and age, race or residence of the women. This is presumably the first attempt in India to detect the presence of pesticides in relation to their placental transfer, without occupational or accidental exposure.View

Expand abstractThe Accurate Measurement of Vanadium in Airborne ParticulatesArticle

  • Feb 1974

The accurate and rapid measurement of vanadium in airborne particulates is described, with particular reference to so-called high-volume air samples collected on glass fibre filters. The method involves the acid digestion of a part of the filter followed by analysis using atomic absorption spectroscopy (AA). The use of both conventional flame AA and AA with a graphite furnace atomizer was investigated.It was found that vanadium determinations are subject to large interferences from other elements when using the me mode. The elements Al, Si, Zn, K, and Na, which are present in fairly large concentrations in the sample, all gave an enhancement of the vanadium signal. The combined interference of the sample matrix was examined as a function of analyzing wavelength, burner height and vanadium Concentration.The use of the heated graphite atomizer removed all interferences from the system and lowered minimum detectable concentrations by two orders of magnitude. The glass fibre filter blank for vanadium was found to be below the detection limit. Minimum detectable vanadium concentrations, us& the graphite furnace, are 0.00025 mcg/m for an air sample of 2000 m.View

Expand abstractThe Accurate Measurement of Cadmium in Airborne ParticulatesArticle

  • Jun 1973

The accurate and rapid measurement of cadmium in airborne particulates is described, with particular reference to so-called high-volume air samples collected on glass fibre filters. The method involves the acid digestion of a part of the filter followed by analysis using atomic absorption spectroscopy. The use of both conventional flame atomic absorption and atomic absorption with a graphite furnace atomizer was investigated.It was found that the cadmium determinations were free of matrix error and that small interferences by other elements could be accurately taken into account. For a typical air sample of 2000 m, the cadmium amount can be determined with accuracy down to about 2 ng/m. Determinations below this level are possible at the expense, however, of the speed and simplicity of the method. The possibility of a non-uniform distribution of cadmium on the exposed filter, and the chance of accidental contamination of the filter or prepared sample by traces of cadmium are also discussed.View

Expand abstractEvaluation of Silica Gel Cartridges Coated In Situ with Acidified 2, 4-Dinitrophenylhydrazine for Sampling Aldehydes and Ketones in AirArticle

  • Feb 1986

A procedure for coating in situ silica gel in prepacked cartridges with 2,4-dinitrophenylhydrazine (DNPH) acidified with hydrochloric acid is described. The coated cartridge was compared with a validated DNPH impinger method for sampling organic carbonyl compounds (aldehydes and ketones) in diluted automotive exhaust emissions and in ambient air for subsequent analysis of the DNPH derivatives by high performance liquid chromatography. Qualitative and quantitative data are presented that show that the two sampling devices are equivalent. The coated cartridge is ideal for long-term sampling of carbonyls at sub to low parts-per-billion level in ambient air or for short-term sampling of carbonyls at low ppb to parts-per-million level in diluted automotive exhaust emissions. An unknown degradation product of acrolein has been tentatively identified as x-acrolein. The disappearance of acrolein in the analytical sample matrix correlates quantitatively almost on a mole for mole basis with the growth of x-acrolein. The sum of the concentration of acrolein and x-acrolein appears to be invariant with time.View

Expand abstractSingle Column Ion Chromatographic Determination of Inorganic Acids in Workroom PlacesArticle

  • Feb 1986

Single Column Ion Chromatography (SCIC) combines low capacity-columns, low conductivity eluents and a detector with considerable electronic supression capability and enables quantitation of ions at the ppm level without the need of a suppressor column associated with other forms of Ion Chromatography. Vapors and aerosols of inorganic acids are collected on filter and silica gel tubes and analyzed directly by SCIC. A conventional liquid chromatograph with a low capacity column and a conductimetric detector is used to analyze aerosols of Cl-, Br-, NO-3 and SO=4 with good results.View

Expand abstractDetermination of Gold and Platinum Traces in Biological Materials as a Part of a Multi-Element Radiochemical Activation Analysis SystemArticle

  • Feb 1984

For the analysis of human tissues for traces of gold and platinum–being used as constituents of therapeutic agents–a radiochemical neutron activation method has been developed. The radiochemical separation involves the selective removal of radioactive gold–formed by the reaction 197Au (n, gamma)198Au and the reaction 198Pt (n, gamma) 199Pt —- 199Au –as small metallic nuggets . The determination of gold and platinum is carried out as a part of an automated multi-element radiochemical separation scheme, allowing the determination of about 20 additional trace elements, and thus giving the possibility to study interelement relations. The analytical characteristics of the determination are evaluated. Gold and platinum levels measured in Bowen’s Kale, NBS Bovine Liver and NBS Orchard Leaves are presented. Values are shown for gold, platinum, and 20 other trace elements in various healthy and cancerous tissues from patients treated with cis-platin. (Cis-Diamminedichloroplatinum II).View

Expand abstractNeutron Activation Determination of Mercury in Waters after Preconcentration by Flotation of Dithizone–-Mercury ComplexesArticle

  • Feb 1985

Mercury in water samples, at levels below parts per billion, was collected by dithizone flotation. The statistical detection limit of Hg in seawater was 4 times better than that with a hydrous iron oxide–APDC flotation system in neutron activation determination. The same floated dithizone precipitate can be used repeatedly for collection from several volumes of the water sample. The Hg content in seawater was 0.017 micrograms/L. Average recovery from waters containing 0.025 micrograms/L, 0.05 micrograms/L and 0.1 micrograms/L was 98%. The method was applied successfully to the determination of Hg in NBS 1641b. Methyl mercury is also collected by the procedure described.View

Expand abstractDetermination of Trace Elements in Tea and Coffee by Neutron Activation AnalysisArticle

  • Sep 1971

Thermal neutron activation analysis, a high-resolution Ge(Li) gamma-ray spectrometer, and an IBM 360/67 digital computer were used to determine the concentration of Na, K, Sc, Cr, Mn, Fe, Co, Cu, Zn, Se, Br, Rb, Sb, Cs, and Hg in ground coffee and tea. This nondestructive multielement technique requires neither pre- nor postirradiation chemistry and eliminates problems of reagent contamination. The method is simple, precise and sensitive to 15 elements. Interferences from fast neutron (n, p) and (n, α) reactions are small and, if necessary, corrections may be applied easily. This technique can be applied to percolated tea and coffee.View

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Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed.

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International Journal of Environmental Analytical Chemistry | RG Journal Impact Rankings 2018 and 2019. Available from:[accessed Mar 19 2020].