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Sample records for lead isotope ratio

  1. Isotope ratios of lead as pollutant source indicators

    International Nuclear Information System (INIS)

    Chow, T.J.; Snyder, C.B.; Earal, J.L.

    1975-01-01

    Each lead ore deposit has its characteristic isotope ratios which are fixed during mineral ore genesis, and this unique property can be used to indicate the source of lead pollutants in the environment. The wolld production of primary lead is tabulated, and the geochemical significances of lead isotope ratios are discussed. The manufacture of lead alkyl additives for gasoline, which is the major source of lead pollutants, utilizes about 10% of the world annual consumption of lead. The isotope ratios of lead in gasoline, aerosols, soils and plants are correlated. Lead additives in various brands of gasoline sold in one region do not have the same isotope ratios. Regional variations in isotope ratios of lead additives were observed. This reflects the fact that petroleum refineries obtained the additives from various lead alkyl manufacturers which utilized lead from different mining districts. A definite changing trend of isotope ratios of lead pollutants in the San Diego, California (USA), area was detected. The lead shows a gradual increase in its radiogenic components during the past decade. This trend can be explained by the change of lead sources used by the additive manufacturers: Lead isotope ratios of the mid-1960's gasoline additives in the United States of America reflected those of less radiogenic leads imported from Canada, Australia, Peru and Mexico. Since then, the U.S. lead production has doubled-mainly from the Missouri district of highly radiogenic lead. Meanwhile, there has been a decrease in total lead imports. These combined effects result in changes in isotope ratios, from the less to more radiogenic, of the pooled lead. (aothor)

  2. Worldwide lead-isotope ratio in bivalves and sediments

    DEFF Research Database (Denmark)

    Larsen, Martin Mørk; Jacobsen, Gitte; Strand, Jakob

    The lead-isotope ratio have been used to assess and identify impact of leaded gasoline, coal combustion and  mineral activities[ref 1] due to the difference in 206Pb (~52%), 207Pb (~24%) and 208Pb (~23%) isotope ratios. The source of these differences is the decaying of the parent isotopes of 238U...

  3. Lead isotope ratios in artists' lead white: a progress report

    Energy Technology Data Exchange (ETDEWEB)

    Keisch, B; Callahan, R C [Carnegie-Mellon Univ., Pittsburgh, Pa. (USA)

    1976-07-01

    The lead isotope ratios in over four hundred samples of lead white have been determined. The samples represent various geographical sources and dates from the thirteenth century to the present. A new method for organizing this large volume of data is described which helps with the visualization of temporal and geographic patterns. A number of interesting relationships between lead isotope ratio and date or source are shown to exist. Some examples of successful applications of this methodology are described.

  4. Lead isotope ratios in artists' lead white: a progress report

    International Nuclear Information System (INIS)

    Keisch, B.; Callahan, R.C.

    1976-01-01

    The lead isotope ratios in over four hundred samples of lead white have been determined. The samples represent various geographical sources and dates from the thirteenth century to the present. A new method for organizing this large volume of data is described which helps with the visualization of temporal and geographic patterns. A number of interesting relationships between lead isotope ratio and date or source are shown to exist. Some examples of successful applications of this methodology are described. (author)

  5. Characterization of sources of lead in the urban air of Asia using ratios of stable lead isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Mukai, H.; Furuta, N.; Fujii, T.; Ambe, Y.; Sakamoto, K.; Hashimoto, Y. (National Institute of Environmental Studies, Tsukuba (Japan). Environmental Chemistry Division)

    1993-07-01

    Airborne particulate matter was collected at urban sites in six Asian countries (Japan, South Korea, China, Thailand, Sri Lanka, and Indonesia), and the stable lead isotope ratios were measured. Some source-related materials, such as coal and leaded gasoline, were also analyzed and compared to the ratios observed in airborne lead. Airborne lead isotope ratios differed considerably from each other, and these differences corresponded to differences in the regional source of lead. Leaded gasoline was still the primary source of lead in some cities in Asia, and the lead isotope ratios were strongly influenced by those of leaded gasoline. In Chinese and Korean cities, however, the considerable effect from coal combustion and industrial activity was also observed in their isotope ratios, despite leaded gasoline use. On the other hand, only refuse incineration was a possible single source of lead in Japanese air from the view of lead isotope ratios. 49 refs., 13 figs., 3 tabs.

  6. The isotopic composition of lead in man and the environment in Finland: isotope ratios of lead as indicators of pollutant source

    International Nuclear Information System (INIS)

    Keinonen, M.

    1989-01-01

    The isotopic composition of lead was determined in samples from the Helsinki area: in emission sources (gasoline, incinerator and lead smelter emissions, coal), in sources of intake to man (air, diet), in samples representing long-term deposition (lichen, soil, lake sediments) and in human tissue. The measurements of the isotope ratios 206 Pb/ 204 Pb and 206 Pb/ 207 Pb were done by thermal ionization mass spectrometry after chemical separation of lead by anion exchange and cathodic electrodeposition. The origin of lead in man and the environment in the Helsinki area was evaluated by using the differences in the measured isotope ratios as an indicator. The means of the ratios in gasoline ( 206 Pb/ 207 Pb 1.124+-0.026, 206 Pb/ 204 Pb 17.45+-0.42) and the ratios in other emission sources in Helsinki ( 206 Pb/ 207 Pb 1.149-1.226, 206 Pb/ 204 Pb 17.94-19.24) were significantly different. Lead in air samples from Helsinki (1.123+-0.013) could be attributed to gasoline, as lead in soil near a highway (1.136+-0.003). By contrast, isotope ratios measured in lichen (1.148+-0.006) indicated considerable amounts of lead from sources with higher 206 Pb abundances, evidently industrial sources. The isotope ratios in human liver, lung, and bone ( 206 Pb/ 207 Pb 1.142+-0.015, 1.151+-0.011, and 1.156+-0.013, respectively and 206 Pb/ 204 Pb 17.76+-0.28, 17.91+-0.20, and 17.96+-0.09, respectively) were practically the same and no significant dependence of the isotope ratios on age or concentration of lead was seen. In lake sediment cores a correlation was found between the isotope ratios, lead concentration, and depth. The non-anthropogenic lead of high isotope ratios from bedrock was the major component at depths dated older than 100 years. At the surface of the sediment atmospheric lead prevailed, with ratios similar to those of gasoline, air samples and lichen. In the post-1900 layers, anthropogenic lead made up about 40-60% of the total sedimentary lead

  7. Lead isotope ratios of ancient Chinese and Japanese glasses

    International Nuclear Information System (INIS)

    Yamasaki, Kazuo; Murozumi, Masayo; Nakamura, Seiji; Yuasa, Mitsuaki; Watarai, Motohiko.

    1980-01-01

    Lead isotope ratios of 29 archaeological glass samples (5 samples excavated in China, 10 samples excavated in Japan, and 14 samples made in Japan) were determined by surface ionization mass spectrometry with a HITACHI RMU-6 spectrometer. Of these glass samples, 28 were made of high lead glass, and one, of alkali-lime glass. Glass samples were decomposed in a mixture of hydrofluoric and nitric acids, and lead was separated from other elements by extraction with dithizone-chloroform. The lead nitrate solution thus prepared (corresponding to 0.5 μg Pb) was loaded on the rhenium single filament. The coefficients of variation of the determined ratios, 207 Pb/ 206 Pb and 208 Pb/ 206 Pb, were 0.1 -- 0.3%. Among the glasses excavated in Japan, some samples of the Yayoi period (ca. 3 rd C. B.C. -- ca. 3 rd C. A.D.) contained a large amount of barium in addition to lead, and resembled closely Chinese pre-Han glasses not only in chemical compositions, but also in lead isotope ratios. This means that pre-Han glasses were brought to Japan and then re-cast into glass beads characteristic of Japan. The lead isotope ratios of the glasses were compared with those of Chinese (2 samples), Korean (2) and Japanese (17) galena orea, and it was found that 12 glass beads made in the 8th century at Nara and 2 fine glass tubes made at Saga in the 18 th -- 19 th centuries showed similar lead isotope ratios with those of the Japanese galena ores. Consequently it is considered that the Japanese galena ores were already used as one of raw materials at manufacturing of these glass beads in ancient centuries. (author)

  8. The identification of lead ammunition as a source of lead exposure in First Nations: The use of lead isotope ratios

    International Nuclear Information System (INIS)

    Tsuji, Leonard J.S.; Wainman, Bruce C.; Martin, Ian D.; Sutherland, Celine; Weber, Jean-Philippe; Dumas, Pierre; Nieboer, Evert

    2008-01-01

    The use of lead shotshell to hunt water birds has been associated with lead-contamination in game meat. However, evidence illustrating that lead shotshell is a source of lead exposure in subsistence hunting groups cannot be deemed definitive. This study seeks to determine whether lead shotshell constitutes a source of lead exposure using lead isotope ratios. We examined stable lead isotope ratios for lichens, lead shotshell and bullets, and blood from residents of Fort Albany and Kashechewan First Nations, and the City of Hamilton, Ontario, Canada. Data were analyzed using ANOVA and regression analyses. ANOVA of isotope ratios for blood revealed significant differences with respect to location, but not sex. Hamilton differed from both Kashechewan and Fort Albany; however, the First Nations did not differ from each other. ANOVA of the isotope ratios for lead ammunition and lichens revealed no significant differences between lichen groups (north and south) and for the lead ammunition sources (pellets and bullets). A plot of 206 Pb/ 204 Pb and 206 Pb/ 207 Pb values illustrated that lichens and lead ammunition were distinct groupings and only the 95% confidence ellipse of the First Nations group overlapped that of lead ammunition. In addition, partial correlations between blood-lead levels (adjusted for age) and isotope ratios revealed significant (p 206 Pb/ 204 Pb and 206 Pb/ 207 Pb, and a significant negative correlation for 208 Pb/ 206 Pb, as predicted if leaded ammunition were the source of lead exposure. In conclusion, lead ammunition was identified as a source of lead exposure for First Nations people; however, the isotope ratios for lead shotshell pellets and bullets were indistinguishable. Thus, lead-contaminated meat from game harvested with lead bullets may also be contributing to the lead body burden

  9. Determination of stable isotope ratio of lead in airborne particulate matter by ICP-MS

    International Nuclear Information System (INIS)

    Mukai, Hitoshi; Ambe, Yoshinari

    1990-01-01

    ICP-MS was applied to the measurement of stable isotope ratios of lead, which are used as an indicator of the source of lead in airborne particulate matter. For the measurement of lead isotopes ratios, the influences of machine conditions, lead concentration and matrix elements to the precision and accuracy of the measurements were studied. At a scanning mode, dwell time of 40∼160 μs gave the best precision to the isotope ratio measurements; about 0.3 % of R.S.D. for 206 Pb/ 207 Pb and 206 Pb/ 208 Pb, 0.6 % for 206 Pb/ 204 Pb. Precision of the measurement was better at a high concentration of lead in sample solution. The observed value of 206 Pb/ 207 Pb ratio was not affected by the lead concentration, but in the cases of 206 Pb/ 204 Pb and 206 Pb/ 208 Pb, about 1 % of the value changed in the observed ratios with the lead concentration of 100∼500 μg/l. Six matrix elements (Na, K, Ca, Mg, Al, Fe) did not affect the observed isotope ratios up to 200 mg/l. The lead isotope ratios of reference materials {Urban Particulates (NIST) and Vehicle Exhausted Particulates (NIES)} were measured by using two kinds of sample; crude sample and lead-isolated sample from matrix elements by anodic deposition. Both cases gave the same isotope ratio values, therefore, lead isotope ratios in airborne particulate samples can be measured by ICP-MS without any separation of lead from matrix elements. (author)

  10. Lead isotope ratios in Japanese galena ores and archaeological objects

    International Nuclear Information System (INIS)

    Yamasaki, Kazuo; Murozumi, Masayo; Nakamura, Seiji; Hinata, Makoto; Yuasa, Mitsuaki.

    1978-01-01

    Lead isotope ratios 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, 208 Pb/ 204 Pb, 207 Pb/ 206 Pb and 208 Pb/ 206 Pb in Japanese galena ores and archaeological bronze objects were determined by a Hitachi RMU-6 mass spectrometer using a rhenium single filament as a surface ionization device. Basic experimental conditions including detection limit, fractionation effect, memory effect, etc. were examined, and the accuracy of determination was checked using the CIT shelf standard No. 1. Archaeological bronze objects were dissolved in nitric acid and lead was extracted by the dithizone method using specially purified reagents in a so-called clean laboratory. When 0.5 μg lead was loaded on the rhenium filament with phosphoric acid and silica gel as stabilizers, an ion current of 10 -13 -- 10 -15 A due to Pb + was obtained and maintained stable for several hours. Coefficients of variation found for the isotope ratios 207 Pb/ 206 Pb and 208 Pb/ 206 Pb were 0.1 -- 0.5%. Lead isotope ratios are given for 17 Japanese galena ores and for archaeological bronze objects such as bronze bells, halberds (Yayoi period), Horyuji pagoda spire (7th century), and Northern Sung coins (11th century). A close resemblance of the isotope ratios was found between Japanese galena ores and some Japanese bronze objects of the 7th century, suggesting the use of the former as raw materials of the latter. (auth.)

  11. Lead isotope ratio analysis of bullet samples by using quadrupole ICP-MS

    International Nuclear Information System (INIS)

    Tamura, Shu-ichi; Hokura, Akiko; Nakai, Izumi; Oishi, Masahiro

    2006-01-01

    The measurement conditions for the precise analysis of the lead stable isotope ratio by using an ICP-MS equipped with a quadrupole mass spectrometer were studied in order to apply the technique to the forensic identification of bullet samples. The values of the relative standard deviation obtained for the ratio of 208 Pb/ 206 Pb, 207 Pb/ 206 Pb and 204 Pb/ 206 Pb were lower than 0.2% after optimization of the analytical conditions, including the optimum lead concentration of the sample solution to be about 70 ppb and an integration time for 1 m/s of 15 s. This method was applied to an analysis of lead in bullets for rifles and handguns; a stable isotope ratio of lead was found to be suitable for the identification of bullets. This study has demonstrated that the lead isotope ratio measured by using a quadrupole ICP-MS was useful for a practical analysis of bullet samples in forensic science. (author)

  12. Studies in the determination of lead isotope ratios by inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Date, A.R.; Yuk Ying Cheung

    1987-01-01

    The application of ICP-MS to the determination of lead isotope ratios in geological materials is described. Data presented for a series of lead mineral concentrates are compared with reference values obtained by conventional solid source thermal ionisation mass spectrometry. The simultaneous determination of lead isotope ratios and trace elements is carried out in a rapid analysis mode. The application of an electrothermal vaporisation technique for small solution aliquots is described. Lead isotope ratio data for the United States Geological Survey standard reference silicate rock BCR-1, obtained without separation of lead from the matrix, are compared with previously published values obtained after separation. (author)

  13. Lead isotope ratios as a tracer for lead contamination sources: A lake Andong case study

    Directory of Open Access Journals (Sweden)

    Kim Y. H

    2013-04-01

    Full Text Available The objective of this study was to evaluate stable Pb isotope signatures as a tracer for Pb contamination in Lake Andong. For Pb isotope analysis, we collected water and sediment from Lake Andong, particles in the air, soils, and stream water, mine tailings, sludge and wastewater from zinc smelting around lake Andong watershed. The results showed that Pb isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb for zinc concentrate were 18.809 ± 0.322, 15.650 ± 0.062, and 38.728 ± 0.421, respectively. In wastewater, isotopic ratio values (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb were 17.363 ± 0.133, 15.550 ± 0.025, and 37.217 ± 0.092, respectively. Additionally, isotopic ratio values (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb for sludge were 17.515 ± 0.155, 15.537 ± 0.018, and 37.357 ± 0.173, respectively. These values were similar to those in zinc and lead concentrate originated from Canada and South America. In contrast, Pb isotope ratios of soil, tailings and sediment from Lake Andong were similar to those of Korean ore. Atmospheric particles showed different patterns of Pb isotope ratios from sediments, soils, and zinc smelting and this needs further investigation in order to identify atmospheric Pb sources.

  14. Tracing lead pollution sources in abandoned mine areas using stable Pb isotope ratios.

    Science.gov (United States)

    Yoo, Eun-Jin; Lee, Jung-A; Park, Jae-Seon; Lee, Khanghyun; Lee, Won-Seok; Han, Jin-Seok; Choi, Jong-Woo

    2014-02-01

    This study focused on Pb isotope ratios of sediments in areas around an abandoned mine to determine if the ratios can be used as a source tracer. For pretreatment, sediment samples were dissolved with mixed acids, and a multi-collector inductively coupled plasma mass spectrometer (MC-ICP-MS, Nu plasma II) was used to investigate the Pb isotopic composition of the samples. The measured isotope ratios were then corrected for instrumental mass fractionation by measuring the (203)Tl/(205)Tl ratio. Repeated measurements with the NIST SRM 981 reference material showed that the precision of all ratios was below 104 ppm (±2σ) for 50 ng/g. The isotope ratios ((207)Pb/(206)Pb) found were 0.85073 ± 0.0004~0.85373 ± 0.0003 for the main stream, while they were 0.83736 ± 0.0010 for the tributary and 0.84393 ± 0.0002 for the confluence. A binary mixing equation for isotope ratios showed that the contributions of mine lead to neighboring areas were up to 60%. Therefore, Pb isotope ratios can be a good source tracer for areas around abandoned mines.

  15. Bone lead levels and lead isotope ratios in red grouse from Scottish and Yorkshire moors

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, Vernon G., E-mail: vthomas@uoguelph.ca [Department of Integrative Biology, College of Biological Science, University of Guelph, Guelph, Ontario, N1G 2W1 (Canada); Scheuhammer, Anton M.; Bond, Della E. [Metals Toxicology Laboratory, National Wildlife Research Centre, Carleton University, Ottawa, Ontario, K1A 0H3 (Canada)

    2009-05-15

    Leg and foot bones of adult and juvenile red grouse (Lagopus lagopus scoticus) were collected from hunter-shot birds on two Scottish estates (Glendye and Invermark) and one Yorkshire estate in September, 2003. The lead content of bones was measured by atomic absorption spectrophotometry, and corresponding stable lead isotopes (Pb204, 206, 207, 208) by inductively coupled plasma mass spectrometry. At the Glendye (N = 111) and Invermark (N = 85) estates, relatively few birds (5.4% and 3.5%, respectively) had highly elevated bone lead concentrations (> 20 mug/g dry weight). In bones of these highly exposed birds, a combination of Pb206:Pb207 and Pb208:Pb207ratios was consistent with ingestion of lead gunshot available in Europe. By contrast, Yorkshire grouse experienced a high incidence (65.8%) of bone lead > 20 mug/g. The Pb206:Pb207 and Pb208:Pb207ratios in bones of these highly exposed birds were consistent with a combined exposure to ingested lead gunshot and lead from galena mining in the region. Lead isotope ratios also indicated that lead from UK gasoline combustion and fallout from atmospheric particles was not a likely source of elevated lead in bones of either Scottish or Yorkshire grouse. Suggested management options for the three moors include adopting nontoxic shot for all game shooting on the estates, allowing heather (Calluna vulgaris) vegetation to grow tall in lead shot fall-out zones to reduce physical access to high densities of lead shot already present, and provision of calcareous grit across moors to reduce lead assimilation from all ingested sources of lead.

  16. Bone lead levels and lead isotope ratios in red grouse from Scottish and Yorkshire moors

    International Nuclear Information System (INIS)

    Thomas, Vernon G.; Scheuhammer, Anton M.; Bond, Della E.

    2009-01-01

    Leg and foot bones of adult and juvenile red grouse (Lagopus lagopus scoticus) were collected from hunter-shot birds on two Scottish estates (Glendye and Invermark) and one Yorkshire estate in September, 2003. The lead content of bones was measured by atomic absorption spectrophotometry, and corresponding stable lead isotopes (Pb204, 206, 207, 208) by inductively coupled plasma mass spectrometry. At the Glendye (N = 111) and Invermark (N = 85) estates, relatively few birds (5.4% and 3.5%, respectively) had highly elevated bone lead concentrations (> 20 mug/g dry weight). In bones of these highly exposed birds, a combination of Pb206:Pb207 and Pb208:Pb207ratios was consistent with ingestion of lead gunshot available in Europe. By contrast, Yorkshire grouse experienced a high incidence (65.8%) of bone lead > 20 mug/g. The Pb206:Pb207 and Pb208:Pb207ratios in bones of these highly exposed birds were consistent with a combined exposure to ingested lead gunshot and lead from galena mining in the region. Lead isotope ratios also indicated that lead from UK gasoline combustion and fallout from atmospheric particles was not a likely source of elevated lead in bones of either Scottish or Yorkshire grouse. Suggested management options for the three moors include adopting nontoxic shot for all game shooting on the estates, allowing heather (Calluna vulgaris) vegetation to grow tall in lead shot fall-out zones to reduce physical access to high densities of lead shot already present, and provision of calcareous grit across moors to reduce lead assimilation from all ingested sources of lead.

  17. Isotopic ratio based source apportionment of children's blood lead around coking plant area.

    Science.gov (United States)

    Cao, Suzhen; Duan, Xiaoli; Zhao, Xiuge; Wang, Beibei; Ma, Jin; Fan, Delong; Sun, Chengye; He, Bin; Wei, Fusheng; Jiang, Guibin

    2014-12-01

    Lead exposure in the environment is a major hazard affecting human health, particularly for children. The blood lead levels in the local children living around the largest coking area in China were measured, and the source of blood lead and the main pathways of lead exposure were investigated based on lead isotopic ratios ((207)Pb/(206)Pb and (208)Pb/(206)Pb) in blood and in a variety of media, including food, airborne particulate matter, soil, dust and drinking water. The children's blood lead level was 5.25 (1.59 to 34.36 as range) μg dL(-1), lower than the threshold in the current criteria of China defined by the US Centers for Disease Control (10 μg dL(-1)). The isotopic ratios in the blood were 2.111±0.018 for (208)Pb/(206)Pb and 0.864±0.005 for (207)Pb/(206)Pb, similar to those of vegetables, wheat, drinking water, airborne particulate matter, but different from those of vehicle emission and soil/dust, suggesting that the formers were the main pathway of lead exposure among the children. The exposure pathway analysis based on the isotopic ratios and the human health risk assessment showed that dietary intake of food and drinking water contributed 93.67% of total exposed lead. The study further indicated that the coal used in the coking plant is the dominant pollution source of lead in children's blood. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Chemical compositions and lead isotope ratios of ancient lead-barium glasses found in Japan

    International Nuclear Information System (INIS)

    Yamasaki, Kazuo.

    1991-01-01

    Six lead-barium glasses found in the archaeological sites of the Yayoi period in the northern part of Kyushu, Japan were chemically analysed and their lead isotope ratios were determined. These data agreed with those of the glasses of the Pre-Han period found in China, suggesting the presence of possible trade between China in the Pre-Han Period (ca. fourth-third centuries B.C.) and Japan in the earlier Yayoi period (ca. first century B.C.). (author)

  19. Effectiveness of leaded petrol phase-out in Tianjin, China based on the aerosol lead concentration and isotope abundance ratio

    International Nuclear Information System (INIS)

    Wang Wan; Liu Xiande; Zhao Liwei; Guo, Dongfa; Tian Xiaodan; Adams, Freddy

    2006-01-01

    The phase-out of leaded petrol has been a measure widely used to reduce atmospheric lead pollution. Since the 1980s, China began to promote unleaded petrol. In order to assess the effectiveness of the measure an isotope fingerprint technique was applied for aerosol samples in the city of Tianjin. After dilute acid leaching, the lead concentration and isotope abundance ratios were determined for 123 samples collected in Tianjin during eight years (1994-2001). The 206 Pb / 207 Pb ratio was lower in summer, when coal combustion emission was low and vehicle exhaust became more important, indicating that the 206 Pb / 207 Pb ratio of leaded petrol in Tianjin is lower than that of aerosol samples. The 206 Pb / 207 Pb ratio gradually increased from 1994 to 2001, a trend that suggests that the contribution from vehicle exhaust was diminishing. Overall, the measurements matched well with national statistical data of leaded and unleaded petrol production. After the nationwide switch to unleaded gasoline, comprehensive control measures are urgently needed to reduce air lead pollution in China, as aerosol lead reduced slightly but remains at a relatively high level

  20. Lead isotope ratios of galenas from the Hida area

    International Nuclear Information System (INIS)

    Sato, Kazuo; Sasaki, Akira; Akiyama, Shin-ichi; Konagai, Kenji.

    1978-01-01

    Ore lead isotope data of the Kamioka and nearby lead-zinc mineralizations in the Hida metamorphic terrain are variable. Small but distinct isotopic variation is observed even in a single ore deposit. The present site of the Hida metamorphic terrain once was occupied by a Precambrian continent. The leads from the metamorphic, plutonic and sedimentary rocks indicate such continental nature of this terrain, as they have more complex isotopic patterns than those observed in the leads from igneous rocks and ores in younger terrains in Japan. The variability of ore lead isotopes in the Hida area could also be related to the presence of the old basement structure, implying that the leads in the Kamioka and nearby ore deposits came from more than a source of material. (mori, K.)

  1. Measurements of total lead concentrations and of lead isotope ratios in whole blood by use of inductively coupled plasma source mass spectrometry

    International Nuclear Information System (INIS)

    Delves, H.T.; Campbell, M.J.

    1988-01-01

    Methods are described for the accurate and precise determination of total lead and its isotopic composition in whole blood using inductively coupled plasma source mass spectrometry (ICP-MS). Sensitivities of up to 3 x 10 6 counts s -1 for 208 Pb at a total lead concentration of 5 μmol l -1 (1 μg ml -1 ) enabled total blood lead levels to be measured in 4 min per sample, with a detection limit of 0.072 μmol l -1 (15 μg l -1 ). The agreement between ICP-MS and atomic absorption spectrometry (AAS) for this analysis was excellent: ICP-MS 0.996 x AAS -0.0165 μmol l -1 ; r 0.994. Isotope ratio measurements required 15 min to achieve the required accuracy and precision both of which were generally better than 0.5% for 206 Pb: 207 Pb and 208 Pb: 206 Pb isotopic lead ratios. The ICP-MS data for these ratios in ten quality control blood specimens has a mean bias relative to isotope dilution mass spectrometry of -0.412% for 206 Pb: 207 Pb ratios and of +0.055% for the 208 Pb: 206 Pb ratios. This level of accuracy and that of the total blood lead measurements is sufficient to permit application of these ICP-MS methods to environmental studies. (author)

  2. Determination of strontium and lead isotope ratios of grains using high resolution inductively coupled plasma mass spectrometer with single collector

    International Nuclear Information System (INIS)

    Shinozaki, Miyuki; Ariyama, Kaoru; Kawasaki, Akira; Hirata, Takafumi

    2010-01-01

    A method for determining strontium and lead isotope ratios of grains was developed. The samples investigated in this study were rice, barley and wheat. The samples were digested with nitric acid and hydrogen peroxide, and heated in a heating block. Strontium and lead were separated from the matrix by adding an acid digested solution into a column packed with Sr resin, which has selectivity for the absorption of strontium and lead. Strontium and lead isotope ratios were determined using a high-resolution inductively coupled plasma mass spectrometer (HR-ICP-MS) with a single collector. The intraday relative standard deviations of 87 Sr/ 86 Sr and lead isotope ratios ( 204 Pb/ 206 Pb, 207 Pb/ 206 Pb, 208 Pb/ 206 Pb) by HR-ICP-MS measurements were < 0.06% and around 0.1%, respectively. This method enabled us to determine strontium and lead isotope ratios in two days. (author)

  3. Biological fractionation of lead isotopes in Sprague-Dawley rats lead poisoned via the respiratory tract.

    Directory of Open Access Journals (Sweden)

    Jing Wu

    Full Text Available It was considered that lead isotope ratios did not change during physical, chemical, or biological processes. Thus, lead isotope ratios have been used as fingerprints to identify possible lead sources. However, recent evidence has shown that the lead isotope ratios among different biological samples in human are not always identical from its lead origins in vitro. An animal experiment was conducted to explore the biological fractionation of lead isotopes in biological systems.24 male Sprague-Dawley (SD rats were divided into groups that received acute lead exposure (0, 0.02, 0.2, or 2 mg/kg body weight of lead acetate via the respiratory route every day for 5 days. Biological samples (i.e., blood, urine, and feces were collected for comparison with the lead acetate (test substance and the low-lead animal feed (diet administered to the rats. The lead isotope ratios were determined by inductively coupled plasma mass spectrometry (ICP-MS.There are significant differences (p<0.05 in lead isotope ratios between blood, urine, and feces. Moreover, a nonlinear relationship between the blood lead concentration and the blood lead isotope ratios was observed. There is also a threshold effect to the fractionation function. Only the blood isotope ratio of (204Pb/(206Pb matches the test substance well. As for feces, when (204Pb/(206Pb ratio is considered, there is no significant difference between feces-test substance pairs in medium and high dose group.The biological fractionation of lead isotopes in SD rats was observed. Moreover, there might be a threshold for the biological fractionation of lead isotopes which is depending on whole blood lead level. It is considered to be more reliable that we compared the isotope ratios of potential lead hazards with both blood and feces lead fingerprints especially for (204Pb/(206Pb ratio under high-dose exposure.

  4. Ore lead isotope ratios in a continually changing Earth

    International Nuclear Information System (INIS)

    Cumming, G.L.; Richards, J.R.

    1975-01-01

    A critical reassessment of the construction of simple ore lead isotopic development curves is followed by three fresh approximations, all designed to involve the minimum possible number of assumptions. All are based on the Russell-Reynolds algorithm, when in its simplest form involves knowledge only of ratios, not of ages. The calculations are applied to a restricted class of ore leads, and the latest constant values for the U and Th isotopes are employed. Model I treats all data as being of equal weight, and shows that the deletion or inclusion of the Canyon Diablo meterorite data makes no difference to the derived parameters. Model II demonstrates that essentially the same parameters result if the simple curve is forced through the meteorite point; i.e. questions about homogeneity or otherwise of 'initial terrestrial'Pb are unimportant to the regression . Model III makes allowance for the known discrepancy in young 'model ages' by providing for a steady linear change in U/Pb and Th/Pb. The additional assumption of one fixed time point proves necessary. An age close to 430 m.y.for Captains Flat, N.S.W., yields acceptable age estimates for most other deposits investigated. No claim is made for the uniquences of this solution, but the derived evidence for steady growth in U/Ph accompanied by a slight decline in Th/U seems compatible with a crustal source for the lead ores concerned. (Auth.)

  5. Lead isotopic compositions of environmental certified reference materials for an inter-laboratory comparison of lead isotope analysis

    International Nuclear Information System (INIS)

    Aung, Nyein Nyein; Uryu, Tsutomu; Yoshinaga, Jun

    2004-01-01

    Lead isotope ratios, viz. 207 Pb/ 206 Pb and 208 Pb/ 206 Pb, of the commercially available certified reference materials (CRMs) issued in Japan are presented with an objective to provide a data set, which will be useful for the quality assurance of analytical procedures, instrumental performance and method validation of the laboratories involved in environmental lead isotope ratio analysis. The analytical method used in the present study was inductively coupled plasma quadrupole mass spectrometry (ICPQMS) presented by acid digestion and with/without chemical separation of lead from the matrix. The precision of the measurements in terms of the relative standard deviation (RSD) of triplicated analyses was 0.19% and 0.14%, for 207 Pb/ 206 Pb and 208 Pb/ 206 Pb, respectively. The trueness of lead isotope ratio measurements of the present study was tested with a few CRMs, which have been analyzed by other analytical methods and reported in various literature. The lead isotopic ratios of 18 environmental matrix CRMs (including 6 CRMs analyzed for our method validation) are presented and the distribution of their ratios is briefly discussed. (author)

  6. Biological fractionation of lead isotopes in Sprague-Dawley rats lead poisoned via the respiratory tract.

    Science.gov (United States)

    Wu, Jing; Liu, Duojian; Xie, Qing; Wang, Jingyu

    2012-01-01

    It was considered that lead isotope ratios did not change during physical, chemical, or biological processes. Thus, lead isotope ratios have been used as fingerprints to identify possible lead sources. However, recent evidence has shown that the lead isotope ratios among different biological samples in human are not always identical from its lead origins in vitro. An animal experiment was conducted to explore the biological fractionation of lead isotopes in biological systems. 24 male Sprague-Dawley (SD) rats were divided into groups that received acute lead exposure (0, 0.02, 0.2, or 2 mg/kg body weight of lead acetate) via the respiratory route every day for 5 days. Biological samples (i.e., blood, urine, and feces) were collected for comparison with the lead acetate (test substance) and the low-lead animal feed (diet) administered to the rats. The lead isotope ratios were determined by inductively coupled plasma mass spectrometry (ICP-MS). There are significant differences (pblood, urine, and feces. Moreover, a nonlinear relationship between the blood lead concentration and the blood lead isotope ratios was observed. There is also a threshold effect to the fractionation function. Only the blood isotope ratio of (204)Pb/(206)Pb matches the test substance well. As for feces, when (204)Pb/(206)Pb ratio is considered, there is no significant difference between feces-test substance pairs in medium and high dose group. The biological fractionation of lead isotopes in SD rats was observed. Moreover, there might be a threshold for the biological fractionation of lead isotopes which is depending on whole blood lead level. It is considered to be more reliable that we compared the isotope ratios of potential lead hazards with both blood and feces lead fingerprints especially for (204)Pb/(206)Pb ratio under high-dose exposure.

  7. Lead isotope ratios in tree bark pockets: an indicator of past air pollution in the Czech Republic.

    Science.gov (United States)

    Conkova, M; Kubiznakova, J

    2008-10-15

    Tree bark pockets were collected at four sites in the Czech Republic with differing levels of lead (Pb) pollution. The samples, spanning 1923-2005, were separated from beech (Fagus sylvatica) and spruce (Picea abies). Elevated Pb content (0.1-42.4 microg g(-1)) reflected air pollution in the city of Prague. The lowest Pb content (0.3-2.6 microg g(-1)) was found at the Kosetice EMEP "background pollution" site. Changes in (206)Pb/(207)Pb and (208)Pb/(206)Pb isotope ratios were in agreement with operation times of the Czech main anthropogenic Pb sources. Shortly after the Second World War, the (206)Pb/(207)Pb isotope ratio in bark pockets decreased from 1.17 to 1.14 and the (208)Pb/(206)Pb isotope ratio increased from 2.12 to 2.16. Two dominant emission sources responsible for these changes, lignite and leaded petrol combustion, contributed to the shifts in Pb isotope ratios. Low-radiogenic petrol Pb ((206)Pb/(207)Pb of 1.11) lead to lower (206)Pb/(207)Pb in bark pockets over time. High-radiogenic lignite-derived Pb ((206)Pb/(207)Pb of 1.18 to 1.19) was detected in areas affected by coal combustion rather than by traffic.

  8. A lead isotope ratio data base of ancient Chinese bronzes

    International Nuclear Information System (INIS)

    Jin Zhengyao

    2005-01-01

    A data base of lead isotope ratio of ancient Chinese bronzes is set up. There are 2888 members, including bronze objects, casting remains, and related ores, etc. in the file. The file contents of data base are made from analysis work on Chinese bronze previously carried out in several laboratories in China, Japan and USA. The main body of the file contents is formed from records, analysis data, reference documents, and images. The data base is designed for sharing information in provenance study on raw metal material for bronze production in China Bronze Age. (author)

  9. Characteristics of lead isotope ratios and elemental concentrations in PM 10 fraction of airborne particulate matter in Shanghai after the phase-out of leaded gasoline

    Science.gov (United States)

    Zheng, Jian; Tan, Mingguang; Shibata, Yasuyuki; Tanaka, Atsushi; Li, Yan; Zhang, Guilin; Zhang, Yuanmao; Shan, Zuci

    The stable lead (Pb) isotope ratios and the concentrations of 23 elements, including heavy metals and toxic elements, were measured in the PM 10 airborne particle samples collected at seven monitoring sites in Shanghai, China, to evaluate the current elemental compositions and local airborne Pb isotope ratio characteristics. Some source-related samples, such as cement, coal and oil combustion dust, metallurgic dust, vehicle exhaust particles derived from leaded gasoline and unleaded gasoline, and polluted soils were analyzed for their Pb content and isotope ratio and compared to those observed in PM 10 samples. Airborne Pb concentration ranged from 167 to 854 ng/m 3 in the seven monitored sites with an average of 515 ng/m 3 in Shanghai, indicating that a high concentration of Pb remains in the air after the phasing out of leaded gasoline. Lead isotopic compositions in airborne particles ( 207Pb/ 206Pb, 0.8608±0.0018; 208Pb/ 206Pb, 2.105±0.005) are clearly distinct from the vehicle exhaust particles ( 207Pb/ 206Pb, 0.8854±0.0075; 208Pb/ 206Pb, 2.145±0.006), suggesting that the automotive lead is not currently the major component of Pb in the air. By using a binary mixing equation, a source apportionment based on 207Pb/ 206Pb ratios, indicates that the contribution from automotive emission to the airborne Pb is around 20%. The Pb isotope ratios obtained in the source-related samples confirmed that the major emission sources are metallurgic dust, coal combustion, and cement.

  10. Using Lead Concentrations and Stable Lead Isotope Ratios to Identify Contamination Events in Alluvial Soils

    International Nuclear Information System (INIS)

    Saint-Laurent, D.; St-Laurent, J.; Hahni, M.; Chapados, C.; Ghaleb, B.

    2010-01-01

    Soils contaminated with hydrocarbons (C10,C50), polycyclic aromatic hydrocarbons (PAHs), and other contaminants (e.g., As, Cd, Cu, Pb) were recently discovered on the banks of the Saint-Francois and Massawippi rivers. Alluvial soils are contaminated over a distance of 100 kilometers, and the level of the contaminated-hydrocarbon layer in the soil profiles is among the highest at the Windsor and Richmond sites. Concentrations of lead and stable lead isotope ratios ( 204 Pb/ 206 Pb, 206 Pb/ 207 Pb, 208 Pb/ 20 '6Pb) are also used to identify contamination events. The maximum and minimum values detected in soil profiles for arsenic, cadmium, and lead vary from 3.01 to 37.88?mg kg -1 (As), 0.11 to 0.81?mg kg-1 (Cd) 12.32 to 149.13?mg kg -1 (Pb), respectively, while the 207 Pb/ 206 Pb isotopic ratio values are between 0.8545 and 0.8724 for all the profiles. The highest values of trace elements (As, Pb and Zn) were detected in the hydrocarbon layer (C10,C50), most often located at the bottom of the profiles (160, 200, and 220 cm in depth). The various peaks recorded in the soils and the position of the profiles suggest that various contaminants were transported by the river on several occasions and infiltrated the soil matrix or deposited on flood plains during successive floods. Atmospheric particles which entered the river or deposited on riverbanks must also be considered as another source of pollution recorded in soils

  11. Using Lead Concentrations and Stable Lead Isotope Ratios to Identify Contamination Events in Alluvial Soils

    Directory of Open Access Journals (Sweden)

    Diane Saint-Laurent

    2010-01-01

    Full Text Available Soils contaminated with hydrocarbons (C10–C50, polycyclic aromatic hydrocarbons (PAHs, and other contaminants (e.g., As, Cd, Cu, Pb were recently discovered on the banks of the Saint-François and Massawippi rivers. Alluvial soils are contaminated over a distance of 100 kilometers, and the level of the contaminated-hydrocarbon layer in the soil profiles is among the highest at the Windsor and Richmond sites. Concentrations of lead and stable lead isotope ratios (204Pb/206Pb, 207Pb/206Pb, 208Pb/206Pb are also used to identify contamination events. The maximum and minimum values detected in soil profiles for arsenic, cadmium, and lead vary from 3.01 to 37.88 mg kg-1 (As, 0.11 to 0.81 mg kg-1 (Cd 12.32 to 149.13 mg kg-1 (Pb, respectively, while the 207Pb/206Pb isotopic ratio values are between 0.8545 and 0.8724 for all the profiles. The highest values of trace elements (As, Pb and Zn were detected in the hydrocarbon layer (C10–C50, most often located at the bottom of the profiles (160, 200, and 220 cm in depth. The various peaks recorded in the soils and the position of the profiles suggest that various contaminants were transported by the river on several occasions and infiltrated the soil matrix or deposited on floodplains during successive floods. Atmospheric particles which entered the river or deposited on riverbanks must also be considered as another source of pollution recorded in soils.

  12. Selection of mode for the measurement of lead isotope ratios by inductively coupled plasma mass spectrometry and its application to milk powder analysis

    International Nuclear Information System (INIS)

    Dean, J.R.; Ebdon, L.; Massey, R.

    1987-01-01

    An investigation into the selection of the optimum mode for the measurement of isotope ratios in inductively coupled plasma mass spectrometry (ICP-MS) is reported, with particular reference to lead isotope ratios. Variation in the accuracy and precision achievable using the measurement modes of scanning and peak jumping are discussed. It is concluded that if sufficient sample and time are available, scanning gives best accuracy and precision. Isotope dilution analysis (IDA) has been applied to the measurement of the lead content of two dried milk powders of Australian and European origin introduced as slurries into ICP-MS. Differences in the lead isotope ratios in the two milk powders were investigated and the total lead content determined by IDA. Isotope dilution analysis permitted accurate data to be obtained with an RSD of 4.2% or milk powder containing less than 30 ng g -1 of lead. The ICP-MS technique is confirmed as a useful tool for IDA. (author)

  13. Stable lead isotope ratios and metals in freshwater mussels from a uranium mining environment in Australia’s wet-dry tropics

    International Nuclear Information System (INIS)

    Bollhöfer, Andreas

    2012-01-01

    Highlights: ► Lead isotope ratios in mussels from Magela more uranogenic than from Sandy catchment. ► Additional input of Broken Hill type lead further downstream of mine site. ► Lead isotope ratios in mussels ideal for source apportionment of lead into waterways. - Abstract: Concentrations of Fe, Mn, Cu, Zn, U and Pb, and stable Pb isotopes 206 Pb, 207 Pb and 208 Pb were measured via inductively coupled plasma mass spectrometry in sediments, water and freshwater mussels (Velesunio angasi) from two catchments in the Alligator Rivers Region, Australia. Sediment U and Pb concentrations were higher in Magela Creek downstream than upstream of the Ranger U mine due to the mineralised nature of the catchment and potential local input of sediment from the mine site. Water metal concentrations were highest in Georgetown Creek, which is a tributary of Magela Creek and part drains the Ranger mine site, but there was little difference in concentrations between the Magela Creek upstream and downstream sites. Metal concentrations in mussels collected immediately upstream and downstream of the mine site also showed little difference, whereas Pb isotope ratios displayed a very distinct pattern. The 206 Pb/ 207 Pb and 208 Pb/ 207 Pb isotope ratios were more uranogenic downstream than upstream of the site and also more uranogenic than ratios measured in Sandy Billabong, a reference billabong in a catchment not influenced by U mineralisation. Isotope ratios were also more uranogenic in younger mussels, potentially due to the increasing footprint of the mine site over the past decade. The most uranogenic ratios were found in mussels from Georgetown Creek and at a site approximately 2 km downstream. At Mudginberri Billabong, approximately 12 km downstream of the Ranger mine, the relative contribution of uranogenic Pb to the total Pb concentration in mussels was small and overwhelmed by the input of industrial Pb with a Broken Hill type Pb signature. Whereas metal uptake by and

  14. Recent development in isotope ratio mass spectrometry

    International Nuclear Information System (INIS)

    Platzner, I.

    1992-01-01

    Within the limited of this review the following topics will be briefly discussed: a) Accuracy, precision, internal relative standard deviation (RISD) and external relative standard deviation (RESD) of isotope ratio measurements. With advanced instrumentation and use of standard reference materials, high accuracy and RESD = 0.002% (or better) may be achieved; b) The advantages of modern automatic isotope ratio mass spectrometer are briefly described. Computer controlled operation and data acquisition, and multiple ion collection are the recent important improvement; c) The isotopic fractionation during the course of isotope ratio measurement is considered as a major source of errors in thermal ionization of metallic elements. The phenomenon in strontium, neodymium, uranium, lead and calcium and methods to correct the measured data are discussed; d) Applications of isotope ratio mass spectrometry in atomic weight determinations, the isotope dilution technique, isotope geology, and isotope effects in biological systems are described together with specific applications in various research and technology area. (author)

  15. High-precision lead isotope ratio measurement by inductively coupled plasma multiple collector mass spectrometry

    International Nuclear Information System (INIS)

    Walder, A.J.; Furuta, Naoki.

    1993-01-01

    An inductively coupled plasma (ICP) ion source coupled to a magnetic sector mass analyser equipped with seven Faraday detectors has been used to measure the lead isotope ratios in solutions of Sanshiro Pond sediment collected at the University of Tokyo, airborne particulates collected at Shinjuku in Tokyo and Merck multielement standard product number 97279494. A thallium correction technique was utilized to allow a simultaneous correction for mass bias. This work followed an earlier interlaboratory comparison study of the above-mentioned solutions using ICP quadrupole mass spectrometry, and has demonstrated a considerable improvement in analytical precision. The following isotope ratio measurements were recorded. Pond sediment solution containing 82 ng ml -1 lead: 206 Pb/ 204 Pb=17.762±0.014; 206 Pb/ 207 Pb=1.1424±0.0009; 208 Pb/ 204 Pb=37.678±0.034. Airborne particulate solution containing 45 ng ml -1 lead: 206 Pb/ 204 Pb=17.969±0.006; 206 Pb/ 207 Pb=1.1528±0.0003; 208 Pb/ 204 Pb=37.915±0.021. Merck multielement standard solution containing 100 ng ml -1 lead: 206 Pb/ 204 Pb=19.255±0.015; 206 Pb/ 207 Pb=1.2238±0.0004; 208 Pb/ 204 Pb=38.476±0.021 (All errors are given as ±2 standard deviations). (author)

  16. Lead isotope in mineral exploration

    International Nuclear Information System (INIS)

    Gulson, B.L.

    1986-01-01

    This book provides an up-to-date state-of-the-art review of lead isotopes in mineral exploration. Beginning with an historical review on suggested uses of lead isotopes in mineral exploration, the author then outlines the theoretical aspects of lead isotopes and illustrates that the method is based on well-known principles of radioactive decay, from which isotopic signatures for different styles of mineralization are derived. The varying isotopic signatures are then introduced. The major part of the book details over 40 case histories for base and precious metals, uranium and tin using sampling media such as sulfides, gossans, soils, weathered bedrock, vegetation and groundwaters. Advantages and disadvantages of each are discussed. Examples are given of the use of lead isotopes in testing conceptual models for exploration. The success rate and cost-effectiveness of the method are illustrated by actual exploration examples. Analytical advances which should lower the cost of the method and future uses are outlined. Many of the case histories use recently published or unpublished data, 27 tables of which are given in an appendix. Details of sampling, the methods for obtaining the isotope ratios, and a commercially-available integrated lead isotope service are also provided. (Auth.)

  17. A on-line method for the determination of lead and lead isotope ratios in fresh and saline waters by inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Halicz, Ludwik; Lam, J.W.H.; McLaren, J.W.

    1994-01-01

    A previously reported on-line ICP-MS method for the determination of lead and other trace elements in seawater has been re-examined to determine its suitability for the determination of lead isotope ratios ( 206 Pb/ 207 Pb and 207 Pb/ 208 Pb) in fresh and saline natural waters. A detection limit of 0.9 ng/1 for total lead (for a 5 ml sample) was achieved. Precision of isotope ratio data was 0.2-0.3% RSD at a Pb concentration of 1 μg/l, and was still better than 2% at concentrations of only 10-40 ng/1 in seawater certified reference materials (CRMs). For all three natural water CRMs examined, measured precision was very close to the limit predicted by counting statistics. (Author)

  18. Lead isotope analyses of standard rock samples

    International Nuclear Information System (INIS)

    Koide, Yoshiyuki; Nakamura, Eizo

    1990-01-01

    New results on lead isotope compositions of standard rock samples and their analytical procedures are reported. Bromide form anion exchange chromatography technique was adopted for the chemical separation lead from rock samples. The lead contamination during whole analytical procedure was low enough to determine lead isotope composition of common natural rocks. Silica-gel activator method was applied for emission of lead ions in the mass spectrometer. Using the data reduction of 'unfractionated ratios', we obtained good reproducibility, precision and accuracy on lead isotope compositions of NBS SRM. Here we present new reliable lead isotope compositions of GSJ standard rock samples and USGS standard rock, BCR-1. (author)

  19. Application of laser ablation inductively coupled plasma multicollector mass spectometry in determination of lead isotope ratios in common glass for forensic purposes

    International Nuclear Information System (INIS)

    Sjåstad, Knut-Endre; Andersen, Tom; Simonsen, Siri Lene

    2013-01-01

    Samples of glass used as trace evidence in criminal cases are commonly small, with particle sizes below a millimeter. To perform chemical analysis suitable for forensic purposes, methods capable of analyzing such small samples are required. In this paper, analyses of lead isotope ratios by means of laser ablation inductively coupled multicollector mass spectrometry (LA-MC-ICP-MS) are presented. Sampling by use of laser ablation allows fragments down to 0.1 mg to be analyzed with sufficient precision to discriminate between glasses of different origin. In fact, the use of lead isotopes determined by LA-MC-ICP-MS approaches the discrimination attainable by multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) analysis of dissolved samples of 5 mg or more. Further, we have obtained a probability distribution by two dimensional kernel density estimates for the collected data set as an alternative presentation method to the well-established bivariate plot. The underlying information available from kernel density estimates is of importance for forensic scientists involved in probabilistic interpretation of physical evidence. - Highlights: • Lead isotope ratios prove suitable to discriminate glass for forensic purposes. • 96% of glass samples from different sources were separated by lead isotopic ratios. • Laser ablation allows fragments of glass with extension of 0.5 mm to be analyzed. • Isotopic ratios of lead are well suited for statistical analysis of evidence

  20. Identification of sources of lead exposure in French children by lead isotope analysis: a cross-sectional study

    Directory of Open Access Journals (Sweden)

    Lucas Jean-Paul

    2011-08-01

    Full Text Available Abstract Background The amount of lead in the environment has decreased significantly in recent years, and so did exposure. However, there is no known safe exposure level and, therefore, the exposure of children to lead, although low, remains a major public health issue. With the lower levels of exposure, it is becoming more difficult to identify lead sources and new approaches may be required for preventive action. This study assessed the usefulness of lead isotope ratios for identifying sources of lead using data from a nationwide sample of French children aged from six months to six years with blood lead levels ≥25 μg/L. Methods Blood samples were taken from 125 children, representing about 600,000 French children; environmental samples were taken from their homes and personal information was collected. Lead isotope ratios were determined using quadrupole ICP-MS (inductively coupled plasma - mass spectrometry and the isotopic signatures of potential sources of exposure were matched with those of blood in order to identify the most likely sources. Results In addition to the interpretation of lead concentrations, lead isotope ratios were potentially of use for 57% of children aged from six months to six years with blood lead level ≥ 25 μg/L (7% of overall children in France, about 332,000 children, with at least one potential source of lead and sufficiently well discriminated lead isotope ratios. Lead isotope ratios revealed a single suspected source of exposure for 32% of the subjects and were able to eliminate at least one unlikely source of exposure for 30% of the children. Conclusions In France, lead isotope ratios could provide valuable additional information in about a third of routine environmental investigations.

  1. Tracing the origin of pollution in French Alpine snow and aerosols using lead isotopic ratios.

    Science.gov (United States)

    Veysseyre, A M; Bollhöfer, A F; Rosman, K J; Ferrari, C P; Boutron, C F

    2001-11-15

    Fresh snow samples collected at 15 remote locations and aerosols collected at one location in the French Alps between November 1998 and April 1999 have been analyzed for Pb concentration and isotopic composition by thermal ionization mass spectrometry. The snow samples contained 19-1300 pg/g of Pb with isotopic ratios 206Pb/207Pb (208Pb/207Pb) of 1.1279-1.1607 (2.3983-2.4302). Airborne Pb concentrations at one sampling site ranged from 0.42 to 6.0 ng/m3 with isotopic ratios of 1.1321-1.1427 (2.4029-2.4160). Air mass trajectory analysis combined with isotopic compositions of potential source regions did not show discernible evidence of the long-range atmospheric transport of pollutants. Isotopic ratios in the Alpine snow samples and thus the free troposphere were generally higher than airborne Pb isotopic ratios in urban France, which coupled with the relatively high Pb concentrations suggested a regional anthropogenic Pb source, probably Italy but possibly Eastern Europe.

  2. Characteristics of trace elements and lead isotope ratios in PM2.5 from four sites in Shanghai

    International Nuclear Information System (INIS)

    Chen Jianmin; Tan Mingguang; Li Yulan; Zheng Jian; Zhang Yuanmao; Shan Zuci; Zhang Guilin; Li Yan

    2008-01-01

    PM 2.5 samples were collected in Shanghai at four sites with different typical land-uses. The sampling was done concurrently once per month from April 2004 to April 2005, and the ambient mass concentration, the elemental composition and the stable lead isotope ratios in these PM 2.5 samples were determined. The annual average concentrations of PM 2.5 samples at each site were 84 ± 30, 65 ± 20, 55 ± 18, and 41 ± 10 μg m -3 , respectively, indicating there were severe air pollution levels in Shanghai. The enrichment factor was calculated for each element and the comparison and discussion of elements with significant anthropogenic contributions between Shanghai and Tokyo suggested that the major source of PM 2.5 in Shanghai was not traffic-derived emissions, but the stationary industrial contribution emitted from coal use. Moreover, the analysis of stable lead isotope ratios revealed only a slight difference within the samples at the four sites which fell well within the scope of coal composition difference, further confirming that the contribution from stationary industrial emissions to atmospheric lead pollution of PM 2.5 was very substantial in Shanghai

  3. Australian atmospheric lead deposition reconstructed using lead concentrations and isotopic compositions of archival lichen and fungi

    International Nuclear Information System (INIS)

    Wu, Liqin; Taylor, Mark Patrick; Handley, Heather K.; Wu, Michael

    2016-01-01

    Lead concentrations and their isotopic compositions were measured in lichen genera Cladonia and Usnea and fungi genus Trametes from the Greater Sydney region (New South Wales, Australia) that had been collected and archived over the past 120 years. The median lead concentrations were elevated in lichens and fungi prior to the introduction of leaded petrol (Cladonia 12.5 mg/kg; Usnea 15.6 mg/kg; Trametes 1.85 mg/kg) corresponding to early industrial development. During the period of leaded petrol use in Australian automobiles from 1932 to 2002, total median lead concentrations rose: Cladonia 18.8 mg/kg; Usnea 21.5 mg/kg; Trametes 4.3 mg/kg. Following the cessation of leaded petrol use, median total lead concentrations decreased sharply in the 2000s: Cladonia 4.8 mg/kg; Usnea 1.7 mg/kg. The lichen and fungi isotopic compositions reveal a significant decrease in "2"0"6Pb/"2"0"7Pb ratios from the end of 19th century to the 1970s. The following decades were characterised by lower allowable levels of lead additive in fuel and the introduction of unleaded petrol in 1985. The environmental response to these regulatory changes was that lichen and fungi "2"0"6Pb/"2"0"7Pb ratios increased, particularly from 1995 onwards. Although the lead isotope ratios of lichens continued to increase in the 2000s they do not return to pre-leaded petrol values. This demonstrates that historic leaded petrol emissions, inter alia other sources, remain a persistent source of anthropogenic contamination in the Greater Sydney region. - Highlights: • Total lead and isotopic composition can be measured in historic lichen and fungi. • Historic lichen and fungi samples can distinguish polluted and unpolluted areas. • Former leaded petrol depositions remain a significant environmental contaminant. - Analysis of a 120-year record of lichens and fungi from the Greater Sydney basin reveal marked shifts in total lead concentrations and lead isotope ratios in response to geogenic inputs

  4. Determination of uranium, thorium and radium isotope ratio

    International Nuclear Information System (INIS)

    Sokolova, Z.A.

    1983-01-01

    The problems connected with the study of isotope composition of natural radioactive elements in natural objects are considered. It is pointed out that for minerals, ores and rocks the following ratios are usually determined: 234 U/ 238 U, 230 Th/ 238 U, 226 Ra/ 238 U, 228 Th/ 230 Th, 228 Th/ 232 Th and lead isotopes; for natural waters, besides the enumerated - 226 Ra/ 228 Ra. General content of uranium and thorium in the course of isotope investigations is determined from separate samples, most frequently by the X-ray spectral method, radium content - by usual radiochemical method, uranium and radium content in waters -respectively by calorimetric and emanation methods. Radiochemical preparation of geologic powder and aqueous samples for isotope analysis is described in detail. The technique of measuring and calculating isotope ratios (α-spectrometry for determining isotope composition of uranium and thorium and emanation method for determining 226 Ra/ 228 Ra) is presented

  5. Isotope analytics for the evaluation of the feeding influence on the isotope ratio in beef samples

    International Nuclear Information System (INIS)

    Herwig, Nadine

    2010-01-01

    Information about the origin of food and associated production systems has a high significance for food control. An extremely promising approach to obtain such information is the determination of isotope ratios of different elements. In this study the correlation of the isotope ratios C-13/C-12, N-15/N-14, Mg-25/Mg-24, and Sr-87/Sr-86 in bovine samples (milk and urine) and the corresponding isotope ratios in feed was investigated. It was shown that in the bovine samples all four isotope ratios correlate with the isotope composition of the feed. The isotope ratios of strontium and magnesium have the advantage that they directly reflect the isotope ratios of the ingested feed since there is no isotope fractionation in the bovine organism which is in contrast to the case of carbon and nitrogen isotope ratios. From the present feeding study it is evident, that a feed change leads to a significant change in the delta C-13 values in milk and urine within 10 days already. For the deltaN-15 values the feed change was only visible in the bovine urine after 49 days. Investigations of cows from two different regions (Berlin/Germany and Goestling/Austria) kept at different feeding regimes revealed no differences in the N-15/N-14 and Mg-26/Mg-24 isotope ratios. The strongest correlation between the isotope ratio of the bovine samples and the kind of ingested feed was observed for the carbon isotope ratio. With this ratio even smallest differences in the feed composition were traceable in the bovine samples. Since different regions usually coincide with different feeding regimes, carbon isotope ratios can be used to distinguish bovine samples from different regions if the delta C-13 values of the ingested feed are different. Furthermore, the determination of strontium isotope ratios revealed significant differences between bovine and feed samples of Berlin and Goestling due to the different geologic realities. Hence the carbon and strontium isotope ratios allow the best

  6. Three-stage method for interpretation of uranium-lead isotopic data

    International Nuclear Information System (INIS)

    Nejmark, L.A.; Ovchinnikova, G.V.; Levchenkov, O.A.

    1982-01-01

    Three-dimensional approach for the iterpretation of uranium-lead isoto e ratios in pnatural systems, development of which corresponds to three stages, has been considered. In the framework of the three-stage model two cases, differing in the character of uranium-lead systems violation at the beginning of the third stage, are discussed. The first case corresponds to uranium addition or lead substraction, and the second one - to addition of lead of unknown isotopic content. Three-stage approach permits without amending the isotopic content of lead captured during crystallization to calculated the beginning of the second and third stages of uranium-lead systems development and to evaluate parameters of lead added to the system. Concrete examples of interpretation of uranium-lead isotopic ratios in minerals and rock samples as a whole both of the terrestrial and cosmic origin are considered. Possibilities and limitations of the three-stage approach are analyzed and directions of further development are outlined

  7. Biogeochemical studies of lead isotopes near a smelter

    International Nuclear Information System (INIS)

    Landrigan, P.J.; Baker, E.L. Jr.; Earl, J.L.; Chow, T.J.

    1975-01-01

    Ninety-nine percent of 1 to 9 year-old children living within 1 mile of a primary lead smelter in Idaho were found to have whole blood lead levels equal to or greater than 40μg/100 ml, a level indicative of excess lead absorption. To define the sources of this lead, isotope ratios were determined in lead from human and environmental samples obtained near the smelter; determinations were performed using a 30-cm radius, solid-source mass spectrometer with an electron multiplier. The Idaho ore is a pre-Cambrian lead deposit with 206 Pb/ 204 Pb = 16.43, 206 Pb = 1.0543 and 206 Pb/ 208 Pb = 0.4518. An ingot smelted in 1974 showed isotope ratios of 206 Pb/ 204 Pb = 17.66, 206 Pb/ 207 Pb = 1.1312 and 206 Pb/ 208 Pb = 0.4694, indicating a mixture of ore sources. Three surface soil samples from within 2 miles of the smelter had lead ratios similar to those in the ingot. A fourth soil sample from beside an interstate highway 32 miles east of the smelter showed different ratios: 206 Pb/ 204 Pb = 18.47, 206 Pb/ 207 Pb = 1.1826 and 206 Pb/ 208 Pb = 0.4823. Aerosol samples collected from October 4, 1974, to February 1, 1975, near the smelter showed considerable variation in ratios; these variations resulted from smelting of ores from differing sources

  8. Investigation of the anomalous isotope ratios of the Central-Transdanubian bauxites

    International Nuclear Information System (INIS)

    Viczian, M.

    1977-01-01

    In the case of the Central Transdanubian bauxite deposits significant anomaly of the lead isotope ratios has been found. The 206 Pb/ 204 Pb isotope ratio in approximately 40 samples was investigated and the results have shown an average deviation from the literary value by about 80%. These results have been cont confirmed by thermal ionisation measurings, too. Some possibilities for the explanation of this isotope anomaly are also dealt with in the paper. (author)

  9. Lead exposure in raptors from Japan and source identification using Pb stable isotope ratios.

    Science.gov (United States)

    Ishii, Chihiro; Nakayama, Shouta M M; Ikenaka, Yoshinori; Nakata, Hokuto; Saito, Keisuke; Watanabe, Yukiko; Mizukawa, Hazuki; Tanabe, Shinsuke; Nomiyama, Kei; Hayashi, Terutake; Ishizuka, Mayumi

    2017-11-01

    Lead (Pb) poisoning is widespread among raptors and water birds. In Japan, fragments of Pb ammunition are still found in endangered eagles although more than 10 years have passed since legislation regarding use of Pb ammunition was introduced. This study was performed to investigate Pb exposure in raptors from various locations in Japan. We measured hepatic and renal Pb concentrations and hepatic Pb isotope ratios of Steller's sea eagles (Haliaeetus pelagicus), white-tailed sea eagles (Haliaeetus albicilla), golden eagles (Aquila chrysaetos), and 13 other species (total 177 individuals) that were found dead, as well as blood samples from three eagles found in a weakened state during 1993-2015 from Hokkaido (northern part), Honshu (the main island), and Shikoku (a southern island) of Japan. In the present study in Hokkaido, one quarter of the sea eagles showed a high Pb concentration, suggesting exposure to abnormally high Pb levels and Pb poisoning. Pb isotope ratios indicated that endangered Steller's sea eagle and white-tailed sea eagle were poisoned by Pb ammunition that was used illegally in Hokkaido. In other areas of Japan, both surveillance and regulations were less extensive than in Hokkaido, but Pb poisoning in raptors was also noted. Therefore, Pb poisoning is still a serious problem in raptors in various areas of Japan due to accidental ingestion of materials containing Pb, especially Pb ammunition. Copyright © 2017. Published by Elsevier Ltd.

  10. Lead isotopes as seepage indicators around a uranium tailings dam

    International Nuclear Information System (INIS)

    Gulson, B.L.; Mizon, K.J.; Korsch, M.J.; Noller, B.N.

    1989-01-01

    Lead isotope ratios and lead concentrations have been measured in water from 26 bores around the Ranger uranium tailings dam, Northern Territory, Australia, and from the dam itself to determine possible migration of lead derived from the radioactive decay of uranium. Lead isotope compositions have also been measured for the particulates retained on selected filters. The concentration of lead in the bore waters is extremely low (usually 206 Pb/ 204 Pb ratio measured in the bore waters differs by more than a factor of 100 from that in the tailings dam and shows no evidence of lead derived from a significant uranium accumulation. It may be possible to distinguish between lead from the tailings dam and that derived from a nearby uranium ore body

  11. Detecting isotopic ratio outliers

    Science.gov (United States)

    Bayne, C. K.; Smith, D. H.

    An alternative method is proposed for improving isotopic ratio estimates. This method mathematically models pulse-count data and uses iterative reweighted Poisson regression to estimate model parameters to calculate the isotopic ratios. This computer-oriented approach provides theoretically better methods than conventional techniques to establish error limits and to identify outliers.

  12. Detecting isotopic ratio outliers

    International Nuclear Information System (INIS)

    Bayne, C.K.; Smith, D.H.

    1986-01-01

    An alternative method is proposed for improving isotopic ratio estimates. This method mathematically models pulse-count data and uses iterative reweighted Poisson regression to estimate model parameters to calculate the isotopic ratios. This computer-oriented approach provides theoretically better methods than conventional techniques to establish error limits and to identify outliers

  13. Detecting isotopic ratio outliers

    International Nuclear Information System (INIS)

    Bayne, C.K.; Smith, D.H.

    1985-01-01

    An alternative method is proposed for improving isotopic ratio estimates. This method mathematically models pulse-count data and uses iterative reweighted Poisson regression to estimate model parameters to calculate the isotopic ratios. This computer-oriented approach provides theoretically better methods than conventional techniques to establish error limits and to identify outliers. 6 refs., 3 figs., 3 tabs

  14. Lead Isotope Characterization of Petroleum Fuels in Taipei, Taiwan

    Directory of Open Access Journals (Sweden)

    Pei-Hsuan Yao

    2015-04-01

    Full Text Available Leaded gasoline in Taiwan was gradually phased out from 1983 to 2000. However, it is unclear whether unleaded gasoline still contributes to atmospheric lead (Pb exposure in urban areas. In this study, Pb isotopic compositions of unleaded gasolines, with octane numbers of 92, 95, 98, and diesel from two local suppliers in Taipei were determined by multi-collector inductively coupled plasma mass spectrometry with a two-sigma uncertainty of ± 0.02 %. Lead isotopic ratios of vehicle exhaust (208Pb/207Pb: 2.427, 206Pb/207Pb: 1.148, as estimated from petroleum fuels overlap with the reported aerosol data. This agreement indicates that local unleaded petroleum fuels, containing 10–45 ng·Pb·g−1, are merely one contributor among various sources to urban aerosol Pb. Additionally, the distinction between the products of the two companies is statistically significant in their individual 208Pb/206Pb ratios (p-value < 0.001, t test. Lead isotopic characterization appears to be applicable as a “fingerprinting” tool for tracing the sources of Pb pollution.

  15. Lead isotope measurements on aerosol samples with ICP-MS

    International Nuclear Information System (INIS)

    Widmer, C.R.; Kraehenbuehl, U.; Kramers, J.; Tobler, L.

    2000-01-01

    Size fractionated aerosols were collected with low pressure Berner impactors on a radio/TV tower 110 m above ground on a hill 10 km east of Bern at a total elevation of 1060 m asl. Two different wind sectors were chosen with the goal of assessing any differences in lead concentration and the 3 radiogenic lead isotopes (206,207,208) for east and west wind, respectively. A leaching technique was used to extract the lead quantitatively from the surface of the impaction foils. This method has been proven to be better suited for airborne particles than complete microwave digestion because it is less time consuming and contamination risk is smaller. Blank considerations played a major role in choosing all the chemicals, tubes, beakers and selecting the analytical method. Lead concentrations were determined with GF-AAS and lead isotopes with two different ICP-MS systems, one being a multicollector system. Precision of the simultaneous multicollector system was found to be at least a factor of 3 better than that of the sequentially operating ICP-MS. The small variations in isotope ratios from the two wind sectors can be distinctly seen with this enhanced precision. The observed relative difference in isotope ratios between east- and westwind was ∝0.6% for 207 Pb/ 206 Pb and ∝0.5% for 208 Pb/ 206 Pb. (orig.)

  16. Stable lead isotopes and lake sediments. A useful combination for the study of atmospheric lead pollution history

    Energy Technology Data Exchange (ETDEWEB)

    Renberg, I.; Braennvall, M.-L.; Bindler, R. [Department of Ecology and Environmental Science, Umea University, SE-901 87 Umea (Sweden); Emteryd, O. [Department of Forest Ecology, Swedish University of Agricultural Sciences, SE-901 83 Umea (Sweden)

    2002-06-20

    Analysis of stable lead isotopes and lead concentrations in lake-sediment deposits, not least in varved (annually-laminated) sediments, is a useful method to study lead pollution history. This paper presents details from a study of 31 lakes in Sweden. Using a strong acid digestion of sediment samples and ICP-MS analyses, we have found that Swedish lake sediments have a high natural (pre-pollution) 206[Pb]/207[Pb] ratio (mean 1.52{+-}0.18, range 1.28-2.01, n=31 lakes). In contrast, atmospheric lead pollution derived from metal smelting processes, coal burning and from alkyl-lead added to petrol has a lower ratio (<1.2). Consequently, when pollution lead deposition began approximately 3500 years ago, the lead isotope ratio of the sediments started to decline, and in modern sediments it is typically <1.2. Using the isotope and concentration values and a mixing model, the relative contribution of pollution and natural lead in sediment samples can be calculated. The pollution lead records of the Swedish lake sediments show a consistent picture of the atmospheric lead pollution history. Some noticeable features are the Roman peak, the large and permanent Medieval increase, peaks at approximately 1200 and 1530 ad, the rapid increase after World War II, the peak in the 1970s, and the large modern decline.

  17. Lead isotopes and lead shot ingestion in the globally threatened marbled teal (Marmaronetta angustirostris) and white-headed duck (Oxyura leucocephala)

    International Nuclear Information System (INIS)

    Svanberg, Fredrik; Mateo, Rafael; Hillstroem, Lars; Green, Andy J.; Taggart, Mark A.; Raab, Andrea; Meharg, Andy A.

    2006-01-01

    Lead isotope ratios ( 206 Pb/ 207 Pb and 208 Pb/ 207 Pb) and concentrations in the livers and bones of marbled teal and white-headed duck found dead or moribund were determined in order to establish the main lead source in these waterfowl species. Lead concentrations in bone (dry weight) and liver (wet weight) were found to be very high in many of the white-headed ducks (bone: geometric mean = 88.9 ppm, maximum = 419 ppm; liver: geometric mean = 16.8 ppm, maximum = 57.0 ppm). Some of the marbled teal had high lead levels in the bones but liver lead levels were all low (bone: geometric mean = 6.13 ppm, maximum = 112 ppm; liver: geometric mean = 0.581 ppm, maximum = 4.77 ppm). Ingested lead shot were found in 71% of the white-headed duck and 20% of the marbled teal. The 206 Pb/ 207 Pb ratio in livers and bones of white-headed ducks and marbled teals showed no significant differences compared to the ratios obtained from lead shot. The 206 Pb/ 207 Pb ratio in bones of marbled teal ducklings with the highest lead concentrations tended to resemble the ratios of lead shot, which supports our hypothesis that the lead was derived from the hens. We also found that the lead ratios of lead shot and lead ratios described for soils in the area overlapped, but also that the isotopic ratio 206 Pb/ 207 Pb in lead shot used in Spain has a narrow range compared with those used in North America. The principal source of lead in many of these birds was, however, most likely lead shot, as supported by the similar isotopic ratios, high lead concentrations in tissues and evidence of ingested shot

  18. Lead isotopes and lead shot ingestion in the globally threatened marbled teal (Marmaronetta angustirostris) and white-headed duck (Oxyura leucocephala)

    Energy Technology Data Exchange (ETDEWEB)

    Svanberg, Fredrik [Department of Environmental Toxicology, Evolutionary Biology Centre, Uppsala University, Norbyvaegen 18A, SE-752 36 Uppsala (Sweden)]. E-mail: fredriksvanberg@hotmail.com; Mateo, Rafael [Instituto de Investigacion en Recursos Cinegeticos, IREC (CSIC-UCLM-JCCM), Ronda de Toledo s/n, 13071 Ciudad Real (Spain); Hillstroem, Lars [Institute of Maths, Natural and Computer Science, University of Gaevle, SE-801 76 Gaevle (Sweden); Green, Andy J. [Wetland Ecology Group, Estacion Biologica de Donana-CSIC, Pabellon del Peru, Avenida Maria Luisa s/n, E-40013 Seville (Spain); Taggart, Mark A. [School of Biological Sciences, University of Aberdeen, Cruickshank Bld, St Machar Dr, Aberdeen, Scotland, AB24 3UU (United Kingdom); Raab, Andrea [School of Biological Sciences, University of Aberdeen, Cruickshank Bld, St Machar Dr, Aberdeen, Scotland, AB24 3UU (United Kingdom); Meharg, Andy A. [School of Biological Sciences, University of Aberdeen, Cruickshank Bld, St Machar Dr, Aberdeen, Scotland, AB24 3UU (United Kingdom)

    2006-11-01

    Lead isotope ratios ({sup 206}Pb/{sup 207}Pb and {sup 208}Pb/{sup 207}Pb) and concentrations in the livers and bones of marbled teal and white-headed duck found dead or moribund were determined in order to establish the main lead source in these waterfowl species. Lead concentrations in bone (dry weight) and liver (wet weight) were found to be very high in many of the white-headed ducks (bone: geometric mean = 88.9 ppm, maximum = 419 ppm; liver: geometric mean = 16.8 ppm, maximum = 57.0 ppm). Some of the marbled teal had high lead levels in the bones but liver lead levels were all low (bone: geometric mean = 6.13 ppm, maximum = 112 ppm; liver: geometric mean = 0.581 ppm, maximum = 4.77 ppm). Ingested lead shot were found in 71% of the white-headed duck and 20% of the marbled teal. The {sup 206}Pb/{sup 207}Pb ratio in livers and bones of white-headed ducks and marbled teals showed no significant differences compared to the ratios obtained from lead shot. The {sup 206}Pb/{sup 207}Pb ratio in bones of marbled teal ducklings with the highest lead concentrations tended to resemble the ratios of lead shot, which supports our hypothesis that the lead was derived from the hens. We also found that the lead ratios of lead shot and lead ratios described for soils in the area overlapped, but also that the isotopic ratio {sup 206}Pb/{sup 207}Pb in lead shot used in Spain has a narrow range compared with those used in North America. The principal source of lead in many of these birds was, however, most likely lead shot, as supported by the similar isotopic ratios, high lead concentrations in tissues and evidence of ingested shot.

  19. Lead isotopic studies of the Samail ophiolite, Oman

    Energy Technology Data Exchange (ETDEWEB)

    Chen, J.H.; Pallister, J.S.

    1981-04-10

    The isotopic composition of Pb and the concentrations of U, Th, and Pb have been determined for samples from various lithologic units and massive sulfides of the Samail ophiolite. The observed /sup 206/Pb//sup 204/Pb ratios range from 17.90 to 19.06, /sup 207/Pb//sup 204/Pb ratios from 15.43 to 15.63, and /sup 208/Pb//sup 204/Pb from 37.66 to 38.78. In Pb isotopic evolution diagrams, the initial Pb isotopic compositions of most of the samples from the Samail ophiolite plot within the field of oceanic basalt, clearly distinct from island arc data, and define some of the least radiogenic Pb observed from oceanic rocks. Lead data from the Samail are compatible with a model involving magma generation from an oceanic mantle source and formation of the ophiolite at an oceanic spreading center. U--Th--Pb isotopic systematics demonstrate that vertical heterogeneity in the oceanic crust can be created through differential concentration of U, Th, and Pb during crystal fractionation and alteration at, or near, the spreading ridge. Calcite form amygdules in the ophiolite basalt has similar Pb isotopic composition to the igneous rocks, suggesting precipitation of the calcite from seawater which contained Pb derived mostly from the oceanic crust. Lead isotopic data on Fe--Cu sulfides are also similar to the results from the igneous suite suggesting that the source of the sulfides is predominently from the oceanic crust. Lead data from serpentinized peridotite and a galena sample from below the ophiolite suggest that part of the serpentinization process and the formation of galena could involve addition of radiogenic Pb from either a continental source or from oceanic sediments.

  20. Isotopic ratios in the solar system

    International Nuclear Information System (INIS)

    1985-01-01

    This colloquium is aimed at presentation of isotope ratio measurements in different objects of solar system and surrounding interstellar space and evaluation of what information on composition and structure of primitive solar nebula and on chemical evolution of interstellar space in this part of the galaxy can be deduced from it. Isotope ratio in solar system got from laboratory study of extraterrestrial materials is a subject of this colloquium. Then isotope ratio measured in solar wind, planets and comets. Measurements either are made in-situ by mass spectrometry of ions in solar wind or planetery atmosphere gases either are remote measurements of spectra emitted by giant planets and comets. At last, planetology and astrophysics implications are presented and reviewed. Consraints for solar system formation model can be deduced from isotope ratio measurement. Particularly, isotope anomalies are marks of the processes, which have influenced the primitive solar nebula contraction [fr

  1. Lead (Pb) Isotope Baselines for Studies of Ancient Human Migration and Trade in the Maya Region

    Science.gov (United States)

    Kamenov, George D.; Gilli, Adrian; Hodell, David A.; Emery, Kitty F.; Brenner, Mark; Krigbaum, John

    2016-01-01

    We examined the potential use of lead (Pb) isotopes to source archaeological materials from the Maya region of Mesoamerica. The main objectives were to determine if: 1) geologic terrains throughout the Maya area exhibit distinct lead isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb), and 2) a combination of lead and strontium ratios can enhance sourcing procedures in the Mesoamerica region. We analyzed 60 rock samples for lead isotope ratios and a representative subset of samples for lead, uranium, and thorium concentrations across the Maya region, including the Northern Lowlands of the Mexican Yucatan Peninsula, the Southern Lowlands of Guatemala and Belize, the Volcanic Highlands, the Belizean Maya Mountains, and the Metamorphic Province/Motagua Valley. Although there is some overlap within certain sub-regions, particularly the geologically diverse Metamorphic Province, lead isotopes can be used to distinguish between the Northern Lowlands, the Southern Lowlands, and the Volcanic Highlands. The distinct lead isotope ratios in the sub-regions are related to the geology of the Maya area, exhibiting a general trend in the lowlands of geologically younger rocks in the north to older rocks in the south, and Cenozoic volcanic rocks in the southern highlands. Combined with other sourcing techniques such as strontium (87Sr/86Sr) and oxygen (δ18O), a regional baseline for lead isotope ratios can contribute to the development of lead isoscapes in the Maya area, and may help to distinguish among geographic sub-regions at a finer scale than has been previously possible. These isotope baselines will provide archaeologists with an additional tool to track the origin and movement of ancient humans and artifacts across this important region. PMID:27806065

  2. Lead (Pb) Isotope Baselines for Studies of Ancient Human Migration and Trade in the Maya Region.

    Science.gov (United States)

    Sharpe, Ashley E; Kamenov, George D; Gilli, Adrian; Hodell, David A; Emery, Kitty F; Brenner, Mark; Krigbaum, John

    2016-01-01

    We examined the potential use of lead (Pb) isotopes to source archaeological materials from the Maya region of Mesoamerica. The main objectives were to determine if: 1) geologic terrains throughout the Maya area exhibit distinct lead isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb), and 2) a combination of lead and strontium ratios can enhance sourcing procedures in the Mesoamerica region. We analyzed 60 rock samples for lead isotope ratios and a representative subset of samples for lead, uranium, and thorium concentrations across the Maya region, including the Northern Lowlands of the Mexican Yucatan Peninsula, the Southern Lowlands of Guatemala and Belize, the Volcanic Highlands, the Belizean Maya Mountains, and the Metamorphic Province/Motagua Valley. Although there is some overlap within certain sub-regions, particularly the geologically diverse Metamorphic Province, lead isotopes can be used to distinguish between the Northern Lowlands, the Southern Lowlands, and the Volcanic Highlands. The distinct lead isotope ratios in the sub-regions are related to the geology of the Maya area, exhibiting a general trend in the lowlands of geologically younger rocks in the north to older rocks in the south, and Cenozoic volcanic rocks in the southern highlands. Combined with other sourcing techniques such as strontium (87Sr/86Sr) and oxygen (δ18O), a regional baseline for lead isotope ratios can contribute to the development of lead isoscapes in the Maya area, and may help to distinguish among geographic sub-regions at a finer scale than has been previously possible. These isotope baselines will provide archaeologists with an additional tool to track the origin and movement of ancient humans and artifacts across this important region.

  3. Lead isotopes and trace metal ratios of aerosols as tracers of Pb pollution sources in Kanpur, India

    Science.gov (United States)

    Sen, Indra; Bizimis, Michael; Tripathi, Sachchida; Paul, Debajyoti; Tyagi, Swati; Sengupta, Deep

    2015-04-01

    The anthropogenic flux of Pb in the Earth's surface is almost an order of magnitude higher than its corresponding natural flux [1]. Identifying the sources and pathways of anthropogenic Pb in environment is important because Pb toxicity is known to have adverse effects on human health. Pb pollution sources for America, Europe, and China are well documented. However, sources of atmospheric Pb are unknown in India, particularly after leaded gasoline was phased out in 2000. India has a developing economy with a rapidly emerging automobile and high temperature industry, and anthropogenic Pb emission is expected to rise in the next decade. In this study, we report on the Pb- isotope compositions and trace metal ratios of airborne particulates collected in Kanpur, an industrial city in northern India. The Pb concentration in the airborne particulate matter varies between 14-216 ng/m3, while the other heavy metals vary by factor of 10 or less, e.g. Cd=0.3-3 ng/m3, As=0.4-3.5 ng/m3, Zn=36-161 ng/m3, and Cu=3-22 ng/m3. The 206Pb/207Pb, 208Pb/206Pb, and 208Pb/207Pb vary between 1.112 - 1.129, 2.123-2.141, and 2.409-2.424 respectively, and are highly correlated with each other (R2>0.9). Pb isotopes and trace metal data reveals that coal combustion is the major source of anthropogenic Pb in the atmosphere, with limited contribution from mining and smelting processes. We further conclude that combination of Pb isotope ratios and V/Pb ratios are powerful tracers for Pb source apportionment studies, which is otherwise difficult to differentiate based only on Pb systematics [1] Sen and Peucker-Ehrenbrink (2012), Environ. Sci. Technol.(46), 8601-8609

  4. Raman scattering method and apparatus for measuring isotope ratios and isotopic abundances

    International Nuclear Information System (INIS)

    Harney, R.C.; Bloom, S.D.

    1978-01-01

    Raman scattering is used to measure isotope ratios and/or isotopic abundances. A beam of quasi-monochromatic photons is directed onto the sample to be analyzed, and the resulting Raman-scattered photons are detected and counted for each isotopic species of interest. These photon counts are treated mathematically to yield the desired isotope ratios or isotopic abundances

  5. The use of lead isotope analysis to identify potential sources of lead toxicosis in a juvenile bald eagle (Haliaeetus leucocephalus) with ventricular foreign bodies

    Science.gov (United States)

    Franzen-Klein, Dana; McRuer, David; Slabe, Vincent; Katzner, Todd

    2018-01-01

    A male juvenile bald eagle (Haliaeetus leucocephalus) was admitted to the Wildlife Center of Virginia with a left humeral fracture a large quantity of anthropogenic debris in the ventriculus, a blood lead level of 0.616 ppm, and clinical signs consistent with chronic lead toxicosis. Because of the poor prognosis for recovery and release, the eagle was euthanatized. Lead isotope analysis was performed to identify potential anthropogenic sources of lead in this bird. The lead isotope ratios in the eagle's femur (0.8773), liver (0.8761), and kidneys (0.8686) were most closely related to lead paint (0.8925), leaded gasoline (0.8450), and zinc smelting (0.8240). The lead isotope ratios were dissimilar to lead ammunition (0.8179) and the anthropogenic debris in the ventriculus. This case report documents foreign body ingestion in a free-ranging bald eagle and demonstrates the clinical utility of lead isotope analysis to potentially identify or exclude anthropogenic sources of lead poisoning in wildlife patients.

  6. Determination of lead isotopic composition of airborne particulate matter by ICPMS: implications for lead atmospheric emissions in Canada

    International Nuclear Information System (INIS)

    Celo, V.; Dabek-Zlotorzynska, E.

    2009-01-01

    Full text: Quadrupole ICPMS was used for determination of trace metal concentrations and lead isotopic composition in fine particulate matter (PM 2.5 ) collected at selected sites within the Canadian National Air Pollution Surveillance network, from February 2005 to February 2007. High enrichment factors indicated that lead is mostly of anthropogenic origin and consequently, the lead isotopic composition is directly related to that of pollution sources. The 206 Pb/ 207 Pb and 208 Pb/ 207 Pb ratios were measured and the results were compared to the isotopic signatures of lead from different sources. Various approaches were used to assess the impact of relevant sources and the meteorological conditions in the occurrence and distribution of lead in Canadian atmospheric aerosols. (author)

  7. Radiogenic Lead Isotopes and Time Stratigraphy in the Hudson River, New York

    International Nuclear Information System (INIS)

    Chillrud, Steven N.; Bopp, Richard F.; Ross, James M.; Chaky, Damon A.; Hemming, Sidney; Shuster, Edward L.; Simpson, H. James; Estabrooks, Frank

    2004-01-01

    Radionuclide, radiogenic lead isotope and trace metal analyses on fine-grained sediment cores collected along 160 km of the upper and tidal Hudson River were used to examine temporal trends of contaminant loadings and to develop radiogenic lead isotopes both as a stratigraphic tool and as tracers for resolving decadal particle transport fluxes. Very large inputs of Cd, Sb, Pb, and Cr are evident in the sediment record, potentially from a single manufacturing facility. The total range in radiogenic lead isotope ratios observed in well-dated cores collected about 24 km downstream of the plant is large (e.g., maximum difference in 206 Pb/ 207 Pb is 10%), characterized by four major shifts occurring in the 1950s, 1960s, 1970s and 1980s. The upper Hudson signals in Cd and radiogenic lead isotopes were still evident in sediments collected 160 km downstream in the tidal Hudson. The large magnitude and abrupt shifts in radiogenic lead isotope ratios as a function of depth provide sensitive temporal constraints that complement information derived from radionuclide analyses to significantly improve the precision of dating assignments. Application of a simple dilution model to data from paired cores suggests much larger sediment inputs in one section of the river than previously reported, suggesting particle influxes to the Hudson have been underestimated

  8. Lead isotope ratios in six lake sediment cores from Japan Archipelago: Historical record of trans-boundary pollution sources

    International Nuclear Information System (INIS)

    Hosono, Takahiro; Alvarez, Kelly; Kuwae, Michinobu

    2016-01-01

    Sediment cores from six lakes situated from north to south on the Japanese Archipelago were collected during 2009–2010 to investigate the hypothesis that deposition of lead (Pb) was coming from East Asia (including China, South Korea and eastern part of Russia). Accumulation rates and ages of the lake sediment were estimated by the "2"1"0Pb constant rate of supply model and "1"3"7Cs inputs to reconstruct the historical trends of Pb accumulation. Cores from four lakes located in the north and central Japan, showed clear evidence of Pb pollution with a change in the "2"0"6Pb/"2"0"7Pb and "2"0"8Pb/"2"0"7Pb ratios in the recent sediment as compared to the deeper sediment. Among the six studied lakes, significant inputs of anthropogenic lead emissions were observed at Lake Mikazuki (north Hokkaido in north Japan), Lake Chokai (north of Honshu), and Lake Mikuriga (central part of Honshu). Pb isotopic comparison of collected core sediment and previously reported data for wet precipitation and aerosols from different Asian regions indicate that, before 1900, Pb accumulated in these three lakes was not affected by trans-boundary sources. Lake Mikazuki started to receive Pb emissions from Russia in early 1900s, and during the last two decades, this lake has been affected by trans-boundary Pb pollution from northern China. Lake Chokai has received Pb pollutant from northern China since early 1900s until 2009, whereas for the Lake Mikuriga the major Pb contaminant was transported from southern China during the past 100 years. The results of our study demonstrate that Japan Archipelago has received trans-boundary Pb emissions from different parts of East Asian region depending on location, and the major source region has changed historically. - Highlights: • Historical trend of Pb pollution was recorded in six Japanese Lakes. • Pb concentration and Pb isotope ratios were determined for sediment cores. • High [Pb] and less radiogenic Pb isotope ratios were observed since

  9. Lead isotope ratios in six lake sediment cores from Japan Archipelago: Historical record of trans-boundary pollution sources

    Energy Technology Data Exchange (ETDEWEB)

    Hosono, Takahiro, E-mail: hosono@kumamoto-u.ac.jp [Priority Organization for Innovation and Excellence, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Alvarez, Kelly [Priority Organization for Innovation and Excellence, Kumamoto University, 2-39-1 Kurokami, Kumamoto 860-8555 (Japan); Kuwae, Michinobu [Senior Research Fellow Center, Ehime University, 2-5 Bunkyo-cho, Matsuyama 790-8577 (Japan)

    2016-07-15

    Sediment cores from six lakes situated from north to south on the Japanese Archipelago were collected during 2009–2010 to investigate the hypothesis that deposition of lead (Pb) was coming from East Asia (including China, South Korea and eastern part of Russia). Accumulation rates and ages of the lake sediment were estimated by the {sup 210}Pb constant rate of supply model and {sup 137}Cs inputs to reconstruct the historical trends of Pb accumulation. Cores from four lakes located in the north and central Japan, showed clear evidence of Pb pollution with a change in the {sup 206}Pb/{sup 207}Pb and {sup 208}Pb/{sup 207}Pb ratios in the recent sediment as compared to the deeper sediment. Among the six studied lakes, significant inputs of anthropogenic lead emissions were observed at Lake Mikazuki (north Hokkaido in north Japan), Lake Chokai (north of Honshu), and Lake Mikuriga (central part of Honshu). Pb isotopic comparison of collected core sediment and previously reported data for wet precipitation and aerosols from different Asian regions indicate that, before 1900, Pb accumulated in these three lakes was not affected by trans-boundary sources. Lake Mikazuki started to receive Pb emissions from Russia in early 1900s, and during the last two decades, this lake has been affected by trans-boundary Pb pollution from northern China. Lake Chokai has received Pb pollutant from northern China since early 1900s until 2009, whereas for the Lake Mikuriga the major Pb contaminant was transported from southern China during the past 100 years. The results of our study demonstrate that Japan Archipelago has received trans-boundary Pb emissions from different parts of East Asian region depending on location, and the major source region has changed historically. - Highlights: • Historical trend of Pb pollution was recorded in six Japanese Lakes. • Pb concentration and Pb isotope ratios were determined for sediment cores. • High [Pb] and less radiogenic Pb isotope ratios

  10. Historical record of lead accumulation and source in the tidal flat of Haizhou Bay, Yellow Sea: Insights from lead isotopes

    International Nuclear Information System (INIS)

    Zhang, Rui; Guan, Minglei; Shu, Yujie; Shen, Liya; Chen, Xixi; Zhang, Fan; Li, Tiegang

    2016-01-01

    In order to investigate the historical records of lead contamination and source in coastal region of Haizhou Bay, Yellow Sea, a sediment core was collected from tidal flat, dated by 210 Pb and 137 Cs. Lead and its stable isotopic ratios were determined. The profiles of enrichment factor (EF) and Pb isotope ratios showed increasing trend upward throughout the core, correlating closely with the experience of a rapid economic and industrial development of the catchment. According to Pb isotopic ratios, coal combustion emission mainly contributed to the Pb burden in sediments. Based on end-member model, coal combustion emission dominated anthropogenic Pb sources in recent decades contributing from 48% to 67% in sediment. And the contribution of leaded gasoline was lower than 20%. A stable increase of coal combustion source was found in sediment core, while the contribution of leaded gasoline had declined recently, with the phase-out of leaded gasoline in China. - Highlights: •Pb contamination in tidal flat of Haizhou Bay was chronicled by a sediment core. •The coal combustion source dominated Pb contamination of Haizhou Bay. •Coal combustion source showed an increasing trend in four decades in Haizhou Bay.

  11. Coral-based history of lead and lead isotopes of the surface Indian Ocean since the mid-20th century

    Science.gov (United States)

    Lee, Jong-Mi; Boyle, Edward A.; Suci Nurhati, Intan; Pfeiffer, Miriam; Meltzner, Aron J.; Suwargadi, Bambang

    2014-07-01

    Anthropogenic lead (Pb) from industrial activities has greatly altered the distribution of Pb in the present-day oceans, but no continuous temporal Pb evolution record is available for the Indian Ocean despite rapidly emerging industries around the region. Here, we present the coral-inferred annual history of Pb concentration and isotope ratios in the surface Indian Ocean since the mid-20th century (1945-2010). We analyzed Pb in corals from the Chagos Archipelago, western Sumatra and Strait of Singapore - which represent the central Indian Ocean via nearshore sites. Overall, coral Pb/Ca increased in the mid-1970s at all the sites. However, coral Pb isotope ratios evolve distinctively at each site, suggesting Pb contamination arises from different sources in each case. The major source of Pb in the Chagos coral appears to be India's Pb emission from leaded gasoline combustion and coal burning, whereas Pb in western Sumatra seems to be largely affected by Indonesia's gasoline Pb emission with additional Pb inputs from other sources. Pb in the Strait of Singapore has complex sources and its isotopic composition does not reflect Pb from leaded gasoline combustion. Higher 206Pb/207Pb and 208Pb/207Pb ratios found at this site may reflect the contribution of Pb from coals and ores from southern China, Indonesia, and Australia, and local Pb sources in the Strait of Singapore. It is also possible that the Pb isotope ratios of Singapore seawater were elevated through isotope exchange with natural fluvial particles considering its delta setting.

  12. Linking cases of illegal shootings of the endangered California condor using stable lead isotope analysis

    Energy Technology Data Exchange (ETDEWEB)

    Finkelstein, Myra E., E-mail: myraf@ucsc.edu [Microbiology and Environmental Toxicology Department, University of California, Santa Cruz, CA 95064 (United States); Kuspa, Zeka E. [Microbiology and Environmental Toxicology Department, University of California, Santa Cruz, CA 95064 (United States); Welch, Alacia [National Park Service, Pinnacles National Park, 5000 Highway 146, Paicines, CA 95043 (United States); Eng, Curtis; Clark, Michael [Los Angeles Zoo and Botanical Gardens, 5333 Zoo Drive, Los Angeles, CA 90027 (United States); Burnett, Joseph [Ventana Wildlife Society, 19045 Portola Dr. Ste. F-1, Salinas, CA 93908 (United States); Smith, Donald R. [Microbiology and Environmental Toxicology Department, University of California, Santa Cruz, CA 95064 (United States)

    2014-10-15

    Lead poisoning is preventing the recovery of the critically endangered California condor (Gymnogyps californianus) and lead isotope analyses have demonstrated that ingestion of spent lead ammunition is the principal source of lead poisoning in condors. Over an 8 month period in 2009, three lead-poisoned condors were independently presented with birdshot embedded in their tissues, evidencing they had been shot. No information connecting these illegal shooting events existed and the timing of the shooting(s) was unknown. Using lead concentration and stable lead isotope analyses of feathers, blood, and recovered birdshot, we observed that: i) lead isotope ratios of embedded shot from all three birds were measurably indistinguishable from each other, suggesting a common source; ii) lead exposure histories re-constructed from feather analysis suggested that the shooting(s) occurred within the same timeframe; and iii) two of the three condors were lead poisoned from a lead source isotopically indistinguishable from the embedded birdshot, implicating ingestion of this type of birdshot as the source of poisoning. One of the condors was subsequently lead poisoned the following year from ingestion of a lead buckshot (blood lead 556 µg/dL), illustrating that ingested shot possess a substantially greater lead poisoning risk compared to embedded shot retained in tissue (blood lead ∼20 µg/dL). To our knowledge, this is the first study to use lead isotopes as a tool to retrospectively link wildlife shooting events. - Highlights: • We conducted a case-based analysis of illegal shootings of California condors. • Blood and feather Pb isotopes were used to reconstruct the illegal shooting events. • Embedded birdshot from the three condors had the same Pb isotope ratios. • Feather and blood Pb isotopes indicated that the condors were shot in a common event. • Ingested shot causes substantially greater lead exposure compared to embedded shot.

  13. Comparison of gas chromatography/isotope ratio mass spectrometry and liquid chromatography/isotope ratio mass spectrometry for carbon stable-isotope analysis of carbohydrates

    NARCIS (Netherlands)

    Moerdijk-Poortvliet, Tanja C. W.; Schierbeek, Henk; Houtekamer, Marco; van Engeland, Tom; Derrien, Delphine; Stal, Lucas J.; Boschker, Henricus T. S.

    2015-01-01

    We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of δ(13)C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence, although

  14. Comparison of gas chromatography/isotope ratio mass spectrometry and liquid chromatography/isotope ratio mass spectrometry for carbon stable-isotope analysis of carbohydrates

    NARCIS (Netherlands)

    Moerdijk-Poortvliet, T.C.W.; Schierbeek, H.; Houtekamer, M.; van Engeland, T.; Derrien, D.; Stal, L.J.; Boschker, H.T.S.

    2015-01-01

    We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of d13C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence, although

  15. Comparison of gas chromatography/isotope ratio mass spectrometry and liquid chromatography/isotope ratio mass spectrometry for carbon stable-isotope analysis of carbohydrates

    NARCIS (Netherlands)

    Moerdijk-Poortvliet, T.C.W.; Schierbeek, H.; Houtekamer, M.; van Engeland, T.; Derrien, D.; Stal, L.J.; Boschker, H.T.S.

    2015-01-01

    Rationale: We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of δ13C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence,

  16. Stable oxygen and hydrogen isotopes of brines - comparing isotope ratio mass spectrometry and isotope ratio infrared spectroscopy

    Science.gov (United States)

    Ahrens, Christian; Koeniger, Paul; van Geldern, Robert; Stadler, Susanne

    2013-04-01

    Today's standard analytical methods for high precision stable isotope analysis of fluids are gas-water equilibration and high temperature pyrolysis coupled to isotope ratio mass spectrometers (IRMS). In recent years, relatively new laser-based analytical instruments entered the market that are said to allow high isotope precision data on nearly every media. This optical technique is referred to as isotope ratio infrared spectroscopy (IRIS). The objective of this study is to evaluate the capability of this new instrument type for highly saline solutions and a comparison of the analytical results with traditional IRMS analysis. It has been shown for the equilibration method that the presence of salts influences the measured isotope values depending on the salt concentration (see Lécuyer et al, 2009; Martineau, 2012). This so-called 'isotope salt effect' depends on the salt type and salt concentration. These factors change the activity in the fluid and therefore shift the isotope ratios measured by the equilibration method. Consequently, correction factors have to be applied to these analytical data. Direct conversion techniques like pyrolysis or the new laser instruments allow the measurement of the water molecule from the sample directly and should therefore not suffer from the salt effect, i.e. no corrections of raw values are necessary. However, due to high salt concentrations this might cause technical problems with the analytical hardware and may require labor-intensive sample preparation (e.g. vacuum distillation). This study evaluates the salt isotope effect for the IRMS equilibration technique (Thermo Gasbench II coupled to Delta Plus XP) and the laser-based IRIS instruments with liquid injection (Picarro L2120-i). Synthetic salt solutions (NaCl, KCl, CaCl2, MgCl2, MgSO4, CaSO4) and natural brines collected from the Stassfurt Salt Anticline (Germany; Stadler et al., 2012) were analysed with both techniques. Salt concentrations ranged from seawater salinity

  17. Lead isotope ratios in lichen samples evaluated by ICP-ToF-MS to assess possible atmospheric pollution sources in Havana, Cuba.

    Science.gov (United States)

    Alvarez, Alfredo Montero; Estévez Alvarez, Juan R; do Nascimento, Clístenes Williams Araújo; González, Iván Pupo; Rizo, Oscar Díaz; Carzola, Lázaro Lima; Torres, Roberto Ayllón; Pascual, Jorge Gómez

    2017-01-01

    Epiphytic lichens, collected from 119 sampling sites grown over "Roistonea Royal Palm" trees, were used to assess the spatial distribution pattern of lead (Pb) and identify possible pollution sources in Havana (Cuba). Lead concentrations in lichens and topsoils were determined by flame atomic absorption spectrophotometry and inductively coupled plasma (ICP) atomic emission spectrometry, respectively, while Pb in crude oils and gasoline samples were measured by ICP-time of flight mass spectrometry (ICP-ToF-MS). Lead isotopic ratios measurements for lichens, soils, and crude oils were obtained by ICP-ToF-MS. We found that enrichment factors (EF) reflected a moderate contamination for 71% of the samples (EF > 10). The 206 Pb/ 207 Pb ratio values for lichens ranged from 1.17 to 1.20 and were a mixture of natural radiogenic and industrial activities (e.g., crude oils and fire plants). The low concentration of Pb found in gasoline (leaded gasoline is no longer used in Cuba.

  18. Determination of trace element concentrations and stable lead, uranium and thorium isotope ratios by quadrupole-ICP-MS in NORM and NORM-polluted sample leachates

    International Nuclear Information System (INIS)

    Mas, J.L.; Villa, M.; Hurtado, S.; García-Tenorio, R.

    2012-01-01

    Highlights: ► Polluted sediment and NORM samples. ► An efficient yet fast process allowing multi-parametric determinations in 206 Pb/ 207 Pb/ 208 Pb, 238 U/ 234 U and 232 Th/ 230 Th isotope ratios using a single sample aliquot and a single instrument (ICP-QMS). Eichrom UTEVA ® extraction chromatography minicolumns were used to separate uranium and thorium in sample leachates. Independent ICP-MS determinations of uranium and thorium isotope ratios were carried out afterwards. Previously a small aliquot of the leachate was used for the determination of trace element concentrations and lead isotope ratios. Several radiochemical arrangements were tested to get maximum performances and simplicity of the method. The performances of the method were studied in terms of chemical yields of uranium and thorium and removal of the potentially interfering elements. The established method was applied to samples from a chemical industry and sediments collected in a NORM-polluted scenario. The results obtained from our method allowed us to infer not only the extent, but also the sources of the contamination in the area.

  19. Stable lead isotopes as a tracer in coastal waters

    International Nuclear Information System (INIS)

    Stukas, V.J.; Wong, C.S.

    1981-01-01

    The natural abundances of the stable isotopes of lead are used to identify natural and industrial sources of lead in the coastal waters of British Columbia, Canada. The 206 Pb/ 207 Pb ratios, used to characterize the lead source, had values of approx. 1.24 for coastal oceanic water, approx. 1.22 for fjord waters receiving lead from mine tailings, and approx. 1.163 for waters near urban centers. The lead concentration data are in agreement with presently accepted seawater values

  20. Accurate isotope ratio mass spectrometry. Some problems and possibilities

    International Nuclear Information System (INIS)

    Bievre, P. de

    1978-01-01

    The review includes reference to 190 papers, mainly published during the last 10 years. It covers the following: important factors in accurate isotope ratio measurements (precision and accuracy of isotope ratio measurements -exemplified by determinations of 235 U/ 238 U and of other elements including 239 Pu/ 240 Pu; isotope fractionation -exemplified by curves for Rb, U); applications (atomic weights); the Oklo natural nuclear reactor (discovered by UF 6 mass spectrometry at Pierrelatte); nuclear and other constants; isotope ratio measurements in nuclear geology and isotope cosmology - accurate age determination; isotope ratio measurements on very small samples - archaeometry; isotope dilution; miscellaneous applications; and future prospects. (U.K.)

  1. Lead contamination and transfer in urban environmental compartments analyzed by lead levels and isotopic compositions

    International Nuclear Information System (INIS)

    Hu, Xin; Sun, Yuanyuan; Ding, Zhuhong; Zhang, Yun; Wu, Jichun; Lian, Hongzhen; Wang, Tijian

    2014-01-01

    Lead levels and isotopic compositions in atmospheric particles (TSP and PM 2.5 ), street dust and surface soil collected from Nanjing, a mega city in China, were analyzed to investigate the contamination and the transfer of lead in urban environmental compartments. The lead contents in TSP and PM 2.5 are significantly higher than them in the surface soil and street dust (p  206 Pb/ 207 Pb vs. 208 Pb/ 206 Pb and 206 Pb/ 207 Pb vs. 1/Pb imply that the street dust and atmospheric particles (TSP and PM 2.5 ) have very similar lead sources. Coal emissions and smelting activities may be the important lead sources for street dust and atmospheric particles (TSP and PM 2.5 ), while the deposition of airborne lead is an important lead source for urban surface soil. - Highlights: • Lead levels and isotope ratios in atmospheric particles, street dust and surface soil. • Significant enrichment of lead in atmospheric particles was observed. • Street dust and atmospheric particles have similar lead sources. • Endmembers of soil lead differ from street dust and atmospheric particles. • Airborne lead poses the main risks to unban environmental quality. - Transfer of airborne particle bound lead into street dust and surface soil in unban environmental based on lead levels and isotopic compositions

  2. A fast atom bombardment study of the lead isotope ratios in early nineteenth century Niagara Peninsula pottery glazes

    International Nuclear Information System (INIS)

    Miller, J.M.; Jones, T.R.B.; Kenney, Tina; Rupp, D.W.

    1986-01-01

    The application of fast atom bombardment (FAB) mass spectrometry to the determination of lead isotope ratios in nineteenth century pottery glazes from the Niagara Peninsula has been investigated with the aim of determining the source of the lead used in the glazes. Methods of sampling have been compared, including direct analysis of glass chips, analysis of powdered glaze scrapings, analysis of acid extracts of the former, and simple acid leaching of the surface of a piece of pottery. The latter method gave the best results. The FAB data, as obtained on an older mass spectrometer, can distinguish lead from igneous vs. sedimentary deposits, but is not adequate to determine specific mining locations. Although newer FAB instrumentation can narrow this range, the overlap of data from the Niagara Peninsula and England precludes a simple answer to the archeological question as to English vs. Canadian origin of the lead used in the Jordan pottery glazes. However, the data do suggest that the potter used a local source for the lead

  3. Isotope ratio in stellar atmospheres and nucleosynthesis

    International Nuclear Information System (INIS)

    Barbuy, B.L.S.

    1987-01-01

    The determination of isotopic ratios in stellar atmospheres is studied. The isotopic shift of atomic and molecular lines of different species of a certain element is examined. CH and MgH lines are observed in order to obtain the 12 C: 13 C and 24 Mg: 25 Mg: 26 Mg isotpic ratios. The formation of lines in stellar atmospheres is computed and the resulting synthetic spectra are employed to determine the isotopic abundances. The results obtained for the isotopic ratios are compared to predictions of nucleosynthesis theories. Finally, the concept of primary and secondary element is discussed, and these definitions are applied to the observed variations in the abundance of elements as a function of metallicity. (author) [pt

  4. Stable isotope ratio mass spectrometry in forensic science and food adulteration research

    International Nuclear Information System (INIS)

    Kumar, B.

    2009-01-01

    Stable Isotope Ratio Mass Spectrometry (SIRMS) is an established technique for the determination of origin of geological, biological, chemical and physio-chemical samples/materials. With the development of highly precise mass spectrometers, the stable isotope ratio determination of hydrogen, carbon, nitrogen and oxygen have gained considerable interest in the fields of forensic science and food authentication. Natural variations in the isotopic composition of lighter elements occur due to fractionation effects, resulting in the finger printing of specific isotope ratio values that are characteristic of the origin, purity, and manufacturing processes of the products and their constituents. Forensic science uses scientific and technical methods to investigate traceable evidence of criminal acts. Stable isotope ratio mass spectrometry has been applied to numerous aspects of the forensic science. The analysis of explosives such as ammonium nitrate, gun powder and tri-nitro-toluene (TNT), cases of murder, armed robbery, drug smuggling, terrorism, arson and hit and run traffic accidents are a few of them. The main types of geological evidences in such cases are mud, soil, rocks, sand, gravel, dust particles, biological materials, organic particles and anthropogenic components. Stable isotopes are used as tools to corroborate and confirm the evidential leads in the investigation of such crimes. The variation in natural abundances of carbon and nitrogen and their isotopic ratios δ 13 C and δ 15 N can identify links between items found at crime scene with those of suspect. The paper discusses the applications of SIRMS in the field of forensic science and food adulteration research

  5. Isotopic analysis of bullet lead samples

    International Nuclear Information System (INIS)

    Sankar Das, M.; Venkatasubramanian, V.S.; Sreenivas, K.

    1976-01-01

    The possibility of using the isotopic composition of lead for the identification of bullet lead is investigated. Lead from several spent bullets were converted to lead sulphide and analysed for the isotopic abundances using an MS-7 mass spectrometer. The abundances are measured relative to that for Pb 204 was too small to permit differentiation, while the range of variation of Pb 206 and Pb 207 and the better precision in their analyses permitted differentiating samples from one another. The correlation among the samples examined has been pointed out. The method is complementary to characterisation of bullet leads by the trace element composition. The possibility of using isotopically enriched lead for tagging bullet lead is pointed out. (author)

  6. Discriminating background from anthropogenic lead by isotopic methods

    International Nuclear Information System (INIS)

    Nelson, B.K.; O'Brien, H.E.

    1995-01-01

    The goal of this pilot project was to evaluate the practicality of using natural variations in the isotopic composition of lead to test for the presence of anthropogenic lead in soil, surface water and ground water. Complex chemical reactions in the environment may cause measured lead concentrations to be ambiguous indicators of anthropogenic lead component. The lead isotope tracer technique has the potential to identify both the presence and proportion of anthropogenic lead in the environment. The tested the lead isotope technique at Eielson Air Force Base, Alaska, on sources of suspected fuel contamination. Although the results are specific to this base, the general technique of using lead isotopes to trace the movement of anthropogenic lead is applicable to other CERCLA sites. The study had four objectives: (1) characterize the natural lead isotope composition of bedrock, stream sediment and soils; (2) characterize the isotopic composition of the contaminant lead derived from fuel; (3) evaluate the sensitivity of the isotopic method to distinguishing between anthropogenic and natural lead in soil and water samples and (4) evaluate the analytical feasibility and accuracy of the method at the Isotope Geochemistry Laboratory at the University of Washington

  7. Regional lead isotope study of a polluted river catchment: River Wear, Northern England, UK

    International Nuclear Information System (INIS)

    Shepherd, Thomas J.; Chenery, Simon R.N.; Pashley, Vanessa; Lord, Richard A.; Ander, Louise E.; Breward, Neil; Hobbs, Susan F.; Horstwood, Matthew; Klinck, Benjamin A.; Worrall, Fred

    2009-01-01

    High precision, lead isotope analyses of archived stream sediments from the River Wear catchment, northeast England (1986-88), provide evidence for three main sources of anthropogenic lead pollution; lead mining, industrial lead emissions and leaded petrol. In the upper catchment, pollution is totally controlled and dominated by large lead discharges from historic mining centres in the North Pennine Orefield ( 208 Pb/ 206 Pb, 207 Pb/ 206 Pb ratios range from 2.0744-2.0954 and 0.8413-0.8554 respectively). In the lower catchment, co-extensive with the Durham Coalfield and areas of high population density, pollution levels are lower and regionally more uniform. Isotope ratios are systematically higher than in the upper catchment ( 208 Pb/ 206 Pb, 207 Pb/ 206 Pb ratios range from 2.0856-2.1397 and 0.8554-0.8896 respectively) and far exceed values determined for the geogenic regional background. Here, the pollution is characterised by the atmospheric deposition of industrial lead and petrol lead. Lead derived from the combustion of coal, although present, is masked by the other two sources. Recent sediments from the main channel of the River Wear are isotopically indistinguishable from older, low order stream sediments of the North Pennine Orefield, indicating that contamination of the river by lead mining waste (up to several 1000 mg/kg Pb at some locations) continues to pose an environmental problem; a pattern that can be traced all the way to the tidal reach. Using within-catchment isotope variation and sediment lead concentrations, estimates can be made of the discharges from discrete mines or groups of mines to the overall level of lead pollution in the River Wear. As well as providing information pertinent to source apportionment and on-going catchment remediation measures, the database is a valuable resource for epidemiologists concerned with the health risks posed by environmental lead.

  8. Investigating the origin of Pb pollution in a terrestrial soil-plant-snail food chain by means of Pb isotope ratios.

    NARCIS (Netherlands)

    Notten, M.J.M.; Walraven, N.; Beets, K.; Vroon, P.; Rozema, J.; Aerts, R.

    2008-01-01

    Lead isotope ratios were used to trace the origin of Pb in a soil-plant (Urtica dioica)-snail (Cepaea nemoralis) food chain in two polluted locations in the floodplains of the rivers Meuse and Rhine (Biesbosch National Park) and one reference location in the Netherlands. Lead isotope ratios and

  9. Finite mixture models for the computation of isotope ratios in mixed isotopic samples

    Science.gov (United States)

    Koffler, Daniel; Laaha, Gregor; Leisch, Friedrich; Kappel, Stefanie; Prohaska, Thomas

    2013-04-01

    Finite mixture models have been used for more than 100 years, but have seen a real boost in popularity over the last two decades due to the tremendous increase in available computing power. The areas of application of mixture models range from biology and medicine to physics, economics and marketing. These models can be applied to data where observations originate from various groups and where group affiliations are not known, as is the case for multiple isotope ratios present in mixed isotopic samples. Recently, the potential of finite mixture models for the computation of 235U/238U isotope ratios from transient signals measured in individual (sub-)µm-sized particles by laser ablation - multi-collector - inductively coupled plasma mass spectrometry (LA-MC-ICPMS) was demonstrated by Kappel et al. [1]. The particles, which were deposited on the same substrate, were certified with respect to their isotopic compositions. Here, we focus on the statistical model and its application to isotope data in ecogeochemistry. Commonly applied evaluation approaches for mixed isotopic samples are time-consuming and are dependent on the judgement of the analyst. Thus, isotopic compositions may be overlooked due to the presence of more dominant constituents. Evaluation using finite mixture models can be accomplished unsupervised and automatically. The models try to fit several linear models (regression lines) to subgroups of data taking the respective slope as estimation for the isotope ratio. The finite mixture models are parameterised by: • The number of different ratios. • Number of points belonging to each ratio-group. • The ratios (i.e. slopes) of each group. Fitting of the parameters is done by maximising the log-likelihood function using an iterative expectation-maximisation (EM) algorithm. In each iteration step, groups of size smaller than a control parameter are dropped; thereby the number of different ratios is determined. The analyst only influences some control

  10. Lead isotope identification of sources of galena from some prehistoric Indian sites in Ontario, Canada

    International Nuclear Information System (INIS)

    Farquhar, R.M.; Fletcher, I.R.

    1980-01-01

    Lead isotopic compositions of 12 galenas from five late Archaic-initial Woodland grave and habitation sites in southern Ontario have made it possible to determine the most likely source areas for the galenas. For one of the oldest sites (Finlan), the most likely source is in the southwestern Upper Mississippi Valley (Wisconsin-Illinois-Iowa) mineral district. The seven Finlan galenas exhibit a range of isotopic ratios; three of the largest specimens have substantial isotopic variations (up to 1.8% in the ratio of lead-207 to lead-206) on a scale of a few centimeters. This suggests that the lead isotopic zoning ascribed to the Upper Mississippi Valley area is not sufficiently well defined to enable us to determine if all the Finlan samples were derived from a single mineral deposit. Galenas from the other sites (Constance Bay, Hind, Bruce Boyd, and Picton) most probably originated in the southeastern Ontario-northwestern New York area. Isotopic differences among the Constance Bay, Hind, and Bruce Boyd galenas, on the one hand, and the Picton galena, on the other, suggest that at least two distinct sources in that region were exploited

  11. Tracing the anthropogenic lead sources in coastal sediments of SE-Pacific (36 deg. Lat. S) using stable lead isotopes

    International Nuclear Information System (INIS)

    Munoz, Praxedes N.V.; Garbe-Schoenberg, Carl-Dieter; Salamanca, Marco A.

    2004-01-01

    This study evaluates the main sources of antropogenic Pb in one of the most industrialized centers of the southern Chilean coast (36 deg. S). Stable lead isotopes ( 206 Pb/ 207 Pb, 208 Pb/ 207 Pb) were used to trace main Pb sources to coastal sediments, considering the suspended particulate matter (SPM) from marine (traps), continental (rivers) and industrial effluents, sediments and leaded gasoline samples. The atmospheric input was evaluated through natural collectors; i.e. Raqui-Tubul salt marsh. Results show that marine samples lie on a trend between industrial effluents (∼1.16, 2.44) and natural sources (1.20, 2.50), not related to gasoline consumption. Salt marsh sediments show comparable isotopic composition to marine samples, suggesting the importance of the atmospheric input in the coastal sediments, not related to the leaded gasoline composition either. The continental input (1.18, 2.48) is highly influenced by precipitation, being difficult to separate both sources (atmosphere and continental runoff), showing also similar isotopic ratio to marine sediments. The signal of industrial emissions is masked with the introduction of Pb with higher isotopic ratios, compared to the values observed in the material collected from traps (SPM ∼1.19, 2.48). The contribution of more radiogenic Pb by the upwelling is suggested

  12. Precise and accurate isotope ratio measurements by ICP-MS.

    Science.gov (United States)

    Becker, J S; Dietze, H J

    2000-09-01

    The precise and accurate determination of isotope ratios by inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS (LA-ICP-MS) is important for quite different application fields (e.g. for isotope ratio measurements of stable isotopes in nature, especially for the investigation of isotope variation in nature or age dating, for determining isotope ratios of radiogenic elements in the nuclear industry, quality assurance of fuel material, for reprocessing plants, nuclear material accounting and radioactive waste control, for tracer experiments using stable isotopes or long-lived radionuclides in biological or medical studies). Thermal ionization mass spectrometry (TIMS), which used to be the dominant analytical technique for precise isotope ratio measurements, is being increasingly replaced for isotope ratio measurements by ICP-MS due to its excellent sensitivity, precision and good accuracy. Instrumental progress in ICP-MS was achieved by the introduction of the collision cell interface in order to dissociate many disturbing argon-based molecular ions, thermalize the ions and neutralize the disturbing argon ions of plasma gas (Ar+). The application of the collision cell in ICP-QMS results in a higher ion transmission, improved sensitivity and better precision of isotope ratio measurements compared to quadrupole ICP-MS without the collision cell [e.g., for 235U/238U approximately 1 (10 microg x L(-1) uranium) 0.07% relative standard deviation (RSD) vs. 0.2% RSD in short-term measurements (n = 5)]. A significant instrumental improvement for ICP-MS is the multicollector device (MC-ICP-MS) in order to obtain a better precision of isotope ratio measurements (with a precision of up to 0.002%, RSD). CE- and HPLC-ICP-MS are used for the separation of isobaric interferences of long-lived radionuclides and stable isotopes by determination of spallation nuclide abundances in an irradiated tantalum target.

  13. Variations of lead isotopes and airborne particulate concentrations from the Kozani basin, West Macedonia, Greece.

    Science.gov (United States)

    Charalampides, G; Manoliadis, O; Triantafyllou, A

    2002-03-01

    The spread and variation in 206Pb/207Pb ratios make Pb isotopes a powerful tool when it comes to detecting trends in airborne particulates originating mainly from power plants. This study was conducted to determine the source of pollution in Kozani area, an affected industrial area. Lead isotopic ratios of air filters under certain meteorological conditions were compared to Pb isotope analyses sampled from lignite mines, but also to Pb isotope analyses of cultivations in soil originating from the reclamation of old abandoned lignite-mines. The particles taken into consideration have an aerodynamic diameter less than 10 microm (PM10). The measurements were carried out in a central part of the town of Kozani, West Macedonia, for one year observation period. The lead isotope values of air filters and of wheat in the Kozani area are between the values of lignite Pb and of Greek gasoline.

  14. Lead isotopes as an environmental indicator of pollution sources

    International Nuclear Information System (INIS)

    Aaberg, G.; Pacyna, J.; Stray, H.

    1997-02-01

    An interesting question when determining and quantifying pollution is the characterisation of the sources. Also, is the pollution locally derived or is it longtransported? Analyses of Pb isotope ratios and Pb concentrations on airfilter from Oslo, Norway, together with analyses of coal of different origin and wood, show that the decrease in total Pb in the first half of the 1990's is not due only to the reduction of leaded petrol but that there are other important sources for the pollution which have been cut down. The reduction in emissions from coal burning in Europe can be seen on airfilter from Oslo and also the following reduction in leaded petrol. An isotopic study of lead on airfilter from the countryside outside Oslo implies that the finer particles have been atmospherically long transported while the coarser particles are of a more local origin, e.g. from domestic burning of wood. The above results show that the use of a natural isotopic system like Pb is a powerful tool for e.g. the determination of pollution, routes of its transportation, for the monitoring of processes of the present, and for provenance determinations. 7 refs., 8 figs., 2 tabs

  15. Evaluating lead isotope data: further observations

    International Nuclear Information System (INIS)

    Budd, P.; Gale, D.; Pollard, A.M.; Thomas, R.G.; Williams, P.A.

    1993-01-01

    In this paper analytical data, relating to the lead isotope composition of mineral deposits in the Taurus mountain region of Turkey, is evaluated. The importance of lead isotope studies to the evidence as to the origin of prehistoric metal artefacts is discussed. (UK)

  16. Determining lead sources in Mexico using the lead isotope ratio La identificación de fuentes de exposición a plomo en México a través de la determinación de la razón de isótopos de plomo

    Directory of Open Access Journals (Sweden)

    Madhu Chaudhary-Webb

    2003-01-01

    Full Text Available OBJECTIVE: Lead poisoning can, in some cases, be traced to a specific route or source of exposure on the basis of the individual's blood lead isotope ratio. To assess the major source of lead exposure among women residing in Mexico City, we compared blood, ceramic, and gasoline lead isotope ratios. MATERIAL AND METHODS: The study population, randomly selected from participants of a large trial, (1/1996-12/1996 comprised of 16 women whose lead levels exceeded 10 µg/dl and who reported using lead-glazed ceramics. Lead isotope ratios were performed on a Perkin Elmer 5000 Inductively Coupled Plasma Mass Spectrometer (ICP-MS interfaced with a Perkin Elmer HGA-600MS Electrothermal Vaporization System (ETV. RESULTS: The isotope ratios (206Pb/204Pb, 207Pb/204Pb, and 208Pb/204Pb of both the blood specimens and their corresponding ceramic specimens were highly correlated, with r=0.9979, r²=0.9958, r=0.9957, r²=0.9915 and r=0.9945, r²=0.9890 values for the three isotope ratios, respectively, suggesting that the lead exposure most likely resulted from the use of these ceramic. Measurements of lead isotope ratios from leaded gasoline in use at the time of blood sampling, differed from those in blood and ceramics. CONCLUSIONS: Determining lead isotope ratios can be an efficient tool to identify a major source of lead exposure and to support the implementation of public health prevention and control measures.OBJETIVO: Identificar la fuente principal de exposición a plomo entre mujeres residentes en la Ciudad de México, por medio de la comparación de las razones de isótopos de plomo en sangre, cerámica y gasolina. MATERIAL Y MÉTODOS: La población de estudio fue seleccionada aleatoriamente de participantes de una muestra obtenida de enero a diciembre de 1996 y consistió en 16 mujeres con niveles de plomo mayores a 10 µg/dl, que usaban cerámica vidriada con plomo. Las razones de isótopos de plomo se obtuvieron con un espectrómetro de masa de

  17. Deformation properties of lead isotopes

    International Nuclear Information System (INIS)

    Tolokonnikov, S. V.; Borzov, I. N.; Lutostansky, Yu. S.; Saperstein, E. E.

    2016-01-01

    The deformation properties of a long lead isotopic chain up to the neutron drip line are analyzed on the basis of the energy density functional (EDF) in the FaNDF 0 Fayans form. The question of whether the ground state of neutron-deficient lead isotopes can have a stable deformation is studied in detail. The prediction of this deformation is contained in the results obtained on the basis of the HFB-17 and HFB-27 Skyrme EDF versions and reported on Internet. The present analysis reveals that this is at odds with experimental data on charge radii and magnetic moments of odd lead isotopes. The Fayans EDF version predicts a spherical ground state for all light lead isotopes, but some of them (for example, 180 Pb and 184 Pb) prove to be very soft—that is, close to the point of a phase transition to a deformed state. Also, the results obtained in our present study are compared with the predictions of some other Skyrme EDF versions, including SKM*, SLy4, SLy6, and UNE1. By and large, their predictions are closer to the results arising upon the application of the Fayans functional. For example, the SLy4 functional predicts, in just the same way as the FaNDF 0 functional, a spherical shape for all nuclei of this region. The remaining three Skyrme EDF versions lead to a deformation of some light lead isotopes, but their number is substantially smaller than that in the case of the HFB-17 and HFB-27 functionals. Moreover, the respective deformation energy is substantially lower, which gives grounds to hope for the restoration of a spherical shape upon going beyond the mean-field approximation, which we use here. Also, the deformation properties of neutron-rich lead isotopes are studied up to the neutron drip line. Here, the results obtained with the FaNDF 0 functional are compared with the predictions of the HFB-17, HFB-27, SKM*, and SLy4 Skyrme EDF versions. All of the EDF versions considered here predict the existence of a region where neutron-rich lead isotopes undergo

  18. Regional lead isotope study of a polluted river catchment: River Wear, Northern England, UK

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, Thomas J., E-mail: shepherdtj@aol.com [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom); Chenery, Simon R.N. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Pashley, Vanessa [NERC Isotope Geosciences Laboratory, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (United Kingdom); Lord, Richard A. [School of Science and Technology, University of Teesside, Middlesbrough, Tees Valley TS1 3BA (United Kingdom); Ander, Louise E.; Breward, Neil; Hobbs, Susan F. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Horstwood, Matthew [NERC Isotope Geosciences Laboratory, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG (United Kingdom); Klinck, Benjamin A. [British Geological Survey, Nicker Hill, Keyworth, Nottingham NG12 5GG (United Kingdom); Worrall, Fred [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom)

    2009-08-15

    High precision, lead isotope analyses of archived stream sediments from the River Wear catchment, northeast England (1986-88), provide evidence for three main sources of anthropogenic lead pollution; lead mining, industrial lead emissions and leaded petrol. In the upper catchment, pollution is totally controlled and dominated by large lead discharges from historic mining centres in the North Pennine Orefield ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios range from 2.0744-2.0954 and 0.8413-0.8554 respectively). In the lower catchment, co-extensive with the Durham Coalfield and areas of high population density, pollution levels are lower and regionally more uniform. Isotope ratios are systematically higher than in the upper catchment ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios range from 2.0856-2.1397 and 0.8554-0.8896 respectively) and far exceed values determined for the geogenic regional background. Here, the pollution is characterised by the atmospheric deposition of industrial lead and petrol lead. Lead derived from the combustion of coal, although present, is masked by the other two sources. Recent sediments from the main channel of the River Wear are isotopically indistinguishable from older, low order stream sediments of the North Pennine Orefield, indicating that contamination of the river by lead mining waste (up to several 1000 mg/kg Pb at some locations) continues to pose an environmental problem; a pattern that can be traced all the way to the tidal reach. Using within-catchment isotope variation and sediment lead concentrations, estimates can be made of the discharges from discrete mines or groups of mines to the overall level of lead pollution in the River Wear. As well as providing information pertinent to source apportionment and on-going catchment remediation measures, the database is a valuable resource for epidemiologists concerned with the health risks posed by environmental lead.

  19. How the oxygen isotope ratio of rain water influences the isotope ratio of chicken eggshell carbonate

    Science.gov (United States)

    Price, Gregory; Grimes, Stephen

    2015-04-01

    The stable oxygen isotope ratio of chicken eggshell carbonate was analysed from chicken eggs laid under free range, and organic farming regimes from across the UK. The eggshell carbonate oxygen isotope data shows a clear depletion in delta18O distribution from the southwest to the northeast. Although consistently offset by around 1 permil, the same isotopic distribution as that seen in eggshell carbonate is observed in the delta18O ratio of rainfall and groundwater from across the UK. This distribution is related to the Rayleigh distillation of rainfall driven by westerly winds across the UK landmass. The clear relationship observed between eggshell delta18O values and that of rainwater presumably reflects the nature of free range chickens which must be drinking locally derived rainwater and supplementing their diet and water intake with locally derived food. These results suggest that the oxygen isotope value of chicken eggshells can be used as a forensic tool to identify the locality that free range and organic eggs were laid within the UK. Furthermore, if suitable material is preserved in the archaeological and geological record then such a relationship can potentially be used to establish the oxygen isotope value of rainwater from which ancient and / or ancestral birds lived.

  20. Liquid and gas chromatography coupled to isotope ratio mass spectrometry for the determination of 13C-valine isotopic ratios in complex biological samples

    NARCIS (Netherlands)

    Godin, Jean-Philippe; Breuillé, Denis; Obled, Christiane; Papet, Isabelle; Schierbeek, Henk; Hopfgartner, Gérard; Fay, Laurent-Bernard

    2008-01-01

    On-line gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is commonly used to measure isotopic ratios at natural abundance as well as for tracer studies in nutritional and medical research. However, high-precision (13)C isotopic enrichment can also be measured by liquid

  1. On the cross-sensitivity between water vapor mixing ratio and stable isotope measurements of in-situ analyzers

    KAUST Repository

    Parkes, Stephen

    2015-04-01

    number of different in-situ analyzers that employ different optical methods. We compare this simplified calibration technique to more conventional characterization of both the cross-sensitivity determined in isotopic ratio space and the isotopic ratio span. Utilizing this simplified calibration approach with improved software control can lead to a significant reduction in time spent calibrating in-situ instrumentation or enable an increase in calibration frequency as required to minimize measurement uncertainty.

  2. On the cross-sensitivity between water vapor mixing ratio and stable isotope measurements of in-situ analyzers

    KAUST Repository

    Parkes, Stephen; Wang,  Lixin; McCabe, Matthew

    2015-01-01

    number of different in-situ analyzers that employ different optical methods. We compare this simplified calibration technique to more conventional characterization of both the cross-sensitivity determined in isotopic ratio space and the isotopic ratio span. Utilizing this simplified calibration approach with improved software control can lead to a significant reduction in time spent calibrating in-situ instrumentation or enable an increase in calibration frequency as required to minimize measurement uncertainty.

  3. Applications of lead isotope rations for identification and apportionment on pollution sources in food

    International Nuclear Information System (INIS)

    Zhao Duoyong; Wei Yimin; Guo Boli; Wei Shuai

    2011-01-01

    Lead is one of the toxic heavy metals which can accumulate to an adverse effect level in human bodies through ingestion, inhalation or other pathways. Because of the persistent lead contamination in farmland environment, large risk exists in the primary stage of 'from farm to table' chain. Environmental media such as soils, atmospheric aerosols were the possible lead sources of agro-food. To pinpoint the pollution sources exactly, cut off the contamination pathways in time, and reduce the risk of hazard, pollution sources tracing was very important. Lead isotope ratio combined with certain models is an effective method to discriminate correctly pollution sources and calculate the individual source contributions. In this review, to provide theoretical and technical reference for controlling lead pollution in environment and food, lead pollution sources in food, tracing principle and methods of lead isotope ratios, and its applications on vegetable, tea, wine, cereal and other food products were concerned. (authors)

  4. Investigating the origin of Pb pollution in a terrestrial soil­-plant-­snail food chain by means of Pb isotope ratios

    NARCIS (Netherlands)

    Notten, M.J.M.; Walraven, N.; Beets, C.J.; Vroon, P.Z.; Rozema, J.; Aerts, R.

    2008-01-01

    Lead isotope ratios were used to trace the origin of Pb in a soil-plant (Urtica dioica)-snail (Cepaea nemoralis) food chain in two polluted locations in the floodplains of the rivers Meuse and Rhine (Biesbosch National Park) and one reference location in the Netherlands. Lead isotope ratios and

  5. INAA, AAS, and lead isotope analysis of ancient lead anchors from the black SEA

    International Nuclear Information System (INIS)

    Kuleff, I.; Djingova, R.; Alexandrova, A.

    1995-01-01

    Lead stock of wooden-lead anchors found along the Bulgarian Black Sea coast and typo logically dated VI c. B.C. - III c. A.D. have been analyzed for chemical composition and lead isotope ratios by INAA, AAS and mass spectrometry. Using multivariate methods for analysis as well as simple bi variate plots the lead for production of the stocks was localized as originating from Laurion, Thassos, Troas, Chalkidike and the Rhodopes. In general, the chemical composition is not recommended to be used for provenance study of lead artefacts. Combining the results from this study with the existing typo logical classification certain conclusion about the production and distribution of lead anchors in the Aegean region are made. (author). 22 refs., 3 figs., 4 tabs

  6. Tracing fetal and childhood exposure to lead using isotope analysis of deciduous teeth

    International Nuclear Information System (INIS)

    Shepherd, Thomas J.; Dirks, Wendy; Roberts, Nick M.W.; Patel, Jaiminkumar G.; Hodgson, Susan; Pless-Mulloli, Tanja; Walton, Pamela; Parrish, Randall R.

    2016-01-01

    We report progress in using the isotopic composition and concentration of Pb in the dentine and enamel of deciduous teeth to provide a high resolution time frame of exposure to Pb during fetal development and early childhood. Isotope measurements (total Pb and 208 Pb/ 206 Pb, 207 Pb/ 206 Pb ratios) were acquired by laser ablation inductively coupled mass spectrometry at contiguous 100 micron intervals across thin sections of the teeth; from the outer enamel surface to the pulp cavity. Teeth samples (n=10) were selected from two cohorts of children, aged 5–8 years, living in NE England. By integrating the isotope data with histological analysis of the teeth, using the daily incremental lines in dentine, we were able to assign true estimated ages to each ablation point (first 2–3 years for molars, first 1–2 years for incisors+pre-natal growth). Significant differences were observed in the isotope composition and concentration of Pb between children, reflecting differences in the timing and sources of exposure during early childhood. Those born in 2000, after the withdrawal of leaded petrol in 1999, have the lowest dentine Pb levels (<0.2 µg Pb/g) with 208 Pb/ 206 Pb (mean ±2σ: 2.126–2.079) 208 Pb/ 206 Pb (mean ±2σ: 0.879–0.856) ratios that correlate very closely with modern day Western European industrial aerosols (PM 10 , PM 2.5 ) suggesting that diffuse airborne pollution was probably the primary source and exposure pathway. Legacy lead, if present, is insignificant. For those born in 1997, dentine lead levels are typically higher (>0.4 µgPb/g) with 208 Pb/ 206 Pb (mean ±2σ: 2.145–2.117) 208 Pb/ 206 Pb (mean ±2σ: 0.898–0.882) ratios that can be modelled as a binary mix between industrial aerosols and leaded petrol emissions. Short duration, high intensity exposure events (1–2 months) were readily identified, together with evidence that dentine provides a good proxy for childhood changes in the isotope composition of blood Pb. Our pilot

  7. Petrol with isotopically differentiated lead added

    International Nuclear Information System (INIS)

    Magi, F.; Facchetti, S.; Garibaldi, P.

    1975-01-01

    An experiment is proposed aimed at determining the role of motor traffic in the pollution of the environment by lead, in particular of air, soil, vegetation, food and the human body. The technique of determining the isotopic composition of lead, used in the right way, should enable the whole problem to be solved. It is intended to add lead with a constant isotopic composition different from that of normally occuring lead, whether natural in origin or otherwise, to petrol in at least two regions of Italy. Analyses of lead samples taken from the principal mines have shown that Australian lead (Broken Hill Mine) has quite a different isotopic composition. This lead will therefore be used to prepare the antiknock additives for petrol sold in the regions in question. Adequate sampling should make it possible to determine the contribution to pollution of lead from motor vehicle exhausts. The regions chosen for the experiment are Piedmont (city and province of Turin) and Sardinia (city and province of Cagliari) - the first because of its high traffic density and level of industrialization, the second because of its remoteness and the lead content of the soil, which may affect food. Both regions present favourable conditions for supplying petrol of the intended type. The experiment is intended to last three years; the petrol with Australian lead will be marketed for a period of 18 months. The first results of analyses of the isotopic composition of lead contained in atmospheric dust in the city of Turin and of lead from a number of blood samples are reported in the paper

  8. Ancient bronze coins from Mediterranean basin: LAMQS potentiality for lead isotopes comparative analysis with former mineral

    Energy Technology Data Exchange (ETDEWEB)

    Torrisi, L., E-mail: Lorenzo.Torrisi@unime.it [Department of Physics Science - MIFT, Messina University, V.le F.S. d’Alcontres 31, 98166 S. Agata, Messina (Italy); Italiano, A. [INFN, Sezione di Catania, Gruppo collegato di Messina (Italy); Torrisi, A. [Institute of Optoelectronics, Military University of Technology, 2 Kaliskiego Str., 00-908 Warsaw (Poland)

    2016-11-30

    Highlights: • Surface and bulk compositional elements in ancient bronze coins were investigated using XRF analysis. • Lead stable isotope {sup 204}Pb, {sup 206}Pb, {sup 207}Pb and {sup 208}Pb were measured in ancient coins with LAMQS analysis. • Lead ratios {sup 208}Pb/{sup 206}Pb and {sup 207}Pb/{sup 206}Pb, measured by LAMQS, were compared with Brettscaife.net geological database relative to the minerals in different mines of Mediterranean basin. • Bronze coins were correlated to possible ancient mining sites of minerals from which lead was extracted. - Abstract: Bronze coins coming from the area of the Mediterranean basin, dated back the II–X Cent. A.D., were analyzed using different physical analytical techniques. Characteristic X-ray fluorescence was used with electrons and photons, in order to investigate the elemental composition of both the surface layers and bulk. Moreover, the quadrupole mass spectrometry coupled to laser ablation (LAMQS technique) in high vacuum was used to analyse typical material compounds from surface contamination. Mass spectrometry, at high resolution and sensitivity, extended up to 300 amu, allowed measuring the {sup 208}Pb/{sup 206}Pb and {sup 207}Pb/{sup 206}Pb isotopic ratios into the coins. Quantitative relative analyses of these isotopic ratios identify the coin composition such as a “fingerprint” depending on the mineral used to extract the lead. Isotopic ratios in coins can be compared to those of the possible minerals used to produce the bronze alloy. A comparison between the measured isotope ratios in the analyzed coins and the literature database, related to the mineral containing Pb as a function of its geological and geophysical extraction mine, is presented. The analysis, restricted to old coins and the mines of the Mediterranean basin, indicates a possible correlation between the coin compositions and the possible geological sites of the extracted mineral.

  9. Determination of trace element concentrations and stable lead, uranium and thorium isotope ratios by quadrupole-ICP-MS in NORM and NORM-polluted sample leachates

    Energy Technology Data Exchange (ETDEWEB)

    Mas, J.L., E-mail: ppmasb@us.es [Dpto. Fisica Aplicada I, EPS, Universidad de Sevilla, 41012 Sevilla (Spain); Villa, M. [Servicio de Radioisotopos, Centro de Investigacion, Tecnologia e Innovacion (CITIUS), Universidad de Sevilla, Avda. Reina Mercedes 4b, 41012 Sevilla (Spain); Dpto. Fisica Aplicada II, ETS de Arquitectura, Universidad de Sevilla, Avda. Reina Mercedes 2, 41012 Sevilla (Spain); Hurtado, S. [Servicio de Radioisotopos, Centro de Investigacion, Tecnologia e Innovacion (CITIUS), Universidad de Sevilla, Avda. Reina Mercedes 4b, 41012 Sevilla (Spain); Garcia-Tenorio, R. [Dpto. Fisica Aplicada II, ETS de Arquitectura, Universidad de Sevilla, Avda. Reina Mercedes 2, 41012 Sevilla (Spain)

    2012-02-29

    Highlights: Black-Right-Pointing-Pointer Polluted sediment and NORM samples. Black-Right-Pointing-Pointer An efficient yet fast process allowing multi-parametric determinations in <3 days. Black-Right-Pointing-Pointer Trace element concentrations, Pb, Th and U isotope ratios with a single instrument. - Abstract: This work focuses on the monitoring of the potential pollution in scenarios that involve NORM-related industrial activities (environmental or in-door scenarios). The objective was to develop a method to determine extent and origin of the contamination, suitable for monitoring (i.e. simple, fast and economical) and avoiding the use of too many different instruments. It is presented a radiochemical method that allows the determination of trace element concentrations and {sup 206}Pb/{sup 207}Pb/{sup 208}Pb, {sup 238}U/{sup 234}U and {sup 232}Th/{sup 230}Th isotope ratios using a single sample aliquot and a single instrument (ICP-QMS). Eichrom UTEVA{sup Registered-Sign} extraction chromatography minicolumns were used to separate uranium and thorium in sample leachates. Independent ICP-MS determinations of uranium and thorium isotope ratios were carried out afterwards. Previously a small aliquot of the leachate was used for the determination of trace element concentrations and lead isotope ratios. Several radiochemical arrangements were tested to get maximum performances and simplicity of the method. The performances of the method were studied in terms of chemical yields of uranium and thorium and removal of the potentially interfering elements. The established method was applied to samples from a chemical industry and sediments collected in a NORM-polluted scenario. The results obtained from our method allowed us to infer not only the extent, but also the sources of the contamination in the area.

  10. Deformation properties of lead isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Tolokonnikov, S. V.; Borzov, I. N.; Lutostansky, Yu. S.; Saperstein, E. E., E-mail: saper43-7@mail.ru [National Research Center Kurchatov Institute (Russian Federation)

    2016-01-15

    The deformation properties of a long lead isotopic chain up to the neutron drip line are analyzed on the basis of the energy density functional (EDF) in the FaNDF{sup 0} Fayans form. The question of whether the ground state of neutron-deficient lead isotopes can have a stable deformation is studied in detail. The prediction of this deformation is contained in the results obtained on the basis of the HFB-17 and HFB-27 Skyrme EDF versions and reported on Internet. The present analysis reveals that this is at odds with experimental data on charge radii and magnetic moments of odd lead isotopes. The Fayans EDF version predicts a spherical ground state for all light lead isotopes, but some of them (for example, {sup 180}Pb and {sup 184}Pb) prove to be very soft—that is, close to the point of a phase transition to a deformed state. Also, the results obtained in our present study are compared with the predictions of some other Skyrme EDF versions, including SKM*, SLy4, SLy6, and UNE1. By and large, their predictions are closer to the results arising upon the application of the Fayans functional. For example, the SLy4 functional predicts, in just the same way as the FaNDF{sup 0} functional, a spherical shape for all nuclei of this region. The remaining three Skyrme EDF versions lead to a deformation of some light lead isotopes, but their number is substantially smaller than that in the case of the HFB-17 and HFB-27 functionals. Moreover, the respective deformation energy is substantially lower, which gives grounds to hope for the restoration of a spherical shape upon going beyond the mean-field approximation, which we use here. Also, the deformation properties of neutron-rich lead isotopes are studied up to the neutron drip line. Here, the results obtained with the FaNDF{sup 0} functional are compared with the predictions of the HFB-17, HFB-27, SKM*, and SLy4 Skyrme EDF versions. All of the EDF versions considered here predict the existence of a region where neutron

  11. Lead and stable Pb-isotope characteristics of tropical soils in north-eastern Brazil

    International Nuclear Information System (INIS)

    Schucknecht, Anne; Matschullat, Jörg; Reimann, Clemens

    2011-01-01

    Stable Pb-isotope ratios are widely used as tracers for Pb-sources in the environment. Recently, a few publications have challenged the predominating view of environmental applications of Pb-isotopes. Present applications of Pb-isotopic tracers in soils largely represent the northern hemisphere. This study focuses on tropical soils from Paraíba, north-eastern Brazil. Lead concentrations and Pb-isotopic signatures (both 7N HNO 3 ) were determined at 30 sites along a 327 km E–W-transect, from the Atlantic coast at João Pessoa to some kilometers west of Patos, to identify possible processes for the observed (and anticipated) distribution pattern. Thirty samples each of litter (ORG) and top mineral soil (TOP) were taken on pasture land at suitable distance from roads or other potential contamination sources. Lead-content was determined by inductively-coupled plasma atomic emission spectrometry (ICP-AES) and the ratios of 206 Pb/ 207 Pb, 206 Pb/ 208 Pb, and 208 Pb/ 207 Pb by ICP-sector field mass spectrometry (ICP-SFMS). Both sample materials show similarly low Pb-concentrations with a lower median in the ORG samples (ORG 3.4 mg kg −1 versus TOP 6.9 mg kg −1 ). The 206 Pb/ 207 Pb ratios revealed a large spread along the transect with median 206 Pb/ 207 Pb ratios of 1.160 (ORG) and 1.175 (TOP). The 206 Pb/ 207 Pb ratios differ noticeably between sample sites located in the Atlantic Forest biome along the coast and sample sites in the inland Caatinga biome. The “forest” sites were characterised by a significant lower median and a lower spread in the 206 Pb/ 207 Pb and 206 Pb/ 208 Pb ratios compared to the Caatinga sites. Results indicate a very restricted influence of anthropogenic activities (individual sites only). The main process influencing the spatial variability of Pb-isotope ratios is supposed to be precipitation-dependent bioproductivity and weathering.

  12. Study of the matrix specific mass discrimination effects during inductively coupled plasma mass spectrometry isotope ratio measurements

    International Nuclear Information System (INIS)

    Vassileva, E.; Quetel, Ch.R.

    2004-01-01

    Sample matrix related effects on mass discrimination during inductively coupled plasma mass spectrometry (ICP-MS) isotope ratio measurements have only been rarely reported. However, they can lead to errors larger than the uncertainty claimed on the ratio results when not properly taken into account or corrected for. These matrix specific affects were experienced during an Isotope Dilution Mass Spectrometry (IDMS) campaign we carried out for the certification of the Cd amount content in some food digest samples (7% acidity and salts content around 450μg g -1 ). Dilution was not possible for Cd only present at the low ng g -1 level. Up to 1% difference was observed on Cd isotope ratio results between measurements performed directly or after matrix separation. This was a significant difference considering that less than 1.5% relative combined uncertainty was eventually estimated for these IDMS measurements. Similar results could be obtained either way after the implementation of necessary corrections. The direct measurement approach associated to a correction for mass discrimination effects using the food digest sample itself (and the IUPAC table values as reference for the natural Cd isotopic composition) was preferred as it was the easiest. Consequently, the impact of matrix effects on mass discrimination during isotope ratio measurements with two types of ICP- MS (quadrupole and magnetic sector instruments) was studied for 4 elements (Li, Cu, Cd and Tl). Samples of varying salinity (up to 0.25%) and acidity (up to 7%) characteristics were prepared using isotopic certified reference materials of these elements. The long term and short-term stability, respectively reproducibility and repeatability, of the results, as well as the evolution of the difference to certified ratio values were monitored. As expected the 13 investigated isotopic ratios were all sensitive to variations in salt and acid concentrations. Our experiments also showed that simultaneous variation

  13. The calibration of the intramolecular nitrogen isotope distribution in nitrous oxide measured by isotope ratio mass spectrometry.

    Science.gov (United States)

    Westley, Marian B; Popp, Brian N; Rust, Terri M

    2007-01-01

    Two alternative approaches for the calibration of the intramolecular nitrogen isotope distribution in nitrous oxide using isotope ratio mass spectrometry have yielded a difference in the 15N site preference (defined as the difference between the delta15N of the central and end position nitrogen in NNO) of tropospheric N2O of almost 30 per thousand. One approach is based on adding small amounts of labeled 15N2O to the N2O reference gas and tracking the subsequent changes in m/z 30, 31, 44, 45 and 46, and this yields a 15N site preference of 46.3 +/- 1.4 per thousand for tropospheric N2O. The other involves the synthesis of N2O by thermal decomposition of isotopically characterized ammonium nitrate and yields a 15N site preference of 18.7 +/- 2.2 per thousand for tropospheric N2O. Both approaches neglect to fully account for isotope effects associated with the formation of NO+ fragment ions from the different isotopic species of N2O in the ion source of a mass spectrometer. These effects vary with conditions in the ion source and make it impossible to reproduce a calibration based on the addition of isotopically enriched N2O on mass spectrometers with different ion source configurations. These effects have a much smaller impact on the comparison of a laboratory reference gas with N2O synthesized from isotopically characterized ammonium nitrate. This second approach was successfully replicated and leads us to advocate the acceptance of the site preference value 18.7 +/- 2.2 per thousand for tropospheric N2O as the provisional community standard until further independent calibrations are developed and validated. We present a technique for evaluating the isotope effects associated with fragment ion formation and revised equations for converting ion signal ratios into isotopomer ratios. Copyright 2007 John Wiley & Sons, Ltd.

  14. Lead isotope profiling in dairy calves.

    Science.gov (United States)

    Buchweitz, John; McClure-Brinton, Kimberly; Zyskowski, Justin; Stensen, Lauren; Lehner, Andreas

    2015-03-01

    Lead (Pb) is a common cause of heavy metal poisonings in cattle. Sources of Pb on farms include crankcase oil, machinery grease, batteries, plumbing, and paint chips. Consequently, consumption of Pb from these sources may negatively impact animal health and Pb may be inadvertently introduced into the food supply. Therefore, the scope of poisoning incidents must be clearly assessed and sources of intoxication identified and strategies to mitigate exposure evaluated and implemented to prevent future exposures. Stable isotope analysis by inductively-coupled plasma mass spectrometry (ICP-MS) has proven itself of value in forensic investigations. We report on the extension of Pb stable isotope analysis to bovine tissues and profile comparisons with paint chips and soils collected from an affected dairy farm to elucidate the primary source. Pb occurs naturally as four stable isotopes: (204)Pb, (206)Pb, (207)Pb, and (208)Pb. Herein a case is reported to illustrate the use of (207)Pb/(206)Pb and (208)Pb/(206)Pb ratios to link environmental sources of exposure with tissues from a poisoned animal. Chemical Pb profiling provides a valuable tool for field investigative approaches to Pb poisoning in production agriculture and is applicable to subclinical exposures. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. LITERATURE SURVEY ON ISOTOPIC ABUNDANCE RATIO MEASUREMENTS - 2001-2005

    International Nuclear Information System (INIS)

    HOLDEN, N.E.

    2005-01-01

    Along with my usual weekly review of the published literature for new nuclear data, I also search for new candidates for best measurements of isotopic abundances from a single source. Most of the published articles, that I previously had found in the Research Library at the Brookhaven Lab, have already been sent to the members of the Atomic Weights Commission, by either Michael Berglund or Thomas Walczyk. In the last few days, I checked the published literature for any other articles in the areas of natural variations in isotopic abundance ratios, measurements of isotopic abundance ratios on samples of extra-terrestrial material and isotopic abundance ratio measurements performed using ICPMS instruments. Hopefully this information will be of interest to members of the Commission, the sub-committee on isotopic abundance measurements (SIAM), members of the former sub-committee on natural isotopic fractionation (SNIF), the sub-committee on extra-terrestrial isotope ratios (SETIR), the RTCE Task Group and the Guidelines Task Group, who are dealing with ICPMS and TIMS comparisons. In the following report, I categorize the publications in one of four areas. Measurements performed using either positive or negative ions with Thermal Ionization Mass Spectrometer, TIMS, instruments; measurements performed on Inductively Coupled Plasma Mass Spectrometer, ICPMS, instruments; measurements of natural variations of the isotopic abundance ratios; and finally measurements on extra-terrestrial samples with instrumentation of either type. There is overlap in these areas. I selected out variations and ET results first and then categorized the rest of the papers by TIMS and ICPMS

  16. Contaminated lead environments of man: reviewing the lead isotopic evidence in sediments, peat, and soils for the temporal and spatial patterns of atmospheric lead pollution in Sweden.

    Science.gov (United States)

    Bindler, Richard

    2011-08-01

    Clair Patterson and colleagues demonstrated already four decades ago that the lead cycle was greatly altered on a global scale by humans. Moreover, this change occurred long before the implementation of monitoring programs designed to study lead and other trace metals. Patterson and colleagues also developed stable lead isotope analyses as a tool to differentiate between natural and pollution-derived lead. Since then, stable isotope analyses of sediment, peat, herbaria collections, soils, and forest plants have given us new insights into lead biogeochemical cycling in space and time. Three important conclusions from our studies of lead in the Swedish environment conducted over the past 15 years, which are well supported by extensive results from elsewhere in Europe and in North America, are: (1) lead deposition rates at sites removed from major point sources during the twentieth century were about 1,000 times higher than natural background deposition rates a few thousand years ago (~10 mg Pb m(-2) year(-1) vs. 0.01 mg Pb m(-2) year(-1)), and even today (~1 mg Pb m(-2) year(-1)) are still almost 100 times greater than natural rates. This increase from natural background to maximum fluxes is similar to estimated changes in body burdens of lead from ancient times to the twentieth century. (2) Stable lead isotopes ((206)Pb/(207)Pb ratios shown in this paper) are an effective tool to distinguish anthropogenic lead from the natural lead present in sediments, peat, and soils for both the majority of sites receiving diffuse inputs from long range and regional sources and for sites in close proximity to point sources. In sediments >3,500 years and in the parent soil material of the C-horizon, (206)Pb/(207)Pb ratios are higher, 1.3 to >2.0, whereas pollution sources and surface soils and peat have lower ratios that have been in the range 1.14-1.18. (3) Using stable lead isotopes, we have estimated that in southern Sweden the cumulative anthropogenic burden of

  17. Calcium isotope ratios in animal and human bone

    Science.gov (United States)

    Reynard, L. M.; Henderson, G. M.; Hedges, R. E. M.

    2010-07-01

    Calcium isotopes in tissues are thought to be influenced by an individual's diet, reflecting parameters such as trophic level and dairy consumption, but this has not been carefully assessed. We report the calcium isotope ratios (δ 44/42Ca) of modern and archaeological animal and human bone ( n = 216). Modern sheep raised at the same location show 0.14 ± 0.08‰ higher δ 44/42Ca in females than in males, which we attribute to lactation by the ewes. In the archaeological bone samples the calcium isotope ratios of the herbivorous fauna vary by location. At a single site, the archaeological fauna do not show a trophic level effect. Humans have lower δ 44/42Ca than the mean site fauna by 0.22 ± 0.22‰, and the humans have a greater δ 44/42Ca range than the animals. No effect of sex or age on the calcium isotope ratios was found, and intra-individual skeletal δ 44/42Ca variability is negligible. We rule out dairy consumption as the main cause of the lower human δ 44/42Ca, based on results from sites pre-dating animal domestication and dairy availability, and suggest instead that individual physiology and calcium intake may be important in determining bone calcium isotope ratios.

  18. An update of the Pb isotope inventory in post leaded-petrol Singapore environments.

    Science.gov (United States)

    Carrasco, Gonzalo; Chen, Mengli; Boyle, Edward A; Tanzil, Jani; Zhou, Kuanbo; Goodkin, Nathalie F

    2018-02-01

    Pb is a trace metal that tracks anthropogenic pollution in natural environments. Despite recent leaded petrol phase out around Southeast Asia, the region's growth has resulted in continued exposure of Pb from a variety of sources. In this study, sources of Pb into Singapore, a highly urbanised city-state situated in the central axis of Southeast Asia, are investigated using isotopic ratios and concentrations. We compiled data from our previous analyses of aerosols, incineration fly ash and sediments, with new data from analyses of soil from gas stations, water from runoff and round-island coastal seawater to obtain a spatio-temporal overview of sources of Pb into the Singapore environment. Using 206 Pb/ 207 Pb ratio, we identified three main Pb source origins: natural Pb (1.215 ± 0.001), historic/remnant leaded petrol (1.123 ± 0.013), and present-day industrial and incinerated waste (1.148 ± 0.005). Deep reservoir sediments bore larger traces of Pb from leaded petrol, but present-day runoff waters and coastal seawater were a mix of industrial and natural sources with somewhat variable concentrations. We found temporal variability in Pb isotopic ratio in aerosols indicating alternating transboundary Pb sources to Singapore that correspond to seasonal changes in monsoon winds. By contrast, seasonal monsoon circulation did not significantly influence isotopic ratios of coastal seawater Pb. Instead, seawater Pb was driven more by location differences, suggesting stronger local-scale drivers of Pb such as point sources, water flushing, and isotope exchange. The combination of multiple historic and current sources of Pb shown in this study highlights the need for continued monitoring of Pb in Southeast Asia, especially in light of emerging industries and potential large sources of Pb such as coal combustion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. A study of radionuclides, metals and stable lead isotope ratios in sediments and soils in the vicinity of natural U-mineralisation areas in the Northern Territory

    International Nuclear Information System (INIS)

    Frostick, A.; Bollhoefer, A.; Parry, D.

    2011-01-01

    Australian guidelines recommend that tailings materials from uranium (U) mining and milling be contained without any detrimental impact on the environment for at least 1000 years. Natural analogue sites are being investigated to determine if they can provide data on the rates of natural erosion processes which occur over these timescales, for input into predictive geomorphic computer models. This paper presents radionuclide, metal and stable lead (Pb) isotope data from sediment cores and surface soils in the vicinity of two mineralised areas in the Alligator Rivers Region. Surface scrapes from the natural Anomaly no. 2, south of the Ranger mineral lease, exhibit radiogenic 206 Pb/ 207 Pb and 208 Pb/ 207 Pb ratios, and elevated U and metal concentrations typical for a near surface U anomaly. In contrast, samples taken from the Koongarra mineral lease (KML) show radionuclide activity and metal concentrations similar to natural areas elsewhere in the Alligator Rivers Region and Pb isotope ratios are closer to present day average crustal ratios (PDAC), as the orebodies at KML are covered by surficial sand. A sediment core collected from Anbangbang Billabong, downstream of KML, exhibits small variations in Pb isotope ratios that indicate that approximately 1% of the upper sediments in the sediment core may be derived from material originating from the U anomaly at Koongarra.

  20. A study of radionuclides, metals and stable lead isotope ratios in sediments and soils in the vicinity of natural U-mineralisation areas in the Northern Territory

    Energy Technology Data Exchange (ETDEWEB)

    Frostick, A., E-mail: Alison.Frostick@cdu.edu.au [Charles Darwin University, School of Environment and Life Sciences, Darwin NT 0909 (Australia); ERISS, GPO Box 461, Darwin NT 0801 (Australia); Bollhoefer, A. [ERISS, GPO Box 461, Darwin NT 0801 (Australia); Parry, D. [AIMS, PO Box 41775, Casuarina NT 0811 (Australia)

    2011-10-15

    Australian guidelines recommend that tailings materials from uranium (U) mining and milling be contained without any detrimental impact on the environment for at least 1000 years. Natural analogue sites are being investigated to determine if they can provide data on the rates of natural erosion processes which occur over these timescales, for input into predictive geomorphic computer models. This paper presents radionuclide, metal and stable lead (Pb) isotope data from sediment cores and surface soils in the vicinity of two mineralised areas in the Alligator Rivers Region. Surface scrapes from the natural Anomaly no. 2, south of the Ranger mineral lease, exhibit radiogenic {sup 206}Pb/{sup 207}Pb and {sup 208}Pb/{sup 207}Pb ratios, and elevated U and metal concentrations typical for a near surface U anomaly. In contrast, samples taken from the Koongarra mineral lease (KML) show radionuclide activity and metal concentrations similar to natural areas elsewhere in the Alligator Rivers Region and Pb isotope ratios are closer to present day average crustal ratios (PDAC), as the orebodies at KML are covered by surficial sand. A sediment core collected from Anbangbang Billabong, downstream of KML, exhibits small variations in Pb isotope ratios that indicate that approximately 1% of the upper sediments in the sediment core may be derived from material originating from the U anomaly at Koongarra.

  1. The measurement of the isotope ratios and concentrations of zinc by thermal ionization mass spectrometry using double isotope dilution

    International Nuclear Information System (INIS)

    Deng Zhongguo

    1994-01-01

    The isotope ratios and concentrations of zinc are measured by silicagel-thermal ionization mass spectrometry using the double isotope spikers. The double isotope spikers ( 70 Zn and 67 Zn-enriched isotopes) are used to correct the isotope mass fractionation for the zinc isotope ratios, and to certify the zinc concentrations in the unknown samples. The zinc concentrations of these double isotope spikers are surveyed by a spiker made of pure (99.99%) natural zinc metal powder. The correcting factors (f a , f t and f n ) of the zinc isotope ratios in the spiked mixture, spike and unspiked samples for the isotope mass fractionation, and the spike-to-unspiked ratios (X r ) of the zinc isotope r in the spiked mixture samples can be obtained to solve the matrix equations by numerical approximation. The natural zinc isotope ratios are: 64 Zn/ 67 Zn = 11.8498, 66 Zn/ 67 Zn = 6.7977, 68 Zn/ 67 Zn = 4.5730 and 70 Zn/ 67 Zn = 0.1520. The uncertainties determined of the isotope ratios and concentrations of zinc are +- 0.16% and +-0.31%, respectively

  2. Investigation of off-site airborne transport of lead from a superfund removal action site using lead isotope ratios and concentrations

    Science.gov (United States)

    Pribil, Michael J.; Maddaloni, Mark A.; Staiger, Kimberly; Wilson, Eric; Magriples, Nick; Ali, Mustafa; Santella, Dennis

    2014-01-01

    Lead (Pb) concentration and Pb isotopic composition of surface and subsurface soil samples were used to investigate the potential for off-site air transport of Pb from a former white Pb processing facility to neighboring residential homes in a six block area on Staten Island, NY. Surface and subsurface soil samples collected on the Jewett White Pb site were found to range from 1.122 to 1.138 for 206Pb/207Pb and 2.393 to 2.411 for 208Pb/207Pb. The off-site surface soil samples collected from residential backyards, train trestle, near site grass patches and background areas varied from 1.144 to 1.196 for 206Pb/207Pb and 2.427 to 2.464 for 208Pb/207Pb. Two soil samples collected along Richmond Terrace, where Jewett site soils accumulated after major rain events, varied from 1.136 to 1.147 for 206Pb/207Pb and 2.407 to 2.419 for 208Pb/207Pb. Lead concentration for on-site surface soil samples ranged from 450 to 8000 ug/g, on-site subsurface soil samples ranged from 90,000 to 240,000 ug/g and off-site samples varied from 380 to 3500 ug/g. Lead concentration and isotopic composition for the Staten Island off-site samples were similar to previously published data for other northeastern US cities and reflect re-suspension and re-mobilization of local accumulated Pb. The considerable differences in both the Pb isotopic composition and Pb concentration of on-site and off-site samples resulted in the ability to geochemically trace the transport of particulate Pb. Data in this study indicate minimal off-site surface transport of Pb from the Jewett site into the neighboring residential area.

  3. Isotope analytics for the evaluation of the feeding influence on the isotope ratio in beef samples; Isotopenanalytik zur Bestimmung des Einflusses der Ernaehrung auf die Isotopenzusammensetzung in Rinderproben

    Energy Technology Data Exchange (ETDEWEB)

    Herwig, Nadine

    2010-11-17

    Information about the origin of food and associated production systems has a high significance for food control. An extremely promising approach to obtain such information is the determination of isotope ratios of different elements. In this study the correlation of the isotope ratios C-13/C-12, N-15/N-14, Mg-25/Mg-24, and Sr-87/Sr-86 in bovine samples (milk and urine) and the corresponding isotope ratios in feed was investigated. It was shown that in the bovine samples all four isotope ratios correlate with the isotope composition of the feed. The isotope ratios of strontium and magnesium have the advantage that they directly reflect the isotope ratios of the ingested feed since there is no isotope fractionation in the bovine organism which is in contrast to the case of carbon and nitrogen isotope ratios. From the present feeding study it is evident, that a feed change leads to a significant change in the delta C-13 values in milk and urine within 10 days already. For the deltaN-15 values the feed change was only visible in the bovine urine after 49 days. Investigations of cows from two different regions (Berlin/Germany and Goestling/Austria) kept at different feeding regimes revealed no differences in the N-15/N-14 and Mg-26/Mg-24 isotope ratios. The strongest correlation between the isotope ratio of the bovine samples and the kind of ingested feed was observed for the carbon isotope ratio. With this ratio even smallest differences in the feed composition were traceable in the bovine samples. Since different regions usually coincide with different feeding regimes, carbon isotope ratios can be used to distinguish bovine samples from different regions if the delta C-13 values of the ingested feed are different. Furthermore, the determination of strontium isotope ratios revealed significant differences between bovine and feed samples of Berlin and Goestling due to the different geologic realities. Hence the carbon and strontium isotope ratios allow the best

  4. Isotope ratio monitoring LC/MS (IRM-LC/MS): new applications

    International Nuclear Information System (INIS)

    Juchelka, D; Hilkert, A.; Krummen, M.

    2005-01-01

    With the introduction of compound specific isotope analysis by isotope ratio monitoring GC/ MS (IRM-GC/MS) the immediate demand for similar applications using HPLC was created. Many compounds of biological, medical, pharmaceutical and environmental interest are not volatile or too polar. Consequently, they cannot be directly analyzed by gas chromatography. In IRM-GC/MS the carrier is helium, which does not interfere with the essential combust ion step prior to isotope ratio mass spectrometry (IRMS). In opposite the LC mobile phase has inhibited a similar direct conversion up to now. All earlier IRM-LC/MS approaches were based on the removal of the liquid phase prior to combustion risking fractionation of the isotope ratios of the eluted compounds. To avoid such restrictions we developed a new continuous flow concept for the coupling of an HPLC system to the isotope ratio MS for 13 C/ 12C isotope ratio analysis. In the Finnigan LC IsoLink, the liquid phase is not removed from the sample prior to oxidation. The sample is oxidized still in the mobile phase followed by on-line separation of the CO 2 from the liquid phase and transfer into the isotope ratio MS. Therefore, this strategy is based on water and inorganic buffers as mobile phase. The new approach opens up a whole new world in the application of gas isotope ratio mass spectrometry. The 13 C/ 12 C ratio s of organic acids, amino acids, carbohydrates and nucleotides can now be measured. These components typically within a complex matrix are separated by liquid chromatography followed by on-line determination of the isotope ratios. The draw backs of using derivatization and off-line preparation procedures can now be over come. This new technique allow s studying biochemical cycles, running tracer experiments and determining the origin of components. Applications from different scientific areas such as biogeochemistry, molecular biology, and pharmacy as well as authenticity control o f foods will be presented

  5. Tracing fetal and childhood exposure to lead using isotope analysis of deciduous teeth

    Energy Technology Data Exchange (ETDEWEB)

    Shepherd, Thomas J. [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne (United Kingdom); British Geological Survey, Keyworth, Nottingham (United Kingdom); Dirks, Wendy [Department of Anthropology, Durham University, Durham (United Kingdom); Roberts, Nick M.W. [NERC Isotope Geosciences Laboratory, British Geological Survey, Nottingham (United Kingdom); Patel, Jaiminkumar G. [Leeds Dental Institute, University Leeds, Leeds (United Kingdom); Hodgson, Susan [MRC-PHE Centre for Environment and Health, Department of Epidemiology and Biostatistics, Imperial College London (United Kingdom); Pless-Mulloli, Tanja [Institute of Health and Society, Newcastle University, Newcastle upon Tyne (United Kingdom); Walton, Pamela [Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne (United Kingdom); Parrish, Randall R. [British Geological Survey, Keyworth, Nottingham (United Kingdom)

    2016-04-15

    We report progress in using the isotopic composition and concentration of Pb in the dentine and enamel of deciduous teeth to provide a high resolution time frame of exposure to Pb during fetal development and early childhood. Isotope measurements (total Pb and {sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb ratios) were acquired by laser ablation inductively coupled mass spectrometry at contiguous 100 micron intervals across thin sections of the teeth; from the outer enamel surface to the pulp cavity. Teeth samples (n=10) were selected from two cohorts of children, aged 5–8 years, living in NE England. By integrating the isotope data with histological analysis of the teeth, using the daily incremental lines in dentine, we were able to assign true estimated ages to each ablation point (first 2–3 years for molars, first 1–2 years for incisors+pre-natal growth). Significant differences were observed in the isotope composition and concentration of Pb between children, reflecting differences in the timing and sources of exposure during early childhood. Those born in 2000, after the withdrawal of leaded petrol in 1999, have the lowest dentine Pb levels (<0.2 µg Pb/g) with {sup 208}Pb/{sup 206}Pb (mean ±2σ: 2.126–2.079) {sup 208}Pb/{sup 206}Pb (mean ±2σ: 0.879–0.856) ratios that correlate very closely with modern day Western European industrial aerosols (PM{sub 10}, PM{sub 2.5}) suggesting that diffuse airborne pollution was probably the primary source and exposure pathway. Legacy lead, if present, is insignificant. For those born in 1997, dentine lead levels are typically higher (>0.4 µgPb/g) with {sup 208}Pb/{sup 206}Pb (mean ±2σ: 2.145–2.117) {sup 208}Pb/{sup 206}Pb (mean ±2σ: 0.898–0.882) ratios that can be modelled as a binary mix between industrial aerosols and leaded petrol emissions. Short duration, high intensity exposure events (1–2 months) were readily identified, together with evidence that dentine provides a good proxy for childhood

  6. Stable lead isotopic analyses of historic and contemporary lead contamination of San Francisco Bay estuary

    Science.gov (United States)

    Ritson, P.I.; Bouse, R.M.; Flegal, A.R.; Luoma, S.N.

    1999-01-01

    Variations in stable lead isotopic composition (240Pb, 206Pb, 207Pb, 208Pb) in three sediment cores from the San Francisco Bay estuary document temporal changes in sources of lead during the past two centuries. Sediment, with lead from natural geologic sources, and relatively homogeneous lead isotopic compositions are overlain by sediments whose isotopic compositions indicate change in the sources of lead associated with anthropogenic modification of the estuary. The first perturbations of lead isotopic composition in the cores occur in the late 1800s concordant with the beginning of industrialization around the estuary. Large isotopic shifts, toward lower 206Pb/207Pb, occur after the turn of the century in both Richardson and San Pablo Bays. A similar relationship among lead isotopic compositions and lead concentrations in both Bays suggest contamination from the same source (a lead smelter). The uppermost sediments (post 1980) of all cores also have a relatively homogenous lead isotopic composition distinct from pre-anthropogenic and recent aerosol signatures. Lead isotopic compositions of leachates from fourteen surface sediments and five marsh samples from the estuary were also analyzed. These analyses suggest that the lead isotopic signature identified in the upper horizons of the cores is spatially homogeneous among recently deposited sediments throughout the estuary. Current aerosol lead isotopic compositions [Smith, D.R., Niemeyer, S., Flegal, A.R., 1992. Lead sources to California sea otters: industrial inputs circumvent natural lead biodepletion mechanisms. Environmental Research 57, 163-175] are distinct from the isotopic compositions of the surface sediments, suggesting that the major source of lead is cycling of historically contaminated sediments back through the water column. Both the upper core sediments and surface sediments apparently derive their lead predominantly from sources internal to the estuary. These results support the idea that

  7. MIR hollow waveguide (HWG) isotope ratio analyzer for environmental applications

    Science.gov (United States)

    Wang, Zhenyou; Zhuang, Yan; Deev, Andrei; Wu, Sheng

    2017-05-01

    An advanced commercial Mid-InfraRed Isotope Ratio (IR2) analyzer was developed in Arrow Grand Technologies based on hollow waveguide (HWG) as the sample tube. The stable carbon isotope ratio, i.e. δ13C, was obtained by measuring the selected CO2 absorption peaks in the MIR. Combined with a GC and a combustor, it has been successfully employed to measure compound specific δ13C isotope ratios in the field. By using both the 1- pass HWG and 5-path HWG, we are able to measure δ13C isotope ratio at a broad CO2 concentration of 300 ppm-37,500 ppm. Here, we demonstrate its applications in environmental studies. The δ13C isotope ratio and concentration of CO2 exhaled by soil samples was measured in real time with the isotope analyzer. The concentration was found to change with the time. We also convert the Dissolved Inorganic Carbon (DIC) into CO2, and then measure the δ13C isotope ratio with an accuracy of better than 0.3 ‰ (1 σ) with a 6 min test time and 1 ml sample usage. Tap water, NaHCO3 solvent, coca, and even beer were tested. Lastly, the 13C isotope ratio of CO2 exhaled by human beings was obtained <10 seconds after simply blowing the exhaled CO2 into a tube with an accuracy of 0.5‰ (1 σ) without sample preconditioning. In summary, a commercial HWG isotope analyzer was demonstrated to be able to perform environmental and health studies with a high accuracy ( 0.3 ‰/Hz1/2 1 σ), fast sampling rate (up to 10 Hz), low sample consumption ( 1 ml), and broad CO2 concentration range (300 ppm-37,500 ppm).

  8. Tracking historical lead pollution in the coastal area adjacent to the Yangtze River Estuary using lead isotopic compositions

    International Nuclear Information System (INIS)

    Hao Yunchao; Guo Zhigang; Yang Zuosheng; Fan, Dejiang; Fang Ming; Li Xiangdong

    2008-01-01

    The rapid economic development in the Yangtze River Delta (YRD), China in the last three decades has had a significant impact on the environment of the East China Sea (ECS). Lead isotopic compositions of a 210 Pb dated sediment core collected from the coastal ECS adjacent to the Yangtze River Estuary were analyzed to track the Pb pollution in the region. The baseline Pb concentration in the coastal ECS sediments before the industrialization in China was 32 μg g -1 , and the corresponding 206 Pb/ 207 Pb ratio was 1.195. The high-resolution profiles of Pb flux and 206 Pb/ 207 Pb ratios had close relationships with the economic development and the history of the use of leaded gasoline in China, and they were clearly different from those of most European countries and United States. - The combination of Pb concentration, sedimentary flux, Pb isotopic composition and 210 Pb dating in the coastal ECS sediments revealed the historical Pb pollution in China

  9. Lead in prehistoric, historic and contemporary Japanese: stable isotopic study by ICP mass spectrometry

    International Nuclear Information System (INIS)

    Suzuki, T.; Morita, M.; Yoneda, M.; Yoshinaga, J.

    1998-01-01

    Lead concentration and isotopic composition of prehistoric (middle and latest Jomon era, 2000-4500 BP, n=6), historic (Edo era, 130-400 BP, n=10), and contemporary (died in 1987-88, n=15) Japanese bones, and deciduous teeth from contemporary Japanese children born during 1985-88 (n=17) were analyzed by inductively coupled plasma mass spectrometry. Lead concentration was lowest in Jomon bones and was higher in rural Edo, contemporary, and urban Edo, in that order. Elevated Pb concentration in historic Edo people, as reported previously, was reconfirmed. The average isotopic ratios ( 207 Pb/ 206 Pb and 208 Pb/ 206 Pb) in excavated (prehistoric and historic) bones, contemporary bones, and deciduous teeth were different from each other. The contemporary bones had the least radiogenic composition (mean 207 Pb/ 206 Pb: 0.879; mean 208 Pb/ 206 Pb: 2.126) while the excavated bones the most (0.848; 2.098), and teeth intermediate (0.866; 2.111). The comparison with the literature data of isotopic compositions of environmental samples showed that the isotopic composition of the excavated bones was within the range of Japanese ores, rocks and soils, indicating the absence of foreign Pb sources in preindustrialized Japan. That of the contemporary bones was closer to the average gasoline Pb, the use of which had been banned in the late 1970s, than to the Pb in airborne particulate matter or refuse incineration ash of 1980s. The average Pb isotopic ratios in the deciduous teeth was close to the isotopic ratios of Pb in airborne particulate matter and refuse incineration ash. These data indicated that the contemporary Japanese population was exposed to foreign Pb which had different isotopic composition from domestic Pb. Exposure to Pb of foreign origin was particularly evidently recorded in people born before the leaded gasoline ban. The history of human Pb contamination in Japan is discussed based on the present results and other previously published data. (Copyright (c) 1998

  10. Development and application of liquid chromatography coupled to isotope ratio mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Lijun

    2014-02-19

    evaluated for, isotope ratio mass spectrometry (HT-RPLC/IRMS). The effect of column bleed on measured isotope ratios was investigated at high temperature in isothermal mode and in temperature gradient mode. Four different revised-phase columns were proven to be compatible with IRMS for compound-specific isotope analysis. The developed method was applied to measure caffeine in different drinks. Naturally occurring and industrially synthesized caffeine was observed to have two distinct δ{sup 13}C-ranges, from -25 to -32% circle and from -33 to -38% circle, respectively. On the basis of two different δ{sup 13}C-ranges, four out of 38 drinks were suspected of being mislabelled due to added but non-labelled synthetic caffeine with δ{sup 13}C-values falling in the range of synthetic caffeine. Furthermore, HTLC/IRMS was applied to measure non-polar and water-insoluble compounds, here steroids, for the first time. The use of steroid isotope analysis for pharmaceutical product control by HTLC/IRMS was demonstrated. The major advantage is that steroids can be analysed without derivatization. By overcoming current limitations in sample preparation, the method might become applicable for doping control purposes. Another potential application of LC/IRMS in doping control is the isotope analysis of 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR), a gene doping drug. Here, the first method for compound-specific isotope analysis of AICAR has been presented. The endogenous AICAR in urine and industrially synthesized AICAR were observed to have significantly different isotope signature. It shows that isotope analysis of LC/IRMS could potentially be used for the detection of AICAR abuse. The methodological developments presented in the thesis will lead to new applications of LC/IRMS.

  11. Development and application of liquid chromatography coupled to isotope ratio mass spectrometry

    International Nuclear Information System (INIS)

    Zhang, Lijun

    2014-01-01

    evaluated for, isotope ratio mass spectrometry (HT-RPLC/IRMS). The effect of column bleed on measured isotope ratios was investigated at high temperature in isothermal mode and in temperature gradient mode. Four different revised-phase columns were proven to be compatible with IRMS for compound-specific isotope analysis. The developed method was applied to measure caffeine in different drinks. Naturally occurring and industrially synthesized caffeine was observed to have two distinct δ 13 C-ranges, from -25 to -32% circle and from -33 to -38% circle, respectively. On the basis of two different δ 13 C-ranges, four out of 38 drinks were suspected of being mislabelled due to added but non-labelled synthetic caffeine with δ 13 C-values falling in the range of synthetic caffeine. Furthermore, HTLC/IRMS was applied to measure non-polar and water-insoluble compounds, here steroids, for the first time. The use of steroid isotope analysis for pharmaceutical product control by HTLC/IRMS was demonstrated. The major advantage is that steroids can be analysed without derivatization. By overcoming current limitations in sample preparation, the method might become applicable for doping control purposes. Another potential application of LC/IRMS in doping control is the isotope analysis of 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR), a gene doping drug. Here, the first method for compound-specific isotope analysis of AICAR has been presented. The endogenous AICAR in urine and industrially synthesized AICAR were observed to have significantly different isotope signature. It shows that isotope analysis of LC/IRMS could potentially be used for the detection of AICAR abuse. The methodological developments presented in the thesis will lead to new applications of LC/IRMS.

  12. Stable isotope ratio measurements in hydrogen, nitrogen, and oxygen using Raman scattering

    International Nuclear Information System (INIS)

    Harney, R.C.; Bloom, S.D.; Milanovich, F.P.

    1975-01-01

    A method for measuring stable isotope ratios using laser Raman scattering was developed which may prove of significant utility and benefit in stable isotope tracer studies. Crude isotope ratio measurements obtained with a low-power laser indicate that with current technology it should be possible to construct an isotope ratio measurement system using laser Raman scattering that is capable of performing 0.1 percent accuracy isotope ratio measurements of 16 O/ 18 O in natural abundance oxygen gas or 14 N/ 15 N in natural abundance nitrogen gas in times less than two minutes per sample. Theory pertinent to the technique, designs of specific isotope ratio spectrometer systems, and data relating to isotope ratio measurements in hydrogen, nitrogen, and oxygen are presented. In addition, the current status of several studies utilizing this technique is discussed. (auth)

  13. Tracing toxic elements sources using lead isotopes: An example from the San Antonio–El Triunfo mining district, Baja California Sur, México

    International Nuclear Information System (INIS)

    Gutiérrez-Caminero, Leopoldo; Weber, Bodo; Wurl, Jobst; Carrera-Muñoz, Mariela

    2015-01-01

    Highlights: • Provenance of toxic elements is investigated in a basin close to the mining district. • Stable lead isotope analyses assist to distinguish between sources of toxic elements. • Two major sources are identified: mine tailings and fault bounded mineralization. • There is evidence in the detritus of a different natural lead component. • An additional anthropogenic lead input is detectable from the soluble phases. - Abstract: Pollution of sediments and water bodies with toxic elements around the San Antonio–El Triunfo mining district, Baja California Sur, México is probably sourced from the tailings of abandoned mines that are hosted in mineralized Cretaceous granitoids. However, there is evidence to suggest local hot springs related to recent faults may be an additional source for contamination in the area. In this study, lead isotope signatures are applied to draw conclusions with regard to potential sources of toxic elements. Lead isotope ratios were analyzed from sulfides and scoria from the abandoned mines, fluvial sediments, and igneous rocks with secondary disseminated mineralization. To differentiate between superposed secondary and residual primary lead, leaching experiments were performed, and both leachate and residues were analyzed separately. Most of the residues from sediment samples have lead isotope ratios similar to those from the sulfides and scoria of the mining district, indicating that most of the lead in the detritus is related to the mineralized plutons. However, there is evidence of an additional detrital component. Lead isotope ratios from the leachates indicate a different source for the superimposed lead that is best explained by the contamination with the average Mexican industrial lead. Secondary disseminated mineralization that is related to younger, deep structures (hot springs) has different lead isotope ratios compared to massive vein sulfides and accounts for a significant amount in areas with high

  14. Successful application of lead isotopes in source apportionment, legal proceedings, remediation and monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Gulson, Brian, E-mail: brian.gulson@mq.edu.au [Graduate School of the Environment, Faculty of Science, Macquarie University, Sydney, NSW 2109 (Australia); CSIRO Earth Science and Resource Engineering North Ryde, NSW 1670 (Australia); Korsch, Michael [CSIRO Earth Science and Resource Engineering North Ryde, NSW 1670 (Australia); Winchester, Wayne; Devenish, Matthew; Hobbs, Thad [Esperance Cleanup and Recovery Project, Western Australia (WA) Department of Transport, Esperance 6450 (Australia); Main, Cleve; Smith, Gerard [Animal Health Laboratory, Department of Agriculture and Food, Perth 6151, WA (Australia); Rosman, Kevin; Howearth, Lynette; Burn-Nunes, Laurie [Curtin University, Department of Imaging and Applied Physics, Bentley 6102, WA (Australia); Seow, Jimmy; Oxford, Cameron [Department of Environment and Conservation, Booragoon 6154, WA (Australia); Yun, Gracie; Gillam, Lindsay [Department of Health, East Perth 6004, WA (Australia); Crisp, Michelle [LED (Locals for Esperance Development), Esperance 6450, WA (Australia)

    2012-01-15

    In late 2006, the seaside community in Esperance Western Australia was alerted to thousands of native bird species dying. The source of the lead (Pb) was determined by Pb isotopes to derive from the handling of Pb carbonate concentrate through the Port, which began in July 2005. Concern was expressed for the impact of this on the community. Our objectives were to employ Pb isotope ratios to evaluate the source of Pb in environmental samples for use in legal proceedings, and for use in remediation and monitoring. Isotope measurements were undertaken of bird livers, plants, drinking water, soil, harbour sediments, air, bulk ceiling dust, gutter sludge, surface swabs and blood. The unique lead isotopic signature of the contaminating Pb carbonate enabled diagnostic apportionment of lead in samples. Apart from some soil and water samples, the proportion of contaminating Pb was >95% in the environmental samples. Lead isotopes were critical in resolving legal proceedings, are being used in the remediation of premises, were used in monitoring of workers involved in the decontamination of the storage facility, and monitoring transport of the concentrate through another port facility. Air samples show the continued presence of contaminant Pb, more than one year after shipping of concentrate ceased, probably arising from dust resuspension. Brief details of the comprehensive testing and cleanup of the Esperance community are provided along with the role of the Community. Lead isotopic analyses can provide significant benefits to regulatory agencies, interested parties, and the community where the signature is able to be characterised with a high degree of certainty. - Highlights: Black-Right-Pointing-Triangle Lead carbonate concentrate. Black-Right-Pointing-Triangle Successful use of Pb isotopes in identifying sources of Pb arising from transport and shipping. Black-Right-Pointing-Triangle Use of Pb isotopes in legal proceedings and their use in cleanup of residences. Black

  15. Isotopic ratio method for determining uranium contamination

    International Nuclear Information System (INIS)

    Miles, R.E.; Sieben, A.K.

    1994-01-01

    The presence of high concentrations of uranium in the subsurface can be attributed either to contamination from uranium processing activities or to naturally occurring uranium. A mathematical method has been employed to evaluate the isotope ratios from subsurface soils at the Rocky Flats Nuclear Weapons Plant (RFP) and demonstrates conclusively that the soil contains uranium from a natural source and has not been contaminated with enriched uranium resulting from RFP releases. This paper describes the method used in this determination which has widespread application in site characterizations and can be adapted to other radioisotopes used in manufacturing industries. The determination of radioisotope source can lead to a reduction of the remediation effort

  16. Do Strontium Isotope Ratios of Animal Bone and Teeth Really Reflect the Isotope Ratios of its birth- and growth-places?

    Science.gov (United States)

    Minami, M.; Goto, A.; Suzuki, K.; Kato, T.; Watanabe, K.; Hasegawa, T.

    2007-12-01

    Strontium enters the human body through the food chain as nutrients pass from bedrock through soil and water to plants and animals. Strontium substitutes for calcium in the hydroxyapatite mineral of skeletal tissue, and is stored there. 87Sr/86Sr ratios in an individual's bone and teeth could directly reflect the isotopic ratios found in the plants and animals that she or he consumed, which reflect the isotope ratios found in the soil and bedrock of that geologic region. Therefore, 87Sr/86Sr ratios of human skeletons could be useful tools for assessing human residential mobility in prehistory, and many studies on them have been often made. In this study, to evaluate whether the 87Sr/86Sr ratio of a bone or teeth really reflects the isotopic ratios of its birth and growth places, several bone and teeth samples were measured for 87Sr/86Sr ratios, compared with 87Sr/86Sr ratios of geological samples in their growth-places. Bone and teeth samples were leached with 5% acetic acid. After drying, samples were ashed in a muffle furnace at 825°C for 8h, and then digested in nitric acid, followed by cation exchange chromatography with 2.4M hydrochloric acid. 87Sr/86Sr ratios were measured using a thermal ionization mass Spectrometer (VG Sector 54) or an inductively coupled plasma mass spectrometer (Finnigan ELEMENT2). A modern boar bone collected at Asuke, Toyota City, Aichi prefecture, Japan showed a 87Sr/86Sr of 0.71001±0.00002 (2 σ), while stream sediments in the Asuke area showed around 0.710 (Asahara et al., 2006). The 87Sr/86Sr ratio of a modern black bass bone collected from Lake Biwa, Shiga prefecture, Japan was 0.71215±0.00002, while those of surface water in Lake Biwa was 0.71233±0.00002. The similar 87Sr/86Sr ratios between bone and its provenance geology could indicate that the 87Sr/86Sr ratios of bones reflect the isotopic ratios of the birth- and growth-places. The more results of modern and fossil skeletons will be shown in our presentation.

  17. Sulphur and lead isotopes in strata-bound deposits, ch. 8

    International Nuclear Information System (INIS)

    Sangster, D.F.

    1976-01-01

    The use of sulphur and lead isotopes as isotopic tracers in the study of ore deposits containing these elements is reviewed. A discussion of the general theory, including abundance and fractionation of sulphur isotopes, single-stage leads, and anomalous leads (two-stage) is given. Attention is paid to sulphur isotopes enclosed in deposits which are located in marine host rocks and in rocks of continental or near-continental origin, as well as in deposits of the conglomerate-U(-Au) type. The lead isotope content of volcanogenic massive sulphide deposits and carbonate-hosted lead-zinc deposits is discussed

  18. Isotopic ratios in outbursting comet C/2015 ER61

    Science.gov (United States)

    Yang, Bin; Hutsemékers, Damien; Shinnaka, Yoshiharu; Opitom, Cyrielle; Manfroid, Jean; Jehin, Emmanuël; Meech, Karen J.; Hainaut, Olivier R.; Keane, Jacqueline V.; Gillon, Michaël

    2018-02-01

    Isotopic ratios in comets are critical to understanding the origin of cometary material and the physical and chemical conditions in the early solar nebula. Comet C/2015 ER61 (PANSTARRS) underwent an outburst with a total brightness increase of 2 magnitudes on the night of 2017 April 4. The sharp increase in brightness offered a rare opportunity to measure the isotopic ratios of the light elements in the coma of this comet. We obtained two high-resolution spectra of C/2015 ER61 with UVES/VLT on the nights of 2017 April 13 and 17. At the time of our observations, the comet was fading gradually following the outburst. We measured the nitrogen and carbon isotopic ratios from the CN violet (0, 0) band and found that 12C/13C = 100 ± 15, 14N/15N = 130 ± 15. In addition, we determined the 14N/15N ratio from four pairs of NH2 isotopolog lines and measured 14N/15N = 140 ± 28. The measured isotopic ratios of C/2015 ER61 do not deviate significantly from those of other comets.

  19. Steroid isotopic standards for gas chromatography-combustion isotope ratio mass spectrometry (GCC-IRMS).

    Science.gov (United States)

    Zhang, Ying; Tobias, Herbert J; Brenna, J Thomas

    2009-03-01

    Carbon isotope ratio (CIR) analysis of urinary steroids using gas chromatography-combustion isotope ratio mass spectrometry (GCC-IRMS) is a recognized test to detect illicit doping with synthetic testosterone. There are currently no universally used steroid isotopic standards (SIS). We adapted a protocol to prepare isotopically uniform steroids for use as a calibrant in GCC-IRMS that can be analyzed under the same conditions as used for steroids extracted from urine. Two separate SIS containing a mixture of steroids were created and coded CU/USADA 33-1 and CU/USADA 34-1, containing acetates and native steroids, respectively. CU/USADA 33-1 contains 5alpha-androstan-3beta-ol acetate (5alpha-A-AC), 5alpha-androstan-3alpha-ol-17-one acetate (androsterone acetate, A-AC), 5beta-androstan-3alpha-ol-11, 17-dione acetate (11-ketoetiocholanolone acetate, 11k-AC) and 5alpha-cholestane (Cne). CU/USADA 34-1 contains 5beta-androstan-3alpha-ol-17-one (etiocholanolone, E), 5alpha-androstan-3alpha-ol-17-one (androsterone, A), and 5beta-pregnane-3alpha, 20alpha-diol (5betaP). Each mixture was prepared and dispensed into a set of about 100 ampoules using a protocol carefully designed to minimize isotopic fractionation and contamination. A natural gas reference material, NIST RM 8559, traceable to the international standard Vienna PeeDee Belemnite (VPDB) was used to calibrate the SIS. Absolute delta(13)C(VPDB) and Deltadelta(13)C(VPDB) values from randomly selected ampoules from both SIS indicate uniformity of steroid isotopic composition within measurement reproducibility, SD(delta(13)C)<0.2 per thousand. This procedure for creation of isotopic steroid mixtures results in consistent standards with isotope ratios traceable to the relevant international reference material.

  20. Lead isotopic characterization of respirable urban aerosols and related sources, Santiago-Chile

    International Nuclear Information System (INIS)

    Diaz, M; Kawashita, K; Antinao, J.L

    2001-01-01

    Santiago de Chile is located in a poorly ventilated valley at 33 o 30' latitude south at an altitude of 550m. Local climate is semi-arid with mean annual rainfall below 350mm. The atmospheric particles constitute one of the main factors of urban air pollution in the city. Morphological characterization of airborne particles of Santiago done by Scanning Electron Microscopy showed the presence of three groups of particles: crystalline. spherical and agglomerate particles. The crystalline shapes originated in geologic sources have perfectly defined crystallographic parameters. The agglomerated shapes are formed by organic material and submicrometrical mineral particles derived from combustion of fossil fuel and the spherical shapes are products of metallurgical activities. Some of them could been associated with the wear of motorcars. Samples of aerosols. sediments and leaded petrol of different distributors were collected. Aerosols were sampled in two sites of Santiago: the Movil monitoring station, at east of the city, and Parque O'Higgins monitoring station in downtown. These two monitoring stations belong to the MACAM network. Sediments of Mapocho, Maipo, San Francisco and Zanjon de la Aguada rivers and two samples from Disputada and Merceditas ores were studied. All the samples have been measured for their 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb ratios. The experimental chemical procedures of sample dissolution and Pb separation by anion exchange chromatography were developed in the Sernageomin clean laboratory of Santiago de Chile. The isotopic measurements were made using a VG-Sector isotope ratio mass spectrometer fitted with a thermal ion source, multi Faraday collector and Daly collector of the Isotopic Geology Laboratory in the Universidade Federal de Rio Grande do Sul, Brazil. The measurements were corrected using NBS 981 and 982 standards. Isotopic results plotted in a 208 Pb/ 204 Pb versus 206 Pb/ 204 Pb diagram and in a 207 Pb/ 204 Pb versus

  1. MAGNESIUM ISOTOPE RATIOS IN ω CENTAURI RED GIANTS

    International Nuclear Information System (INIS)

    Da Costa, G. S.; Norris, John E.; Yong, David

    2013-01-01

    We have used the high-resolution observations obtained at the Anglo-Australian Telescope with Ultra-High Resolution Facility (R ∼ 100,000) and at Gemini-S with b-HROS (R ∼ 150,000) to determine magnesium isotope ratios for seven ω Cen red giants that cover a range in iron abundance from [Fe/H] = –1.78 to –0.78 dex, and for two red giants in M4 (NGC 6121). The ω Cen stars sample both the ''primordial'' (i.e., O-rich, Na- and Al-poor) and the ''extreme'' (O-depleted, Na- and Al-rich) populations in the cluster. The primordial population stars in both ω Cen and M4 show ( 25 Mg, 26 Mg)/ 24 Mg isotopic ratios that are consistent with those found for the primordial population in other globular clusters with similar [Fe/H] values. The isotopic ratios for the ω Cen extreme stars are also consistent with those for extreme population stars in other clusters. The results for the extreme population stars studied indicate that the 26 Mg/ 24 Mg ratio is highest at intermediate metallicities ([Fe/H] 26 Mg in the extreme population stars is notably higher than that of 25 Mg, in contrast to model predictions. The 25 Mg/ 24 Mg isotopic ratio in fact does not show any obvious dependence on either [Fe/H] or [Al/Fe] nor, intriguingly, any obvious difference between the primordial and extreme population stars.

  2. Determination of fission gas yields from isotope ratios

    DEFF Research Database (Denmark)

    Mogensen, Mogens Bjerg

    1983-01-01

    This paper describes a method of calculating the actual fission yield of Kr and Xe in nuclear fuel including the effect of neutron capture reactions and decay. The bases for this calculation are the cumulative yields (ref. 1) of Kr and Xe isotopes (or pairs of isotopes) which are unaffected...... by neutron capture reactions, and measured Kr and Xe isotope ratios. Also the burnup contribution from the different fissile heavy isotopes must be known in order to get accurate fission gas yields....

  3. An improved data acquisition system for isotopic ratio mass spectrometers

    International Nuclear Information System (INIS)

    Saha, T.K.; Reddy, B.; Nazare, C.K.; Handu, V.K.

    1999-01-01

    Isotopic ratio mass spectrometers designed and fabricated to measure the isotopic ratios with a precision of better than 0.05%. In order to achieve this precision, the measurement system consisting of ion signal to voltage converters, analog to digital converters, and data acquisition electronics should be at least one order better than the overall precision of measurement. Using state of the art components and techniques, a data acquisition system, which is an improved version of the earlier system, has been designed and developed for use with multi-collector isotopic ratio mass spectrometers

  4. Liquid and gas chromatography coupled to isotope ratio mass spectrometry for the determination of 13C-valine isotopic ratios in complex biological samples.

    Science.gov (United States)

    Godin, Jean-Philippe; Breuillé, Denis; Obled, Christiane; Papet, Isabelle; Schierbeek, Henk; Hopfgartner, Gérard; Fay, Laurent-Bernard

    2008-10-01

    On-line gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is commonly used to measure isotopic ratios at natural abundance as well as for tracer studies in nutritional and medical research. However, high-precision (13)C isotopic enrichment can also be measured by liquid chromatography-isotope ratio mass spectrometry (LC-IRMS). Indeed, LC-IRMS can be used, as shown by the new method reported here, to obtain a baseline separation and to measure (13)C isotopic enrichment of underivatised amino acids (Asp, Thr-Ser, Glu, Pro, Gly, Ala, Cys and Val). In case of Val, at natural abundance, the SD(delta(13)C) reported with this method was found to be below 1 per thousand . Another key feature of the new LC-IRMS method reported in this paper is the comparison of the LC-IRMS approach with the conventional GC-C-IRMS determination. To perform this comparative study, isotopic enrichments were measured from underivatised Val and its N(O, S)-ethoxycarbonyl ethyl ester derivative. Between 0.0 and 1.0 molar percent excess (MPE) (delta(13)C= -12.3 to 150.8 per thousand), the calculated root-mean-square (rms) of SD was 0.38 and 0.46 per thousand and the calculated rms of accuracy was 0.023 and 0.005 MPE, respectively, for GC-C-IRMS and LC-IRMS. Both systems measured accurately low isotopic enrichments (0.002 atom percent excess (APE)) with an SD (APE) of 0.0004. To correlate the relative (delta(13)C) and absolute (atom%, APE and MPE) isotopic enrichment of Val measured by the GC-C-IRMS and LC-IRMS devices, mathematical equations showing the slope and intercept of the curves were established and validated with experimental data between 0.0 to 2.3 MPE. Finally, both GC-C-IRMS and LC-IRMS instruments were also used to assess isotopic enrichment of protein-bound (13)C-Val in tibial epiphysis in a tracer study performed in rats. Isotopic enrichments measured by LC-IRMS and GC-C-IRMS were not statistically different (p>0.05). The results of this work indicate that

  5. Successful application of lead isotopes in source apportionment, legal proceedings, remediation and monitoring.

    Science.gov (United States)

    Gulson, Brian; Korsch, Michael; Winchester, Wayne; Devenish, Matthew; Hobbs, Thad; Main, Cleve; Smith, Gerard; Rosman, Kevin; Howearth, Lynette; Burn-Nunes, Laurie; Seow, Jimmy; Oxford, Cameron; Yun, Gracie; Gillam, Lindsay; Crisp, Michelle

    2012-01-01

    In late 2006, the seaside community in Esperance Western Australia was alerted to thousands of native bird species dying. The source of the lead (Pb) was determined by Pb isotopes to derive from the handling of Pb carbonate concentrate through the Port, which began in July 2005. Concern was expressed for the impact of this on the community. Our objectives were to employ Pb isotope ratios to evaluate the source of Pb in environmental samples for use in legal proceedings, and for use in remediation and monitoring. Isotope measurements were undertaken of bird livers, plants, drinking water, soil, harbour sediments, air, bulk ceiling dust, gutter sludge, surface swabs and blood. The unique lead isotopic signature of the contaminating Pb carbonate enabled diagnostic apportionment of lead in samples. Apart from some soil and water samples, the proportion of contaminating Pb was >95% in the environmental samples. Lead isotopes were critical in resolving legal proceedings, are being used in the remediation of premises, were used in monitoring of workers involved in the decontamination of the storage facility, and monitoring transport of the concentrate through another port facility. Air samples show the continued presence of contaminant Pb, more than one year after shipping of concentrate ceased, probably arising from dust resuspension. Brief details of the comprehensive testing and cleanup of the Esperance community are provided along with the role of the Community. Lead isotopic analyses can provide significant benefits to regulatory agencies, interested parties, and the community where the signature is able to be characterised with a high degree of certainty. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

  6. Post-Wisconsinan Chemical Weathering Rates and Trajectories From a 13,400-Year Sediment Core Record of Lead Isotopic Ratios in Maine

    Science.gov (United States)

    Perry, R. H.; Norton, S. A.; Koons, P. O.; Handley, M.

    2008-12-01

    Lead isotopic ratios recorded in a 5.3-m 13.4-ka 14C-dated lake sediment core from Sargent Mountain Pond, Maine (USA) are interpreted as an archive of post-glacial chemical weathering. Early weathering yielded highly radiogenic sediment from the preferential release of U and Th decay products (206Pb, 207Pb, and 208Pb) from accessory mineral phases in the catchment's predominantly-granitic till and bedrock relative to non-radiogenic 204Pb from the more abundant primary minerals. Values for 207Pb/206Pb in the sediment increased rapidly from 0.799 to 0.814 in the catchment's first 4,000 years of post-Wisconsinan weathering, and thereafter increased only slightly to just prior to the 19th century. Values for 208Pb/204Pb, 207Pb/204Pb, and 206Pb/204Pb decline over the same time-scale, as a result of decreasing radiogenic Pb being released from catchment weathering. Our results are consistent with: (1) the published interpretation of Pb isotopic variation in ferromanganese ocean crusts as a reflection of continental-scale glacial-interglacial chemical weathering cycles, (2) bench-scale whole-rock weathering experiments, and (3) soil chronosequence Pb isotope dissolution experiments and bridge the gap between short-term, mineral-scale experiments and long-term, ocean sediment records. We establish a time-scale for depletion of accessory minerals, and loss of their Pb isotopic signature at one catchment, and document the concurrent shift to slower primary mineral-controlled chemical weathering after deglaciation.

  7. Lead isotopic fingerprinting of aerosols to characterize the sources of atmospheric lead in an industrial city of India

    Science.gov (United States)

    Sen, Indra S.; Bizimis, Michael; Tripathi, Sachchida Nand; Paul, Debajyoti

    2016-03-01

    Anthropogenic Pb in the environment is primarily sourced from combustion of fossil fuel and high-temperature industries such as smelters. Identifying the sources and pathways of anthropogenic Pb in the environment is important because Pb toxicity is known to have adverse effects on human health. Pb pollution sources for America, Europe, and China are well documented. However, sources of atmospheric Pb are unknown in India, particularly after leaded gasoline was phased out in 2000. India has a developing economy with a rapidly emerging automobile and high temperature industry, and anthropogenic Pb emission is expected to rise in the next decade. In this study, we report on the Pb-isotope compositions and trace metal ratios of airborne particulates collected in Kanpur, a large city in northern part of India. The study shows that the PM10 aerosols had elevated concentration of Cd, Pb, Zn, As, and Cu in the Kanpur area, however their concentrations are well below the United States Environmental Protection Agency chronic exposure limit. Lead isotopic and trace metal data reveal industrial emission as the plausible source of anthropogenic Pb in the atmosphere in Kanpur. However, Pb isotopic compositions of potential source end-members are required to fully evaluate Pb contamination in India over time. This is the first study that characterizes the isotopic composition of atmospheric Pb in an Indian city after leaded gasoline was phased out by 2000.

  8. Platinum stable isotope ratio measurements by double-spike multiple collector ICPMS

    DEFF Research Database (Denmark)

    Creech, John; Baker, Joel; Handler, Monica

    2013-01-01

    We present a new technique for the precise determination of platinum (Pt) stable isotope ratios by multiple-collector inductively coupled plasma mass spectrometry (MC-ICPMS) using two different Pt double-spikes ( Pt-Pt and Pt-Pt). Results are expressed relative to the IRMM-010 Pt isotope standard......) can be obtained on Pt stable isotope ratios with either double-spike. Elemental doping tests reveal that double-spike corrected Pt stable isotope ratios are insensitive to the presence of relatively high (up to 10%) levels of matrix elements, although the Pt-Pt double-spike is affected by an isobaric...... = 7.308%) results in a redefined Pt atomic weight of 195.08395 ± 0.00068. Using our technique we have measured small, reproducible and statistically significant offsets in Pt stable isotope ratios between different Pt element standards and the IRMM-010 standard, which potentially indicates...

  9. Determination of the geographic origin of rice by chemometrics with strontium and lead isotope ratios and multielement concentrations.

    Science.gov (United States)

    Ariyama, Kaoru; Shinozaki, Miyuki; Kawasaki, Akira

    2012-02-22

    The objective of this study was to develop a technique for determining the country of origin of rice in the Japanese market. The rice samples included a total of 350 products grown in Japan (n = 200), the United States (n = 50), China (n = 50), and Thailand (n = 50). In this study, (87)Sr/(86)Sr and Pb isotope ((204)Pb, (206)Pb, (207)Pb, and (208)Pb) ratios and multielement concentrations (Al, Fe, Co, Ni, Cu, Rb, Sr, and Ba) were determined by high-resolution inductively coupled plasma mass spectrometry. By combining three chemometric techniques based on different principles and determination criteria, the countries of origin of rice were determined. The predictions made by 10-fold cross-validation were around 97% accurate. The presented method demonstrated the effectiveness of determining the geographic origin of an agricultural product by combining several chemometric techniques using heavy element isotope ratios and multielement concentrations.

  10. The Pb isotopic record of historical to modern human lead exposure

    International Nuclear Information System (INIS)

    Kamenov, George D.; Gulson, Brian L.

    2014-01-01

    Human teeth and bones incorporate trace amounts of lead (Pb) from the local environment during growth and remodeling. Anthropogenic activities have caused changes in the natural Pb isotopic background since historical times and this is reflected in the Pb isotopes of historical European teeth. Lead mining and use increased exponentially during the last century and the isotopic compositions of modern human teeth reflect the modern anthropogenic Pb. USA teeth show the most radiogenic Pb and Australian teeth show the least radiogenic Pb, a result of different Pb ores used in the two regions. During the last century the Australian Pb was exported to Europe, Asia, South America, and Africa, resulting in swamping of the local environmental Pb signal by the imported Pb. As a result, the modern human teeth in Europe show a significant drop to lower isotopic values compared with historical times. Similarly, modern human teeth in other regions of the world show similar Pb isotopic ratios to modern European teeth reflecting the Pb imports. The specific pattern of human Pb exposure allows us to use the Pb isotopic signal recorded in the skeleton as a geo-referencing tool. As historical European teeth show a distinct Pb signal, we can identify early European skeletal remains in the New World and likely elsewhere. In modern forensic investigations we can discriminate to some extent Eastern Europeans from Western and Northern Europeans. Australians can be identified to some extent in any region in the world, although there is some overlap with Western European individuals. Lead isotopes can be used to easily identify foreigners in the USA, as modern USA teeth are distinct from any other region of the world. By analogy, USA individuals can be identified virtually in any other region of the world. - Highlights: • We present high-precision Pb isotope data for historical and modern human teeth. • Human teeth reflect human Pb exposure since historical times. • Modern teeth show

  11. The Pb isotopic record of historical to modern human lead exposure

    Energy Technology Data Exchange (ETDEWEB)

    Kamenov, George D., E-mail: kamenov@ufl.edu [Department of Geological Sciences, University of Florida, 241 Williamson Hall, Gainesville, FL 32611 (United States); Gulson, Brian L. [Graduate School of the Environment, Faculty of Science, Macquarie University, Sydney, NSW 2109 (Australia)

    2014-08-15

    Human teeth and bones incorporate trace amounts of lead (Pb) from the local environment during growth and remodeling. Anthropogenic activities have caused changes in the natural Pb isotopic background since historical times and this is reflected in the Pb isotopes of historical European teeth. Lead mining and use increased exponentially during the last century and the isotopic compositions of modern human teeth reflect the modern anthropogenic Pb. USA teeth show the most radiogenic Pb and Australian teeth show the least radiogenic Pb, a result of different Pb ores used in the two regions. During the last century the Australian Pb was exported to Europe, Asia, South America, and Africa, resulting in swamping of the local environmental Pb signal by the imported Pb. As a result, the modern human teeth in Europe show a significant drop to lower isotopic values compared with historical times. Similarly, modern human teeth in other regions of the world show similar Pb isotopic ratios to modern European teeth reflecting the Pb imports. The specific pattern of human Pb exposure allows us to use the Pb isotopic signal recorded in the skeleton as a geo-referencing tool. As historical European teeth show a distinct Pb signal, we can identify early European skeletal remains in the New World and likely elsewhere. In modern forensic investigations we can discriminate to some extent Eastern Europeans from Western and Northern Europeans. Australians can be identified to some extent in any region in the world, although there is some overlap with Western European individuals. Lead isotopes can be used to easily identify foreigners in the USA, as modern USA teeth are distinct from any other region of the world. By analogy, USA individuals can be identified virtually in any other region of the world. - Highlights: • We present high-precision Pb isotope data for historical and modern human teeth. • Human teeth reflect human Pb exposure since historical times. • Modern teeth show

  12. Lead concentration and isotope chronology in two coastal environments in Western and South East Asia

    Science.gov (United States)

    Carrasco, G. G.; Chen, M.; Boyle, E. A.; Zhao, N.; Nurhati, I. S.; Gevao, B.; al Ghadban, A.; Switzer, A.; Lee, J. M.

    2014-12-01

    Lead is a trace metal that is closely related to anthropogenic activity, mainly via leaded gasoline and coal combustion. The study of lead concentrations and isotopes in seawater, sediments, corals and aerosols allows for a systematic look at its sources and their time evolution in a natural environment. We will discuss results from two projects in Western and South East Asia, regions that have seen dramatic socio-economical changes over the past half-century that may have left environmental signals. These results highlight the usefulness of the method, indicate the degree of complexity of these systems, and point to the need for a continuous monitoring of anthropogenic trace metals in the small-medium coastal scale to be able to asses the larger scale effects of human activity. On the one hand, coastal Kuwait is heavily influenced by the Shat al-Arab river and shows a clear anthropogenic signature from Kuwait city. A mix of two sources can be tracked through the coral and sediment chronological records, with Pb206/Pb207 ratios (1.202 and 1.151) that approach the suspected source values (1.21 and 1.12) and eliminate the possibility of other sources. Through a wide sediment geographic distribution, the strength of the anthropogenic signature is modulated. On the other hand, Singapore offers a more complex system, where an apparent mix of two sources (extreme isotope ratios 1.215 and ~1.14) occurs also, but where either an unresolved potentially important third source (isotope ratio ~1.18), or an isotope exchange process should be invoked. The sediment and coral records allows us to track the changes through time; however, there seems to be incongruence with the aerosol isotope record. Further potential sources are being explored currently and will be discussed.

  13. Study by lead isotope method of a vein : Sobrado of the Boquira mine (Bahia State, Brazil)

    International Nuclear Information System (INIS)

    Cassedanne, J.P.; Duthou, J.-L.; Clermont-Ferrand Univ., 63

    1981-01-01

    Fourteen samples of galena from the Sobrado vein, Boquira mine (Bahia) are analysed. Lead isotope compositions show an irregular variation from the central part to the extremidades. They are the result of a mixture of lead from normal galenas and lead which aparent U/Pb ratio are higher. (ARHC) [pt

  14. Uranium isotope ratio measurements in field settings

    International Nuclear Information System (INIS)

    Shaw, R.W.; Barshick, C.M.; Young, J.P.; Ramsey, J.M.

    1997-01-01

    The authors have developed a technique for uranium isotope ratio measurements of powder samples in field settings. Such a method will be invaluable for environmental studies, radioactive waste operations, and decommissioning and decontamination operations. Immediate field data can help guide an ongoing sampling campaign. The measurement encompasses glow discharge sputtering from pressed sample hollow cathodes, high resolution laser spectroscopy using conveniently tunable diode lasers, and optogalvanic detection. At 10% 235 U enrichment and above, the measurement precision for 235 U/( 235 U+ 238 U) isotope ratios was ±3%; it declined to ±15% for 0.3% (i.e., depleted) samples. A prototype instrument was constructed and is described

  15. Study of lead isotopes for investigating the origin of endogenic deposits with special reference to some ore deposits from India

    International Nuclear Information System (INIS)

    Chernyshev, I.V.; Safonov, Yu. G.; Radhakrishna, B.P.; Vasudev, V.N.; Krishna Rao, B.; Deb, M.

    1980-01-01

    The isotope composition of leads from ore deposits in general reflects the age of ore mineralisation and its genetical features. Calculations of the model age from lead isotope data form the basis for genetic reconstructions of Precambrain deposits. Radical improvement in the accuracy of mass spectrometric isotope lead analysis has made possible the employment of two-stage and in some cases more complicated models for genetic reconstructions. Fifteen galena samples from five sulphide and gold-sulphide deposits of the Indian Shield have been selected and determination of lead isotope composition has been carried out in the USSR using recently developed M.I.1320 Mass Spectrometer. The isotopic ratios of galena from Ingaldhal copper deposit are the most primitive among the analysed ores of the Indian Shield. The results of lead isotopic determination have been interpreted in terms of the general theory of 'plumbotectonics'. (auth.)

  16. System and method for high precision isotope ratio destructive analysis

    Science.gov (United States)

    Bushaw, Bruce A; Anheier, Norman C; Phillips, Jon R

    2013-07-02

    A system and process are disclosed that provide high accuracy and high precision destructive analysis measurements for isotope ratio determination of relative isotope abundance distributions in liquids, solids, and particulate samples. The invention utilizes a collinear probe beam to interrogate a laser ablated plume. This invention provides enhanced single-shot detection sensitivity approaching the femtogram range, and isotope ratios that can be determined at approximately 1% or better precision and accuracy (relative standard deviation).

  17. Detection of counterfeit antiviral drug Heptodin and classification of counterfeits using isotope amount ratio measurements by multicollector inductively coupled plasma mass spectrometry (MC-ICPMS) and isotope ratio mass spectrometry (IRMS).

    Science.gov (United States)

    Santamaria-Fernandez, Rebeca; Hearn, Ruth; Wolff, Jean-Claude

    2009-06-01

    Isotope ratio mass spectrometry (IRMS) and multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) are highly important techniques that can provide forensic evidence that otherwise would not be available. MC-ICP-MS has proved to be a very powerful tool for measuring high precision and accuracy isotope amount ratios. In this work, the potential of combining isotope amount ratio measurements performed by MC-ICP-MS and IRMS for the detection of counterfeit pharmaceutical tablets has been investigated. An extensive study for the antiviral drug Heptodin has been performed for several isotopic ratios combining MC-ICP-MS and an elemental analyser EA-IRMS for stable isotope amount ratio measurements. The study has been carried out for 139 batches of the antiviral drug and analyses have been performed for C, S, N and Mg isotope ratios. Authenticity ranges have been obtained for each isotopic system and combined to generate a unique multi-isotopic pattern only present in the genuine tablets. Counterfeit tablets have then been identified as those tablets with an isotopic fingerprint outside the genuine isotopic range. The combination of those two techniques has therefore great potential for pharmaceutical counterfeit detection. A much greater power of discrimination is obtained when at least three isotopic systems are combined. The data from these studies could be presented as evidence in court and therefore methods need to be validated to support their credibility. It is also crucial to be able to produce uncertainty values associated to the isotope amount ratio measurements so that significant differences can be identified and the genuineness of a sample can be assessed.

  18. Isotopic ratios D/H and 15N/14N in giant planets

    Science.gov (United States)

    Marboeuf, Ulysse; Thiabaud, Amaury; Alibert, Yann; Benz, Willy

    2018-04-01

    The determination of isotopic ratios in planets is important since it allows us to investigate the origins and initial composition of materials. The present work aims to determine the possible range of values for isotopic ratios D/H and 15N/14N in giant planets. The main objective is to provide valuable theoretical assumptions on the isotopic composition of giant planets, their internal structure, and the main reservoirs of species. We use models of ice formation and planet formation that compute the composition of ices and gas accreted in the core and the envelope of planets. Assuming a single initial value for isotopic ratios in volatile species, and disruption of planetesimals in the envelope of gaseous planets, we obtain a wide variety of D/H and 15N/14N ratios in low-mass planets (≤100 Mearth) due to the migration pathway of planets, the accretion time of gas species whose relative abundance evolves with time, and isotope exchanges among species. If giant planets with mass greater than 100 Mearth have solar isotopic ratios such as Jupiter and Saturn due to their higher envelope mass, Neptune-type planets present values ranging between one and three times the solar value. It seems therefore difficult to use isotopic ratios in the envelope of these planets to get information about their formation in the disc. For giant planets, the ratios allow us to constrain the mass fraction of volatile species in the envelope needed to reproduce the observational data by assuming initial values for isotopic ratios in volatile species.

  19. Results of Am isotopic ratio analysis in irradiated MOX fuels

    Energy Technology Data Exchange (ETDEWEB)

    Koyama, Shin-ichi; Osaka, Masahiko; Mitsugashira, Toshiaki; Konno, Koichi [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center; Kajitani, Mikio

    1997-04-01

    For analysis of a small quantity of americium, it is necessary to separate from curium which has similar chemical property. As a chemical separation method for americium and curium, the oxidation of americium with pentavalent bismuth and subsequent co-precipitation of trivalent curium with BIP O{sub 4} were applied to analyze americium in irradiated MOX fuels which contained about 30wt% plutonium and 0.9wt% {sup 241}Am before irradiation and were irradiated up to 26.2GWd/t in the experimental fast reactor Joyo. The purpose of this study is to measure isotopic ratio of americium and to evaluate the change of isotopic ratio with irradiation. Following results are obtained in this study. (1) The isotopic ratio of americium ({sup 241}Am, {sup 242m}Am and {sup 243}Am) can be analyzed in the MOX fuels by isolating americium. The isotopic ratio of {sup 242m}Am and {sup 243}Am increases up to 0.62at% and 0.82at% at maximum burnup, respectively, (2) The results of isotopic analysis indicates that the contents of {sup 241}Am decreases, whereas {sup 242m}Am, {sup 243}Am increase linearly with increasing burnup. (author)

  20. Stable lead isotope compositions in selected coals from around the world and implications for present day aerosol source tracing

    Energy Technology Data Exchange (ETDEWEB)

    M. Diaz-Somoano; M.E. Kylander; M.A. Lopez-Anton; I. Suarez-Ruiz; M.R. Martinez-Tarazona; M. Ferrat; B. Kober; D.J. Weiss [Instituto Nacional del Carbon (INCAR-CSIC), Oviedo (Spain)

    2009-02-15

    The phasing out of leaded gasoline in many countries around the world at the end of the last millennium has resulted in a complex mixture of lead sources in the atmosphere. Recent studies suggest that coal combustion has become an important source of Pb in aerosols in urban and remote areas. Lead concentration and isotopic composition is reported for 59 coal samples representing major coal deposits worldwide in an attempt to characterize this potential source. The average concentration in these coals is 35 {mu}g Pb g{sup -1}, with the highest values in coals from Spain and Peru and the lowest in coals from Australia and North America. The {sup 206}Pb/{sup 207}Pb isotope ratios range between 1.15 and 1.24, with less radiogenic Pb in coals from Europe and Asia compared to South and North America. Comparing the Pb isotopic signatures of coals from this and previous studies with those published for Northern and Southern Hemisphere aerosols, we hypothesize that coal combustion might now be an important Pb source in China, the eastern U.S., and to some extent, in Europe but not as yet in other regions including South Africa, South America, and western U.S. This supports the notion that 'old Pb pollution' from leaded gasoline reemitted into the atmosphere or long-range transport (i.e., from China to the western U.S.) is important. Comparing the isotope ratios of the coals, the age of the deposits, and Pb isotope evolution models for the major geochemical reservoirs suggests that the lead isotope ratios (PbIC) in coals is strongly influenced by the depositional coal forming environment. 47 refs., 3 figs., 1 tab.

  1. A Time-Measurement System Based on Isotopic Ratios

    International Nuclear Information System (INIS)

    Vo, Duc T.; Karpius, P.J.; MacArthur, D.W.; Thron, J.L.

    2007-01-01

    A time-measurement system can be built based on the ratio of gamma-ray peak intensities from two radioactive isotopes. The ideal system would use a parent isotope with a short half-life decaying to a long half-life daughter. The activities of the parent-daughter isotopes would be measured using a gamma-ray detector system. The time can then be determined from the ratio of the activities. The best-known candidate for such a system is the 241 Pu- 241 Am parent-daughter pair. However, this 241 Pu- 241 Am system would require a high-purity germanium detector system and sophisticated software to separate and distinguish between the many gamma-ray peaks produced by the decays of the two isotopes. An alternate system would use two different isotopes, again one with a short half-life and one with a half-life that is long relative to the other. The pair of isotopes 210 Pb and 241 Am (with half-lives of 22 and 432 years, respectively) appears suitable for such a system. This time-measurement system operates by measuring the change in the ratio of the 47-keV peak of 210 Pb to the 60-keV peak of 241 Am. For the system to work reasonably well, the resolution of the detector would need to be such that the two gamma-ray peaks are well separated so that their peak areas can be accurately determined using a simple region-of-interest (ROI) method. A variety of detectors were tested to find a suitable system for this application. The results of these tests are presented here.

  2. Direct uranium isotope ratio analysis of single micrometer-sized glass particles

    International Nuclear Information System (INIS)

    Kappel, Stefanie; Boulyga, Sergei F.; Prohaska, Thomas

    2012-01-01

    We present the application of nanosecond laser ablation (LA) coupled to a ‘Nu Plasma HR’ multi collector inductively coupled plasma mass spectrometer (MC-ICP-MS) for the direct analysis of U isotope ratios in single, 10–20 μm-sized, U-doped glass particles. Method development included studies with respect to (1) external correction of the measured U isotope ratios in glass particles, (2) the applied laser ablation carrier gas (i.e. Ar versus He) and (3) the accurate determination of lower abundant 236 U/ 238 U isotope ratios (i.e. 10 −5 ). In addition, a data processing procedure was developed for evaluation of transient signals, which is of potential use for routine application of the developed method. We demonstrate that the developed method is reliable and well suited for determining U isotope ratios of individual particles. Analyses of twenty-eight S1 glass particles, measured under optimized conditions, yielded average biases of less than 0.6% from the certified values for 234 U/ 238 U and 235 U/ 238 U ratios. Experimental results obtained for 236 U/ 238 U isotope ratios deviated by less than −2.5% from the certified values. Expanded relative total combined standard uncertainties U c (k = 2) of 2.6%, 1.4% and 5.8% were calculated for 234 U/ 238 U, 235 U/ 238 U and 236 U/ 238 U, respectively. - Highlights: ► LA-MC-ICP-MS was fully validated for the direct analysis of individual particles. ► Traceability was established by using an IRMM glass particle reference material. ► Measured U isotope ratios were in agreement with the certified range. ► A comprehensive total combined uncertainty evaluation was performed. ► The analysis of 236 U/ 238 U isotope ratios was improved by using a deceleration filter.

  3. Lead (Pb) isotopic fingerprinting and its applications in lead pollution studies in China: A review

    International Nuclear Information System (INIS)

    Cheng Hefa; Hu Yuanan

    2010-01-01

    As the most widely scattered toxic metal in the world, the sources of lead (Pb) observed in contamination investigation are often difficult to identify. This review presents an overview of the principles, analysis, and applications of Pb isotopic fingerprinting in tracing the origins and transport pathways of Pb in the environment. It also summarizes the history and current status of lead pollution in China, and illustrates the power of Pb isotopic fingerprinting with examples of its recent applications in investigating the effectiveness of leaded gasoline phase-out on atmospheric lead pollution, and the sources of Pb found in various environmental media (plants, sediments, and aquatic organisms) in China. The limitations of Pb isotopic fingerprinting technique are discussed and a perspective on its development is also presented. Further methodological developments and more widespread instrument availability are expected to make isotopic fingerprinting one of the key tools in lead pollution investigation. - This review presents an overview of the principles, applications, and limitations of Pb isotopic fingerprinting in lead pollution investigation, and provides a perspective on its future development.

  4. Plutonium isotope ratios in polychaete worms

    International Nuclear Information System (INIS)

    Beasley, T.M.; Fowler, S.W.

    1976-01-01

    Reference is made to recent reports that suggest that terrestrial and aquatic organisms may preferentially take up 238 Pu compared with sup(239+240)Pu. It is stated that although kinetic isotope effects are known to occur in biological systems for low mass number elements, such as H, C and N, such effects are generally discounted with higher mass numbers, and differences in the biological 'uptake' of isotopes of high mass number elements, such as those of Pu, are normally attributable to differences in the chemical or physical forms of the isotopes or to different quantities of isotopes available to organisms. This has been applied to explain differential Pu isotope behaviour in animals under controlled laboratory conditions, but it is not certain that it can be applied to explain anomalies of Pu isotope behaviour in organisms contaminated by nuclear test debris or by wastes from nuclear fuel reprocessing plants. Geochemical weathering may also have an effect. Described here are experiments in which it was found that deposit feeding marine worms living in sediments contaminated in different ways with Pu isotopes did not show preferential accumulation of 238 Pu. The worms had been exposed to different chemical and physical forms of the isotopes, including exposure to laboratory-labelled sediment, sediment collected from a former weapons test site, and sediment contaminated by wastes from a nuclear fuel reprocessing plant. The worms were allowed to accumulate Pu for times of 5 to 40 days. Isotope ratios were determined by α-spectrometric techniques. It is considered that the results are important for environmental samples where Pu activity levels are low. (U.K.)

  5. Impact of historical mining assessed in soils by kinetic extraction and lead isotopic ratios

    International Nuclear Information System (INIS)

    Camizuli, E.; Monna, F.; Bermond, A.; Manouchehri, N.; Besançon, S.; Losno, R.; Oort, F. van; Labanowski, J.; Perreira, A.; Chateau, C.; Alibert, P.

    2014-01-01

    The aim of this study is to estimate the long-term behaviour of trace metals, in two soils differently impacted by past mining. Topsoils from two 1 km 2 zones in the forested Morvan massif (France) were sampled to assess the spatial distribution of Cd, Cu, Pb and Zn. The first zone had been contaminated by historical mining. As expected, it exhibits higher trace-metal levels and greater spatial heterogeneity than the second non-contaminated zone, supposed to represent the local background. One soil profile from each zone was investigated in detail to estimate metal behaviour, and hence, bioavailability. Kinetic extractions were performed using EDTA on three samples: the A horizon from both soil profiles and the B horizon from the contaminated soil. For all three samples, kinetic extractions can be modelled by two first-order reactions. Similar kinetic behaviour was observed for all metals, but more metal was extracted from the contaminated A horizon than from the B horizon. More surprising is the general predominance of the residual fraction over the “labile” and “less labile” pools. Past anthropogenic inputs may have percolated over time through the soil profiles because of acidic pH conditions. Stable organo-metallic complexes may also have been formed over time, reducing metal availability. These processes are not mutually exclusive. After kinetic extraction, the lead isotopic compositions of the samples exhibited different signatures, related to contamination history and intrinsic soil parameters. However, no variation in lead signature was observed during the extraction experiment, demonstrating that the “labile” and “less labile” lead pools do not differ in terms of origin. Even if trace metals resulting from past mining and metallurgy persist in soils long after these activities have ceased, kinetic extractions suggest that metals, at least for these particular forest soils, do not represent a threat for biota. - Highlights: • Trace

  6. Impact of historical mining assessed in soils by kinetic extraction and lead isotopic ratios

    Energy Technology Data Exchange (ETDEWEB)

    Camizuli, E., E-mail: estelle.camizuli@u-bourgogne.fr [UMR 6298, ArTeHiS, Université de Bourgogne — CNRS — Culture, 6 bd Gabriel, Bat. Gabriel, 21000 Dijon (France); Monna, F. [UMR 6298, ArTeHiS, Université de Bourgogne — CNRS — Culture, 6 bd Gabriel, Bat. Gabriel, 21000 Dijon (France); Bermond, A.; Manouchehri, N.; Besançon, S. [Institut des sciences et industries du vivant et de l' environnement (AgroParisTech), Laboratoire de Chimie Analytique, 16, rue Claude Bernard, 75231 Paris Cedex 05 (France); Losno, R. [UMR 7583, LISA, Universités Paris 7-Paris 12 — CNRS, 61 av. du Gal de Gaulle, 94010 Créteil Cedex (France); Oort, F. van [UR 251, Pessac, Institut National de la Recherche Agronomique, Centre de Versailles-Grignon, RD 10, 78026 Versailles Cedex (France); Labanowski, J. [UMR 7285, IC2MP, Université de Poitiers — CNRS, 4, rue Michel Brunet, 86022 Poitiers (France); Perreira, A. [UMR 6298, ArTeHiS, Université de Bourgogne — CNRS — Culture, 6 bd Gabriel, Bat. Gabriel, 21000 Dijon (France); Chateau, C. [UFR SVTE, Université de Bourgogne, 6 bd Gabriel, Bat. Gabriel, 21000 Dijon (France); Alibert, P. [UMR 6282, Biogeosciences, Université de Bourgogne — CNRS, 6 bd Gabriel, Bat. Gabriel, 21000 Dijon (France)

    2014-02-01

    The aim of this study is to estimate the long-term behaviour of trace metals, in two soils differently impacted by past mining. Topsoils from two 1 km{sup 2} zones in the forested Morvan massif (France) were sampled to assess the spatial distribution of Cd, Cu, Pb and Zn. The first zone had been contaminated by historical mining. As expected, it exhibits higher trace-metal levels and greater spatial heterogeneity than the second non-contaminated zone, supposed to represent the local background. One soil profile from each zone was investigated in detail to estimate metal behaviour, and hence, bioavailability. Kinetic extractions were performed using EDTA on three samples: the A horizon from both soil profiles and the B horizon from the contaminated soil. For all three samples, kinetic extractions can be modelled by two first-order reactions. Similar kinetic behaviour was observed for all metals, but more metal was extracted from the contaminated A horizon than from the B horizon. More surprising is the general predominance of the residual fraction over the “labile” and “less labile” pools. Past anthropogenic inputs may have percolated over time through the soil profiles because of acidic pH conditions. Stable organo-metallic complexes may also have been formed over time, reducing metal availability. These processes are not mutually exclusive. After kinetic extraction, the lead isotopic compositions of the samples exhibited different signatures, related to contamination history and intrinsic soil parameters. However, no variation in lead signature was observed during the extraction experiment, demonstrating that the “labile” and “less labile” lead pools do not differ in terms of origin. Even if trace metals resulting from past mining and metallurgy persist in soils long after these activities have ceased, kinetic extractions suggest that metals, at least for these particular forest soils, do not represent a threat for biota. - Highlights: • Trace

  7. On the interference of Kr during carbon isotope analysis of methane using continuous-flow combustion–isotope ratio mass spectrometry

    Directory of Open Access Journals (Sweden)

    J. Schmitt

    2013-05-01

    Full Text Available Stable carbon isotope analysis of methane (δ13C of CH4 on atmospheric samples is one key method to constrain the current and past atmospheric CH4 budget. A frequently applied measurement technique is gas chromatography (GC isotope ratio mass spectrometry (IRMS coupled to a combustion-preconcentration unit. This report shows that the atmospheric trace gas krypton (Kr can severely interfere during the mass spectrometric measurement, leading to significant biases in δ13C of CH4, if krypton is not sufficiently separated during the analysis. According to our experiments, the krypton interference is likely composed of two individual effects, with the lateral tailing of the doubly charged 86Kr peak affecting the neighbouring m/z 44 and partially the m/z 45 Faraday cups. Additionally, a broad signal affecting m/z 45 and especially m/z 46 is assumed to result from scattered ions of singly charged krypton. The introduced bias in the measured isotope ratios is dependent on the chromatographic separation, the krypton-to-CH4 mixing ratio in the sample, the focusing of the mass spectrometer as well as the detector configuration and can amount to up to several per mil in δ13C. Apart from technical solutions to avoid this interference, we present correction routines to a posteriori remove the bias.

  8. Lead isotopes in soils near five historic American lead smelters and refineries

    International Nuclear Information System (INIS)

    Rabinowitz, Michael B.

    2005-01-01

    This survey of soil lead in the vicinity of old industrial sites examines how the stable isotope patterns vary among the sites according to the sources of the lead ore processed at each site. Lead smelters and refineries, which closed down decades ago, are the basis of this investigation. Samples were taken from near five old factory sites in Collinsville and Alton (Illinois), Ponderay (Idaho), East Chicago (Indiana) and Omaha (Nebraska). Historical records were searched for accounts of the sources of the lead. Lead concentrations were measured by atomic absorption flame spectrophotometry, and stable isotopic analysis was done by plasma ionization mass spectrometry. At every site visited, remnants of the old factories, in terms of soil lead pollution, could be found. In spite of potential complications of varying smelter feedstock sourced from mines of different geological age, it was possible to match the isotopic patterns in the soils with the documented sources of the ores. The Collinsville and Alton sites resembled Missouri lead. The Ponderay value was higher than major Bunker Hill, Idaho deposits, but closer to the minor, nearby Oreille County, Washington ores. Mostly Utah ore was used in East Chicago. The Omaha soil reflects lead from Mexico, Colorado and Montana

  9. The use of carbon stable isotope ratios in drugs characterization

    Energy Technology Data Exchange (ETDEWEB)

    Magdas, D. A., E-mail: gabriela.cristea@itim-cj.ro; Cristea, G., E-mail: gabriela.cristea@itim-cj.ro; Bot, A., E-mail: gabriela.cristea@itim-cj.ro; Mirel, V., E-mail: gabriela.cristea@itim-cj.ro [National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath Str., 400293 Cluj-Napoca (Romania)

    2013-11-13

    Isotopic Ratio Mass Spectrometry (IRMS) is an effective toll to be used for drug product authentication. The isotopic composition could be used to assist in the differentiation between batches of drugs and assist in the identification of counterfeit materials on the market. Only two factors affect the isotopic ratios in pharmaceutical components: the isotopic composition of the raw materials and the synthetic processes performed upon them. Counterfeiting of pharmaceutical drugs threatens consumer confidence in drug products companies' economical well-being. In this preliminary study, the analyzed samples consist in two types of commercially available analgesics, which were purchases from Romanian pharmacies. Differences in δ{sup 13}C between batches from −29.7 to −31.6% were observed, demonstrating that this method can be used to differentiate among individual drug batches and subsequently identify counterfeits on the market. On the other hand, carbon isotopic ratios differences among producers were recorded, the variations being between −31.3 to −34.9% for the same type of analgesic, but from different manufactures.

  10. Asian industrial lead inputs to the North Pacific evidenced by lead concentrations and isotopic compositions in surface waters and aerosols.

    Science.gov (United States)

    Gallon, Céline; Ranville, Mara A; Conaway, Christopher H; Landing, William M; Buck, Clifton S; Morton, Peter L; Flegal, A Russell

    2011-12-01

    Recent trends of atmospheric lead deposition to the North Pacific were investigated with analyses of lead in aerosols and surface waters collected on the fourth Intergovernmental Oceanographic Commission Contaminant Baseline Survey from May to June, 2002. Lead concentrations of the aerosols varied by 2 orders of magnitude (0.1-26.4 pmol/m(3)) due in part to variations in dust deposition during the cruise. The ranges in lead aerosol enrichment factors relative to iron (1-119) and aluminum (3-168) were similar, evidencing the transport of Asian industrial lead aerosols across the North Pacific. The oceanic deposition of some of those aerosols was substantiated by the gradient of lead concentrations of North Pacific waters, which varied 3-fold (32.7-103.5 pmol/kg), were highest along with the Asian margin of the basin, and decreased eastward. The hypothesized predominance of Asian industrial lead inputs to the North Pacific was further corroborated by the lead isotopic composition of ocean surface waters ((206)Pb/(207)Pb = 1.157-1.169; (208)Pb/(206)Pb = 2.093-2.118), which fell within the range of isotopic ratios reported in Asian aerosols that are primarily attributed to Chinese industrial lead emissions.

  11. Atmospheric deposition of lead in Norway: spatial and temporal variation in isotopic composition

    International Nuclear Information System (INIS)

    Steinnes, E.; Aaberg, G.; Hjelmseth, H.

    2005-01-01

    Moss samples collected from 22 sites all over Norway at five different times during 1977-2000 were analysed for stable lead isotope ratios. These data together with total lead concentrations and relevant literature lead isotope data from UK, western/central Europe and eastern Europe/Russia were used to elucidate major source regions for lead deposited in different parts of the country at different times. The southernmost part of the country was most affected from western/central Europe around 1975, but the deposition declined rapidly and UK became a more significant source region in the 1980s. Recently, the influence is mostly from Eastern Europe. In the west, UK was the dominant source region during the whole period. In the middle and northern regions, the deposition was low but also decreasing regularly, and the main source region was probably the North Atlantic. In the far north-east, influence from Russia and eastern Europe was dominant during the whole period

  12. The lead isotopic composition of dust in the vicinity of a uranium mine in northern Australia and its use for radiation dose assessment

    International Nuclear Information System (INIS)

    Bollhoefer, Andreas; Honeybun, Russell; Rosman, Kevin; Martin, Paul

    2006-01-01

    Airborne lead isotope ratios were measured via Thermal Ionisation Mass Spectrometry in samples from the vicinity of Ranger uranium mine in northern Australia. Dust deposited on leaves of Acacia spp. was washed off and analysed to gain a geographical snapshot of lead isotope ratios in the region. Aerosols were also collected on Teflon filters that were changed monthly over one seasonal cycle using a low volume diaphragm pump. Lead isotope ratios in dust deposited on leaves overestimate the relative amount of mine origin airborne lead, most likely due to a difference of the size distribution of particles collected on leaves and true aerosol size distribution. Seasonal measurements show that the annual average mine contribution to airborne lead concentrations in Jabiru East, approximately 2.5 km northwest of the mine, amounted to 13%, with distinct differences between the wet and dry season. The relative contribution of mine origin lead deposited on leaves in the dry season drops to less than 1% at a distance of 12.5 km from the mine along the major wind direction. An approach is outlined, in which lead isotope ratios are used to estimate the effective radiation dose received from the inhalation of mine origin radioactivity trapped in or on dust. Using the data from our study, this dose has been calculated to be approximately 2 μSv year -1 for people living and working in the area

  13. Isotope systematic of contaminant leads in Monterey Bay

    International Nuclear Information System (INIS)

    Flegal, A.R.; Rosman, K.J.R.; Stephenson, M.D.

    1987-01-01

    Isotopic compositions of stable lead ( 204 Pb, 206 Pb, 207 Pb, and 208 Pb) were utilized to identify a lead slag deposit as the principal source of contaminant lead in Monterey Bay. This point source had been indicated by anomalously high lead concentrations in native mussels (Mytilus californianus) near that deposit, which were orders of magnitude above the base-line concentration of the species (0.5 μg/g). Subsequent analyses revealed that the lead concentrations of both transplanted mussels and intertidal sediments were positively correlated with their proximity to the slag deposit. Complementary lead isotopic compositions substantiated those empirical correlations by demonstrating that the slag was the predominant source of contaminant lead in both the mussels and the sediments. Analyses of the digestive tracts of mussels from the slag deposit indicated that ingested slag particulates accounted for their elevated lead concentrations, while analyses of their gonads indicated that dissolved lead from other industrial sources was also being bioaccumulated by passive adsorption on exposed surfaces. Therefore, this study has demonstrated the potential of lead isotope systematics both to identify sources of lead contamination in marine organisms and to trace its biogeochemical cycle in the marine environment. 26 references, 3 figures, 5 tables

  14. Development, optimisation, and application of ICP-SFMS methods for the measurement of isotope ratios

    International Nuclear Information System (INIS)

    Stuerup, S.

    2000-07-01

    The measurement of isotopic composition and isotope ratios in biological and environmental samples requires sensitive, precise, and accurate analytical techniques. The analytical techniques used are traditionally based on mass spectrometry, among these techniques is the ICP-SFMS technique, which became commercially available in the mid 1990s. This technique is characterised by high sensitivity, low background, and the ability to separate analyte signals from spectral interferences. These features are beneficial for the measurement of isotope ratios and enable the measurement of isotope ratios of elements, which it has not previously been possible to measure due to either spectral interferences or poor sensitivity. The overall purpose of the project was to investigate the potential of the single detector ICP-SFMS technique for the measurement of isotope ratios in biological and environmental samples. One part of the work has focused on the fundamental aspects of the ICP-SFMS technique with special emphasize on the features important to the measurement of isotope ratios, while another part has focused on the development, optimisation and application of specific methods for the measurement of isotope ratios of elements of nutritional interest and radionuclides. The fundamental aspects of the ICP-SFMS technique were investigated theoretically and experimentally by the measurement of isotope ratios applying different experimental conditions. It was demonstrated that isotope ratios could be measured reliably using ICP-SFMS by educated choice of acquisition parameters, scanning mode, mass discrimination correction, and by eliminating the influence of detector dead time. Applying the knowledge gained through the fundamental study, ICP-SFMS methods for the measurement of isotope ratios of calcium, zinc, molybdenum and iron in human samples and a method for the measurement of plutonium isotope ratios and ultratrace levels of plutonium and neptunium in environmental samples

  15. Lead isotopes reveal different sources of lead in balsamic and other vinegars

    International Nuclear Information System (INIS)

    Ndung'u, Kuria; Hibdon, Sharon; Veron, Alain; Flegal, A. Russell

    2011-01-01

    Fifty-eight brands of balsamic vinegars were analyzed for lead concentrations and isotopic compositions ( 204 Pb, 206 Pb, 207 Pb, and 208 Pb) to test the findings of a previous study indicating relatively high levels of lead contamination in some of those vinegars - more than two thirds (70%) of them exceeded California's State Maximum Level (34 μg/L) based on consumption rates ≥ 0.5 μg Pb per day. The Lead isotopic fingerprints of all those vinegars with high lead concentrations were then found to be primarily anthropogenic. This isotopic analysis unquestionably reveals multiple contamination sources including atmospheric pollutant Pb and an unidentified contamination source, likely occurring after grape harvest. Organically grown grape vinegars display the same Pb content and isotopic signatures as other vinegars. This implies that pesticides might not be a significant source of pollutant Pb in vinegars. A significant post-harvest contamination would be inherited from chemicals added during production and/or material used during transport, processing or storage of these vinegars. This is consistent with the highest Pb levels being found in aged vinegars (112 ± 112 μg/L) in contrast to other vinegars (41.6 ± 28.9 μg/L) suggesting contamination during storage. It is, therefore, projected that lead levels in most vinegars, especially aged balsamic and wine vinegars, will decrease with improvements in their manufacture and storage processes consequential to recent concerns of elevated levels of lead in some vinegars. - Highlights: → First extensive study on content and possible sources of lead in balsamic vinegars. → Half of the vinegars exceed California's State Maximum Level for human consumption. → Lead content in vinegars seems to be mainly post-harvest from industrial processes.

  16. The CN/C15N isotopic ratio towards dark clouds

    Science.gov (United States)

    Hily-Blant, P.; Pineau des Forêts, G.; Faure, A.; Le Gal, R.; Padovani, M.

    2013-09-01

    Understanding the origin of the composition of solar system cosmomaterials is a central question, not only in the cosmochemistry and astrochemistry fields, and requires various approaches to be combined. Measurements of isotopic ratios in cometary materials provide strong constraints on the content of the protosolar nebula. Their relation with the composition of the parental dark clouds is, however, still very elusive. In this paper, we bring new constraints based on the isotopic composition of nitrogen in dark clouds, with the aim of understanding the chemical processes that are responsible for the observed isotopic ratios. We have observed and detected the fundamental rotational transition of C15N towards two starless dark clouds, L1544 and L1498. We were able to derive the column density ratio of C15N over 13CN towards the same clouds and obtain the CN/C15N isotopic ratios, which were found to be 500 ± 75 for both L1544 and L1498. These values are therefore marginally consistent with the protosolar value of 441. Moreover, this ratio is larger than the isotopic ratio of nitrogen measured in HCN. In addition, we present model calculations of the chemical fractionation of nitrogen in dark clouds, which make it possible to understand how CN can be deprived of 15N and HCN can simultaneously be enriched in heavy nitrogen. The non-fractionation of N2H+, however, remains an open issue, and we propose some chemical way of alleviating the discrepancy between model predictions and the observed ratios. Appendices are available in electronic form at http://www.aanda.orgThe reduced spectra (in FITS format) are available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/557/A65

  17. Carbon isotope ratios and isotopic correlations between components in fruit juices

    Science.gov (United States)

    Wierzchnicki, Ryszard

    2013-04-01

    Nowadays food products are defined by geographical origin, method of production and by some regulations concerning terms of their authenticity. Important data for confirm the authenticity of product are providing by isotopic methods of food control. The method checks crucial criteria which characterize the authenticity of inspected product. The European Union Regulations clearly show the tendency for application of the isotopic methods for food authenticity control (wine, honey, juice). The aim of the legislation steps is the protection of European market from possibility of the commercial frauds. Method of isotope ratio mass spectrometry is very effective tool for the use distinguishably the food products of various geographical origin. The basic problem for identification of the sample origin is the lack of databases of isotopic composition of components and information about the correlations of the data. The subject of the work was study the isotopic correlations existing between components of fruits. The chemical and instrumental methods of separation: water, sugars, organic acids and pulp from fruit were implemented. IRMS technique was used to measure isotopic composition of samples. The final results for original samples of fruits (apple, strawberry etc.) will be presented and discussed. Acknowledgement: This work was supported by the Polish Ministry of Science and Higher Education under grant NR12-0043-10/2010.

  18. Examining Changes in Radioxenon Isotope Activity Ratios during Subsurface Transport

    Science.gov (United States)

    Annewandter, R.

    2013-12-01

    The Non-Proliferation Experiment (NPE) has demonstrated and modelled the usefulness of barometric pumping induced soil gas sampling during On-Site inspections. Gas transport has been widely studied with different numerical codes. However, gas transport of all radioxenons in the post-detonation regime and their possible fractionation is still neglected in the open literature. Atmospheric concentrations of the radioxenons Xe-135, Xe-133m, Xe-133 and Xe-131m can be used to discriminate between civilian releases (nuclear power plants or medical isotope facilities), and nuclear explosion sources. It is based on the isotopic activity ratio method. Yet it is not clear whether subsurface migration of the radioxenons, with eventual release into the atmosphere, can affect the activity ratios due to fractionation. Fractionation can be caused by different diffusivities due to mass differences between the radioxenons. A previous study showed surface arrival time of a chemically inert gaseous tracer is affected by its diffusivity. They observed detectable amount for SF6 50 days after detonation and 375 days for He-3. They predict 50 and 80 days for Xe-133 and Ar-37 respectively. Cyclical changes in atmospheric pressure can drive subsurface gas transport. This barometric pumping phenomenon causes an oscillatoric flow in upward trending fractures which, combined with diffusion into the porous matrix, leads to a net transport of gaseous components - a ratcheting effect. We use a general purpose reservoir simulator (Complex System Modelling Platform, CSMP++) which has been applied in a range of fields such as deep geothermal systems, three-phase black oil simulations , fracture propagation in fractured, porous media, Navier-Stokes pore-scale modelling among others. It is specifically designed to account for structurally complex geologic situation of fractured, porous media. Parabolic differential equations are solved by a continuous Galerkin finite-element method, hyperbolic

  19. Investigation of the feeding effect on the 13C/12C isotope ratio of the hormones in bovine urine using gas chromatography/combustion isotope ratio mass spectrometry

    NARCIS (Netherlands)

    Balizs, Gabor; Jainz, Annett; Horvatovich, Peter

    2005-01-01

    The effect of the feeding on the 13C/12C isotope ratio of four endogenous steroid hormones testosterone (T), epi-testosterone (epi-T), dehydroepiandrosterone (DHEA) and etiocholanolone (ETIO) in bovine urine was investigated. An analytical method to determine the accurate isotope ratio was developed

  20. Isotope Ratio Monitoring Gas Chromatography Mass Spectrometry (IRM-GCMS)

    International Nuclear Information System (INIS)

    Freeman, K.H.; Ricci, S.A.; Studley, A.; Hayes, J.M.

    1989-01-01

    On Earth, the C-13 content of organic compounds is depleted by roughly 13 to 23 permil from atmospheric carbon dioxide. This difference is largely due to isotope effects associated with the fixation of inorganic carbon by photosynthetic organisms. If life once existed on Mars, then it is reasonable to expect to observe a similar fractionation. Although the strongly oxidizing conditions on the surface of Mars make preservation of ancient organic material unlikely, carbon-isotope evidence for the existence of life on Mars may still be preserved. Carbon depleted in C-13 could be preserved either in organic compounds within buried sediments, or in carbonate minerals produced by the oxidation of organic material. A technique is introduced for rapid and precise measurement of the C-13 contents of individual organic compounds. A gas chromatograph is coupled to an isotope-ratio mass spectrometer through a combustion interface, enabling on-line isotopic analysis of isolated compounds. The isotope ratios are determined by integration of ion currents over the course of each chromatographic peak. Software incorporates automatic peak determination, corrections for background, and deconvolution of overlapped peaks. Overall performance of the instrument was evaluated by the analysis of a mixture of high purity n-alkanes of know isotopic composition. Isotopic values measured via IRM-GCMS averaged withing 0.55 permil of their conventionally measured values

  1. Lead (Pb) isotopic fingerprinting and its applications in lead pollution studies in China: a review.

    Science.gov (United States)

    Cheng, Hefa; Hu, Yuanan

    2010-05-01

    As the most widely scattered toxic metal in the world, the sources of lead (Pb) observed in contamination investigation are often difficult to identify. This review presents an overview of the principles, analysis, and applications of Pb isotopic fingerprinting in tracing the origins and transport pathways of Pb in the environment. It also summarizes the history and current status of lead pollution in China, and illustrates the power of Pb isotopic fingerprinting with examples of its recent applications in investigating the effectiveness of leaded gasoline phase-out on atmospheric lead pollution, and the sources of Pb found in various environmental media (plants, sediments, and aquatic organisms) in China. The limitations of Pb isotopic fingerprinting technique are discussed and a perspective on its development is also presented. Further methodological developments and more widespread instrument availability are expected to make isotopic fingerprinting one of the key tools in lead pollution investigation. Copyright 2009 Elsevier Ltd. All rights reserved.

  2. Measurement of boron isotope ratios in groundwater studies

    International Nuclear Information System (INIS)

    Porteous, N.C.; Walsh, J.N.; Jarvis, K.E.

    1995-01-01

    Boron is present at low levels in groundwater and rainfall in the UK, ranging between 2 and 200 ng ml -1 . A sensitive technique has been developed using inductively coupled plasma mass spectrometry (ICP-MS) to measure boron isotope ratios at low concentrations with a precision (s r ) of between 0.1 and 0.2%. Samples were evaporated to increase elemental boron concentrations to 200 ng ml -1 and interfering matrix elements were removed by an adapted cation-exchange separation procedure. The validity of measuring boron isotopic ratios by ICP-MS at this concentration level is discussed in relation to the theoretical instrument precision attainable based on counting statistics. (author)

  3. Isotope yield ratios as a probe of the reaction dynamics

    International Nuclear Information System (INIS)

    Trautmann, W.; Hildenbrand, K.D.; Lynen, U.; Mueller, W.F.J.; Rabe, H.J.; Sann, H.; Stelzer, H.; Trockel, R.; Wada, R.; Brummund, N.; Glasow, R.; Kampert, K.H.; Santo, R.; Eckert, E.M.; Pochodzalla, J.; Bock, I.; Pelte, D.

    1987-04-01

    Isotopically resolved yields of particles and complex fragments from 12 C and 18 O induced reactions on 53 Ni, 54 Ni, Ag, and 197 Au in the intermediate range of bombarding energies 30 MeV ≤ E/A ≤ 84 MeV were measured. The systematic variation of the deduced isotope yield ratios with projectile and target is used to determine the degree of N/Z equilibration achieved and to establish time scales for the reaction process. A quantum statistical model is employed in order to derive entropies of the emitting systems from the measured isotope yield ratios. (orig.)

  4. Stable isotope ratios in hair and teeth reflect biologic rhythms.

    Directory of Open Access Journals (Sweden)

    Otto Appenzeller

    Full Text Available Biologic rhythms give insight into normal physiology and disease. They can be used as biomarkers for neuronal degenerations. We present a diverse data set to show that hair and teeth contain an extended record of biologic rhythms, and that analysis of these tissues could yield signals of neurodegenerations. We examined hair from mummified humans from South America, extinct mammals and modern animals and people, both healthy and diseased, and teeth of hominins. We also monitored heart-rate variability, a measure of a biologic rhythm, in some living subjects and analyzed it using power spectra. The samples were examined to determine variations in stable isotope ratios along the length of the hair and across growth-lines of the enamel in teeth. We found recurring circa-annual periods of slow and fast rhythms in hydrogen isotope ratios in hair and carbon and oxygen isotope ratios in teeth. The power spectra contained slow and fast frequency power, matching, in terms of normalized frequency, the spectra of heart rate variability found in our living subjects. Analysis of the power spectra of hydrogen isotope ratios in hair from a patient with neurodegeneration revealed the same spectral features seen in the patient's heart-rate variability. Our study shows that spectral analysis of stable isotope ratios in readily available tissues such as hair could become a powerful diagnostic tool when effective treatments and neuroprotective drugs for neurodegenerative diseases become available. It also suggests that similar analyses of archaeological specimens could give insight into the physiology of ancient people and animals.

  5. Heavy element stable isotope ratios. Analytical approaches and applications

    International Nuclear Information System (INIS)

    Tanimizu, Masaharu; Sohrin, Yoshiki; Hirata, Takafumi

    2013-01-01

    Continuous developments in inorganic mass spectrometry techniques, including a combination of an inductively coupled plasma ion source and a magnetic sector-based mass spectrometer equipped with a multiple-collector array, have revolutionized the precision of isotope ratio measurements, and applications of inorganic mass spectrometry for biochemistry, geochemistry, and marine chemistry are beginning to appear on the horizon. Series of pioneering studies have revealed that natural stable isotope fractionations of many elements heavier than S (e.g., Fe, Cu, Zn, Sr, Ce, Nd, Mo, Cd, W, Tl, and U) are common on Earth, and it had been widely recognized that most physicochemical reactions or biochemical processes induce mass-dependent isotope fractionation. The variations in isotope ratios of the heavy elements can provide new insights into past and present biochemical and geochemical processes. To achieve this, the analytical community is actively solving problems such as spectral interference, mass discrimination drift, chemical separation and purification, and reduction of the contamination of analytes. This article describes data calibration and standardization protocols to allow interlaboratory comparisons or to maintain traceability of data, and basic principles of isotope fractionation in nature, together with high-selectivity and high-yield chemical separation and purification techniques for stable isotope studies.

  6. Biometrics from the carbon isotope ratio analysis of amino acids in human hair.

    Science.gov (United States)

    Jackson, Glen P; An, Yan; Konstantynova, Kateryna I; Rashaid, Ayat H B

    2015-01-01

    This study compares and contrasts the ability to classify individuals into different grouping factors through either bulk isotope ratio analysis or amino-acid-specific isotope ratio analysis of human hair. Using LC-IRMS, we measured the isotope ratios of 14 amino acids in hair proteins independently, and leucine/isoleucine as a co-eluting pair, to provide 15 variables for classification. Multivariate analysis confirmed that the essential amino acids and non-essential amino acids were mostly independent variables in the classification rules, thereby enabling the separation of dietary factors of isotope intake from intrinsic or phenotypic factors of isotope fractionation. Multivariate analysis revealed at least two potential sources of non-dietary factors influencing the carbon isotope ratio values of the amino acids in human hair: body mass index (BMI) and age. These results provide evidence that compound-specific isotope ratio analysis has the potential to go beyond region-of-origin or geospatial movements of individuals-obtainable through bulk isotope measurements-to the provision of physical and characteristic traits about the individuals, such as age and BMI. Further development and refinement, for example to genetic, metabolic, disease and hormonal factors could ultimately be of great assistance in forensic and clinical casework. Copyright © 2014 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

  7. Simultaneous stable carbon isotopic analysis of wine glycerol and ethanol by liquid chromatography coupled to isotope ratio mass spectrometry.

    Science.gov (United States)

    Cabañero, Ana I; Recio, Jose L; Rupérez, Mercedes

    2010-01-27

    A novel procedure was established for the simultaneous characterization of wine glycerol and ethanol (13)C/(12)C isotope ratio, using liquid chromatography/isotope ratio mass spectrometry (LC-IRMS). Several parameters influencing separation of glycerol and ethanol from wine matrix were optimized. Results obtained for 35 Spanish samples exposed no significant differences and very strong correlations (r = 0.99) between the glycerol (13)C/(12)C ratios obtained by an alternative method (gas chromatography/isotope ratio mass spectrometry) and the proposed new methodology, and between the ethanol (13)C/(12)C ratios obtained by the official method (elemental analyzer/isotope ratio mass spectrometry) and the proposed new methodology. The accuracy of the proposed method varied from 0.01 to 0.19 per thousand, and the analytical precision was better than 0.25 per thousand. The new developed LC-IRMS method it is the first isotopic method that allows (13)C/(12)C determination of both analytes in the same run directly from a liquid sample with no previous glycerol or ethanol isolation, overcoming technical difficulties associated with complex sample treatment and improving in terms of simplicity and speed.

  8. Dynamics of radioactive lead isotopes in the global environmental atmosphere

    International Nuclear Information System (INIS)

    Koike, Yuya; Kosako, Toshiso

    2006-01-01

    Fundamental information of radioactive lead isotopes, which used as the atmospheric tracer in the global environmental atmosphere, is reviewed. Emanation and exhalation of Rn and Tn, parent nuclide, is stated. Some reports on measurement and application of short-lived lead isotopes are reported. Transfer of radioactive lead isotopes in the atmosphere, vertical profiles of radon, thoron, and short-lived lead isotopes for different turbulent mixing conditions, deposition to aerosol, basic processes of Rn decay product behavior in air defining 'unattached' and 'aerosol-attached' activities, seasonal variation of atmospheric 210 Pb concentration at Beijing and Chengdu, seasonal variation of atmospheric 212 Pb concentration at several observation sites in Japan Islands, and variation in the atmospheric concentration of 212 Pb along with SO 2 are shown. (S.Y.)

  9. Broadband non-selective excitation of plutonium isotopes for isotope ratio measurements in resonance ionization mass spectrometry: a theoretical study.

    Science.gov (United States)

    Sankari, M

    2012-10-15

    Making isotope ratio measurements with minimum isotope bias has always been a challenging task to mass spectrometrists, especially for the specific case of plutonium, owing to the strategic importance of the element. In order to use resonance ionization mass spectrometry (RIMS) as a tool for isotope ratio measurements, optimization of the various laser parameters and other atomic and system parameters is critical to minimize isotopic biases. Broadband simultaneous non-selective excitation of the isotopes of plutonium in the triple resonance excitation scheme with λ(1) = 420.77 nm, λ(2) = 847.28 nm, and λ(3) = 767.53 nm based on density matrix formalism has been theoretically computed for the determination of isotope ratios. The effects of the various laser parameters and other factors such as the atomization temperature and the dimensions of the atomic beam on the estimation of isotope ratios were studied. The effects of Doppler broadening, and time-dependent excitation parameters such as Rabi frequencies, ionization rate and the effect of non-Lorenztian lineshape have all been incorporated. The average laser powers and bandwidths for the three-excitation steps were evaluated for non-selective excitation. The laser intensity required to saturate the three-excitation steps were studied. The two-dimensional lineshape contour and its features were investigated, while the reversal of peak asymmetry of two-step and two-photon excitation peaks under these conditions is discussed. Optimized powers for the non-selective ionization of the three transitions were calculated as 545 mW, 150 mW and 545 mW and the laser bandwidth for all the three steps was ~20 GHz. The isotopic bias between the resonant and off-resonant isotope under the optimized conditions was no more than 9%, which is better than an earlier reported value. These optimized laser power and bandwidth conditions are better than in the earlier experimental work since these comprehensive calculations yield

  10. Isotopically tailored lead target with reduced polonium and bismuth radio-waste

    International Nuclear Information System (INIS)

    Khorasanov, G.L.; Ivanov, A.P.; Lunev, V.P.; Blokhin, A.I.

    2002-01-01

    Residual activity of a lead target after 1 year irradiation with a high power, 0.8 GeV*30 mA, proton beam is studied. It is concluded that the main radiotoxicity of irradiated lead is connected with bismuth isotope, Bi-207, which is produced in natural lead, mix of several stable isotopes, via (p,2n) reaction with Pb-208 nuclei. It is proposed to use, as a target material, lead enriched with another stable isotope, Pb-206, in order to reduce producing Bi-207 and Po-210. Estimation of charges for obtaining large quantities of lead-206 is also given. Accumulation of hazardous radionuclides, Bi-207, Bi-208, and Po-210, in natural lead to be used as a coolant in future fast reactors and accelerator driven reactors is predicted. In accelerator driven systems a large portion of Bi-207 can be produced via Pb-208(p,2n)Bi-207 reaction in a target of natural lead (Pb-208/Pb-207/Pb-206/Pb-204=52.35/22.08/24.14/1.42 %). A new isotopically tailored coolant-converter for ADS consisting of lead isotope, Pb-206, is proposed. By using this material, it is possible to reduce essentially the production of the most radio-toxic isotopes of Bi and Po and to avoid disposing the large amounts of lead. To provide the future fast reactors and accelerator driven systems with low-activation coolant - converter, the new technology of obtaining the large amounts of natural lead enriched with lead isotope, Pb-206, should be developed. (authors)

  11. Direct uranium isotope ratio analysis of single micrometer-sized glass particles.

    Science.gov (United States)

    Kappel, Stefanie; Boulyga, Sergei F; Prohaska, Thomas

    2012-11-01

    We present the application of nanosecond laser ablation (LA) coupled to a 'Nu Plasma HR' multi collector inductively coupled plasma mass spectrometer (MC-ICP-MS) for the direct analysis of U isotope ratios in single, 10-20 μm-sized, U-doped glass particles. Method development included studies with respect to (1) external correction of the measured U isotope ratios in glass particles, (2) the applied laser ablation carrier gas (i.e. Ar versus He) and (3) the accurate determination of lower abundant (236)U/(238)U isotope ratios (i.e. 10(-5)). In addition, a data processing procedure was developed for evaluation of transient signals, which is of potential use for routine application of the developed method. We demonstrate that the developed method is reliable and well suited for determining U isotope ratios of individual particles. Analyses of twenty-eight S1 glass particles, measured under optimized conditions, yielded average biases of less than 0.6% from the certified values for (234)U/(238)U and (235)U/(238)U ratios. Experimental results obtained for (236)U/(238)U isotope ratios deviated by less than -2.5% from the certified values. Expanded relative total combined standard uncertainties U(c) (k = 2) of 2.6%, 1.4% and 5.8% were calculated for (234)U/(238)U, (235)U/(238)U and (236)U/(238)U, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. Isotopic approach to the provenance study of artifacts

    International Nuclear Information System (INIS)

    Mabuchi, Hisao

    1994-01-01

    Isotopic abundance ratios, which are proved to be generally constant, are known to vary, for certain elements, from one place to another. Light elements, such as hydrogen, lithium, boron, carbon, nitrogen, oxygen and sulfur, show measurable variations of their isotope ratios due to isotopic fractionation which takes place during geochemical or biochemical processes. Isotope ratios of strontium and lead vary due to the decay of long-lived radioactive nuclides 87 Rb and 238 U- 235 U- 232 Th, respectively. Such isotopic anomalies can be applicable to provenance studies of archaeological objects. Thus, 13 C/ 12 C, 18 O/ 16 O, or 87 Sr/ 86 Sr were used to examine the authenticity of Greek marble statues. Also, lead isotope ratios have been used since mid-1960s extensively for provenance studies of glasses and bronzes of different civilizations. As an example, the author presents a series of his own works on lead isotope ratios applied to ancient Japanese bronzes, which are summarized as follows. 1) It was generally observed that lead isotope ratios reflect difference in culture to which bronzes belong. 2) Mirrors in the Western Han period (206 B.C. - A.D.8) are clearly distinguished by lead isotope ratios from those made after the mid-Eastern Han period (ca.A.D.150 - 300). 3) Korean mirrors and weapons excavated from the Yayoi sites contain lead of easily recognizable Mississippi Valley type. 4) Bronze objects made in Japan (imitative Han style mirrors, Dotaku, imitative weapons, arrowheads etc.) in the Yayoi and Kofun periods are classified by lead isotope ratios in the following order: the Korean mirror type to the Western Han mirror type in the Yayoi period and the mid- to post- Han mirror type in the Kofun period. 5) Indigenous Japanese lead seems to have been used after the mid-7th century. (J.P.N.)

  13. Isotopic ratios of 129I/127I in mammalian thyroid glands in Japan

    International Nuclear Information System (INIS)

    Seki, R.; Hatano, T.

    1994-01-01

    The isotopic ratios of 129 I/ 127 I in cattle thyroid glands collected from various areas of Japan were measured by neutron activation analysis with combustion pre-treatment. Pig and human thyroid glands were also analyzed by the same method. The iodine isotopic ratio in cattle thyroid glands in Japan is comparable with that observed in Europe. The isotopic ratio in human thyroid glands in Japan is remarkably lower than that in Europe, which has been reported to be comparable to that of cattle. The isotopic ratio in pig thyroid glands is also lower than that in cattle. (author) 7 refs.; 3 figs.; 5 tabs

  14. Constraining recent lead pollution sources in the North Pacific using ice core stable lead isotopes

    Science.gov (United States)

    Gross, B. H.; Kreutz, K. J.; Osterberg, E. C.; McConnell, J. R.; Handley, M.; Wake, C. P.; Yalcin, K.

    2012-08-01

    Trends and sources of lead (Pb) aerosol pollution in the North Pacific rim of North America from 1850 to 2001 are investigated using a high-resolution (subannual to annual) ice core record recovered from Eclipse Icefield (3017 masl; St. Elias Mountains, Canada). Beginning in the early 1940s, increasing Pb concentration at Eclipse Icefield occurs coevally with anthropogenic Pb deposition in central Greenland, suggesting that North American Pb pollution may have been in part or wholly responsible in both regions. Isotopic ratios (208Pb/207Pb and 206Pb/207Pb) from 1970 to 2001 confirm that a portion of the Pb deposited at Eclipse Icefield is anthropogenic, and that it represents a variable mixture of East Asian (Chinese and Japanese) emissions transported eastward across the Pacific Ocean and a North American component resulting from transient meridional atmospheric flow. Based on comparison with source material Pb isotope ratios, Chinese and North American coal combustion have likely been the primary sources of Eclipse Icefield Pb over the 1970-2001 time period. The Eclipse Icefield Pb isotope composition also implies that the North Pacific mid-troposphere is not directly impacted by transpolar atmospheric flow from Europe. Annually averaged Pb concentrations in the Eclipse Icefield ice core record show no long-term trend during 1970-2001; however, increasing208Pb/207Pb and decreasing 206Pb/207Pb ratios reflect the progressive East Asian industrialization and increase in Asian pollutant outflow. The post-1970 decrease in North American Pb emissions is likely necessary to explain the Eclipse Icefield Pb concentration time series. When compared with low (lichen) and high (Mt. Logan ice core) elevation Pb data, the Eclipse ice core record suggests a gradual increase in pollutant deposition and stronger trans-Pacific Asian contribution with rising elevation in the mountains of the North Pacific rim.

  15. Carbon isotope ratios in field Population II giant stars

    International Nuclear Information System (INIS)

    Sneden, C.; Pilachowski, C.A.; Vandenberg, D.A.; Kitt Peak National Observatory, Tucson, AZ; Victoria Univ., Canada)

    1986-01-01

    Carbon isotope ratios have been derived from high-resolution spectra of the CH G-band in 15 very metal-poor Population II giant stars and two similar dwarf stars. Many of the giants possess very low C-12/C-13 ratios, some approaching the CN cycle equilibrium value. The metal-poor dwarfs do not have detectable CH-13 features; thus the low carbon isotope ratios in the giants probably are due to their internal evolutions. These results strongly support the idea that at least part of the anomalously low C/N values in Population II giants arises from very efficient mixing of their envelopes into the CN cycle burning layers. Detailed calculations of the expected CNO surface abundances in Population II giants in different evolutionary states have been performed. These computations demonstrate that the observed carbon isotope ratios cannot be produced during the first dredge-up mixing phases in low-mass, low metal abundance stars. Numerical experiments show that theoretical and observational results can be brought into agreement with artificially induced extra mixing. An agent to provoke this additional mixing has not been identified with certainty yet, although internal stellar rotation is a promising candidate. 63 references

  16. Online stable carbon isotope ratio measurement in formic acid, acetic acid, methanol and ethanol in water by high performance liquid chromatography-isotope ratio mass spectrometry

    International Nuclear Information System (INIS)

    Tagami, Keiko; Uchida, Shigeo

    2008-01-01

    A suitable analysis condition was determined for high performance liquid chromatography-isotope ratio mass spectrometry (HPLC-IRMS) while making sequential measurements of stable carbon isotope ratios of δ 13 C in formic acid, acetic acid, methanol and ethanol dissolved in water. For this online column separation method, organic reagents are not applicable due to carbon contamination; thus, water and KH 2 PO 4 at low concentrations were tested as mobile phase in combination with a HyPURITY AQUASTAR TM column. Formic acid, acetic acid, methanol and ethanol were separated when 2 mM KH 2 PO 4 aqueous solution was used. Under the determined analysis condition for HPLC-IRMS, carbon concentrations could be measured quantitatively as well as carbon isotope ratio when carbon concentration was higher than 0.4 mM L for each chemical

  17. Sulfur isotope ratios and the origins of the aerosols and cloud droplets in California stratus

    International Nuclear Information System (INIS)

    Ludwig, F.L.

    1976-01-01

    Marine aerosols often have sulfur-to-chloride ratios greater than that found in seawater. Sulfur isotope ratios ( 34 S/ 32 S) were measured in aerosol and cloud droplet samples collected in the San Francisco Bay Area in an attempt to understand the processes that produce the observed sulfur-to-chloride ratios. Seawater sulfur usually has very high sulfur isotope ratios: fossil fuel sulfur tends to have smaller isotope ratios and sulfur of bacteriogenic origin still smaller. Samples collected in unpolluted marine air over the hills south of San Francisco had sulfur ratios that were significantly lower than the values for samples collected in nearby areas that were subject to urban pollution. The highest sulfur isotope ratios were found in the offshore seawater. The results suggest bacteriogenic origins, of the marine air sulfur aerosol material. The low isotope ratios in the marine air cannot be explained as a mixture of seawater sulfur and pollutant sulfur, because both tend to have higher isotope ratios. (Auth.)

  18. A Plant-Based Proxy for the Oxygen Isotope Ratio of Atmospheric Water Vapor

    Science.gov (United States)

    Helliker, B.

    2007-12-01

    Atmospheric water vapor is a major component of the global hydrological cycle, but the isotopic balance of vapor is largely unknown. It is shown here that the oxygen isotope ratio of leaf water in the epiphytic Crassulacean acid metabolism (CAM) plant Tillandsia usneoides (Spanish Moss) is controlled by the oxygen isotope ratio of atmospheric water vapor in both field and lab studies. Assuming that the leaf-water isotopic signature (and hence the atmospheric water vapor signature) is recorded in plant organic material, the atmospheric water vapor oxygen isotope ratios for Miami, Florida (USA) were reconstructed for several years from 1878 to 2005 using contemporary and herbarium specimens. T. usneoides ranges from Virginia, USA southwards through the tropics to Argentina, and the CAM epiphytic lifeform is widespread in other species. Therefore, epiphytes may be used to reconstruct the isotope ratio of atmospheric water for spatial scales that span over 60° of latitude and temporal scales that cover the last century of global temperature increase.

  19. Measurement of stable isotope ratio of organic carbon in water samples

    International Nuclear Information System (INIS)

    Fujii, Toshihiro; Otsuki, Akira

    1977-01-01

    A new method for the measurement of stable isotope ratios was investigated and applied to organic carbon's isotope ratio measurements in water samples. A few river water samples from Tsuchiura city were tested. After the wet oxidation of organic carbons to carbon dioxide in a sealed ampoule, the isotope ratios were determined with the gas chromatograph-quadrupole mass spectrometer combined with a total organic carbon analyser, under the dynamic conditions. The GC-MS had been equipped with the multiple ion detector-digital integrator system. The ion intensities at m/e 44 and 45 were simultaneously measured at a switching rate of 1 ms. The measurements with carbon dioxide acquired from sodium carbonate (53 μg) gave the isotope ratios with the variation coefficient of 0.62%. However, the variation coefficients obtained from organic carbons in natural water samples were 2 to 3 times as high as that from sodium carbonate. This method is simple and rapid and may be applied to various fields especially in biology and medicine. (auth.)

  20. Optimal sample to tracer ratio for isotope dilution mass spectrometry: the polyisotopic case

    International Nuclear Information System (INIS)

    Laszlo, G.; Ridder, P. de; Goldman, A.; Cappis, J.; Bievre, P. de

    1991-01-01

    The Isotope Dilution Mass Spectrometry (IDMS) measurement technique provides a means for determining the unknown amount of various isotopes of an element in a sample solution of known mass. The sample solution is mixed with an auxiliary solution, or tracer, containing a known amount of the same element having the same isotopes but of different relative abundances or isotopic composition and the induced change in the isotopic composition measured by isotope mass spectrometry. The technique involves the measurement of the abundance ratio of each isotope to a (same) reference isotope in the sample solution, in the tracer solution and in the blend of the sample and tracer solution. These isotope ratio measurements, the known element amount in the tracer and the known mass of sample solution are used to calculate the unknown amount of one isotope in the sample solution. Subsequently the unknown amount of element is determined. The purpose of this paper is to examine the optimization of the ratio of the estimated unknown amount of element in the sample solution to the known amount of element in the tracer solution in order to minimize the relative uncertainty in the determination of the unknown amount of element

  1. Examining Changes in Radioxenon Isotope Activity Ratios during Subsurface Transport

    Science.gov (United States)

    Annewandter, Robert

    2014-05-01

    The Non-Proliferation Experiment (NPE) has demonstrated and modelled the usefulness of barometric pumping induced gas transport and subsequent soil gas sampling during On-Site inspections. Generally, gas transport has been widely studied with different numerical codes. However, gas transport of radioxenons and radioiodines in the post-detonation regime and their possible fractionation is still neglected in the open peer-reviewed literature. Atmospheric concentrations of the radioxenons Xe-135, Xe-133m, Xe-133 and Xe-131m can be used to discriminate between civilian releases (nuclear power plants or medical isotope facilities), and nuclear explosion sources. It is based on the multiple isotopic activity ratio method. Yet it is not clear whether subsurface migration of the radionuclides, with eventual release into the atmosphere, can affect the activity ratios due to fractionation. Fractionation can be caused by different mass diffusivities due to mass differences between the radionuclides. Cyclical changes in atmospheric pressure can drive subsurface gas transport. This barometric pumping phenomenon causes an oscillatoric flow in upward trending fractures or highly conductive faults which, combined with diffusion into the porous matrix, leads to a net transport of gaseous components - a so-called ratcheting effect. We use a general purpose reservoir simulator (Complex System Modelling Platform, CSMP++) which is recognized by the oil industry as leading in Discrete Fracture-Matrix (DFM) simulations. It has been applied in a range of fields such as deep geothermal systems, three-phase black oil simulations, fracture propagation in fractured, porous media, and Navier-Stokes pore-scale modelling among others. It is specifically designed to account for structurally complex geologic situation of fractured, porous media. Parabolic differential equations are solved by a continuous Galerkin finite-element method, hyperbolic differential equations by a complementary finite

  2. The thermal history of char as disclosed by carbon isotope ratios

    DEFF Research Database (Denmark)

    Egsgaard, Helge; Ambus, Per; Ahrenfeldt, Jesper

    In laboratory experiments, biomass char was produced under controlled conditions using wood chips from French pinewood. Different char qualities were obtained by pyrolysing the biomass at similar heating rates with end-temperatures ranging from 250 to 1000 o C. The char was analysed by flash...... pyrolysis and isotope ratio mass spectrometry. The results demonstrate that the temperature history of the char is reflected in the fine variation of carbon isotopes. The compound classes responsible for the variation were identified. Key words: Isotope ratio, flash pyrolysis, hot gas cleaning...

  3. The potential of elemental and isotopic analysis of tree bark for discriminating sources of airborne lead contamination in the UK.

    Science.gov (United States)

    Bellis, D; McLeod, C W; Satake, K

    2001-02-01

    Samples of tree bark, which accumulate airborne material, were collected from seven locations in the UK to provide an indication of the magnitude and source of lead pollution. Measurement of the Pb content and 206/207Pb stable isotope ratio by inductively coupled plasma mass spectrometry revealed significant differences between the sites. The concentration of Pb varied over almost four orders of magnitude from 7.2 to 9,600 micrograms g-1, the maximum values being found near a 'secondary' Pb smelter. The 206/207Pb isotope ratios varied from 1.108 +/- 0.002 to 1.169 +/- 0.001. The lowest Pb concentrations and highest isotope ratios were detected in bark samples from the Scilly Isles, reflecting the low-level of industry and road traffic. In contrast, samples obtained from a city centre (Sheffield) and near a motorway (M1) contained 25-46 micrograms g-1 Pb and recorded the lowest 206/207Pb ratios. Higher concentrations in the vicinity of a coal-fired power station recorded a 206/207Pb ratio of 1.14, suggesting a significant contribution from fly-ash. The relative contribution of lead from petrol (206/207Pb = 1.08) and other sources such as coal (206/207Pb = 1.18) were thus estimated using mass balance equations. Tree bark near the lead smelter recorded an intermediate 206/207Pb ratio of 1.13 reflecting the processing of material of mixed origin.

  4. Isotope ratios as pollutant source and behaviour indicators

    International Nuclear Information System (INIS)

    1975-01-01

    Recent years have witnessed significant advances in isotope techniques for identifying origins and for studying the behaviour of trace contaminants and pollutants of the environment under actual existing environmental conditions. Improvements in the supply of stable isotopes and their labelled compounds, instrumental analysis and information on stable or radioactive isotopic ratios of existing environmental contaminants as a function of origin or behaviour have provided relatively new tools for the environmental scientist. While variations in natural or existing environmental stable and radioactive nuclides could be regarded as 'background noise' in conventional tracer experiments they promised unique information about sources and behaviour to those who listened carefully. (author)

  5. Lead-isotope inhomogeneity in Precambrian igneous K-feldspars

    International Nuclear Information System (INIS)

    Ludwig, K.R.; Silver, L.T.

    1977-01-01

    Stepwise PB-removal experiments, using both vacuum volatilization and HF-leaching techniques, on acid-washed K-feldspar concentrates from Precambrian igneous rocks show that all contain some unsupported radiogenic Pb. Two types of radiogenic Pb were recognised. One has a 'normal' isotopic composition, with relative abundances of 206 Pb, 207 Pb and 208 Pb consistent with the age and U-Th contents of the rocks. The other type of unsupported radiogenic lead in the feldspars is apparently pure 206 Pb, derived from long-term migration and accumulation of radioactive daughter(s) of 238 U. This 'pure' 206 Pb lead occupies different sites from the 'normal' radiogenic lead, and tends to show a release maximum during vacuum volatilization at about 1150 0 C. The usefulness of stepwise vacuum volatilization may be limited by the tendency of a small amount of radiogenic lead to concentrate in the least volatile fraction. Stepwise partial HF attacks appear to give at least as good separation of radiogenic from original feldspar lead, and are recommended as a routine procedure for isotopic analyses of Precambrian feldspars. The fact that most of the five K-feldspars examined contained unsupported radiogenic lead implies that caution must be used in applying total-sample lead analyses of Precambrian feldspars to problems of lead-isotope evolution in crustal rocks. (author)

  6. Geospatial modeling of plant stable isotope ratios - the development of isoscapes

    Science.gov (United States)

    West, J. B.; Ehleringer, J. R.; Hurley, J. M.; Cerling, T. E.

    2007-12-01

    Large-scale spatial variation in stable isotope ratios can yield critical insights into the spatio-temporal dynamics of biogeochemical cycles, animal movements, and shifts in climate, as well as anthropogenic activities such as commerce, resource utilization, and forensic investigation. Interpreting these signals requires that we understand and model the variation. We report progress in our development of plant stable isotope ratio landscapes (isoscapes). Our approach utilizes a GIS, gridded datasets, a range of modeling approaches, and spatially distributed observations. We synthesize findings from four studies to illustrate the general utility of the approach, its ability to represent observed spatio-temporal variability in plant stable isotope ratios, and also outline some specific areas of uncertainty. We also address two basic, but critical questions central to our ability to model plant stable isotope ratios using this approach: 1. Do the continuous precipitation isotope ratio grids represent reasonable proxies for plant source water?, and 2. Do continuous climate grids (as is or modified) represent a reasonable proxy for the climate experienced by plants? Plant components modeled include leaf water, grape water (extracted from wine), bulk leaf material ( Cannabis sativa; marijuana), and seed oil ( Ricinus communis; castor bean). Our approaches to modeling the isotope ratios of these components varied from highly sophisticated process models to simple one-step fractionation models to regression approaches. The leaf water isosocapes were produced using steady-state models of enrichment and continuous grids of annual average precipitation isotope ratios and climate. These were compared to other modeling efforts, as well as a relatively sparse, but geographically distributed dataset from the literature. The latitudinal distributions and global averages compared favorably to other modeling efforts and the observational data compared well to model predictions

  7. A lead isotopic study of the human bioaccessibility of lead in urban soils from Glasgow, Scotland

    International Nuclear Information System (INIS)

    Farmer, John G.; Broadway, Andrew; Cave, Mark R.; Wragg, Joanna; Fordyce, Fiona M.; Graham, Margaret C.; Ngwenya, Bryne T.; Bewley, Richard J.F.

    2011-01-01

    The human bioaccessibility of lead (Pb) in Pb-contaminated soils from the Glasgow area was determined by the Unified Bioaccessibility Research Group of Europe (BARGE) Method (UBM), an in vitro physiologically based extraction scheme that mimics the chemical environment of the human gastrointestinal system and contains both stomach and intestine compartments. For 27 soils ranging in total Pb concentration from 126 to 2160 mg kg -1 (median 539 mg kg -1 ), bioaccessibility as determined by the 'stomach' simulation (pH ∼ 1.5) was 46-1580 mg kg -1 , equivalent to 23-77% (mean 52%) of soil total Pb concentration. The corresponding bioaccessibility data for the 'stomach + intestine' simulation (pH ∼ 6.3) were 6-623 mg kg -1 and 2-42% (mean 22%) of soil Pb concentration. The soil 206 Pb/ 207 Pb ratios ranged from 1.057 to 1.175. Three-isotope plots of 208 Pb/ 206 Pb against 206 Pb/ 207 Pb demonstrated that 206 Pb/ 207 Pb ratios were intermediate between values for source end-member extremes of imported Australian Pb ore (1.04) - used in the manufacture of alkyl Pb compounds (1.06-1.10) formerly added to petrol - and indigenous Pb ores/coal (1.17-1.19). The 206 Pb/ 207 Pb ratios of the UBM 'stomach' extracts were similar ( 206 Pb/ 207 Pb ratio was discernible in the UBM. However, the source of Pb appeared to be less important in determining the extent of UBM-bioaccessible Pb than the overall soil total Pb concentration and the soil phases with which the Pb was associated. The significant phases identified in a subset of samples were carbonates, manganese oxides, iron-aluminium oxyhydroxides and clays. - Highlights: → We determined the human bioaccessibility of Pb in urban soils by in vitro extraction. → We determined the isotopic composition of Pb in soils and simulated stomach extracts. → Soil stable Pb isotope ratios (e.g. 206 Pb/ 207 Pb) indicated a range of sources of Pb. → 206 Pb/ 207 Pb ratios in soils and their simulated stomach extracts were very similar

  8. Levels and source apportionment of children's lead exposure: Could urinary lead be used to identify the levels and sources of children's lead pollution?

    International Nuclear Information System (INIS)

    Cao, Suzhen; Duan, Xiaoli; Zhao, Xiuge; Wang, Beibei; Ma, Jin; Fan, Delong; Sun, Chengye; He, Bin; Wei, Fusheng; Jiang, Guibin

    2015-01-01

    As a highly toxic heavy metal, the pollution and exposure risks of lead are of widespread concern for human health. However, the collection of blood samples for use as an indicator of lead pollution is not always feasible in most cohort or longitudinal studies, especially those involving children health. To evaluate the potential use of urinary lead as an indicator of exposure levels and source apportionment, accompanying with environmental media samples, lead concentrations and isotopic measurements (expressed as 207 Pb/ 206 Pb, 208 Pb/ 206 Pb and 204 Pb/ 206 Pb) were investigated and compared between blood and urine from children living in the vicinities of a typical coking plant and lead-acid battery factory. The results showed urinary lead might not be a preferable proxy for estimating blood lead levels. Fortunately, urinary lead isotopic measurements could be used as an alternative for identifying the sources of children's lead exposure, which coincided well with the blood lead isotope ratio analysis. - Highlights: • Pb isotopes of environmental media and children's blood and urine were analyzed. • Pb exposure and pollution source were studied in lead-acid battery and coking areas. • Pb isotope ratios in blood and urine were similar to those of food, water and PM. • Urine Pb level may not be used as a proxy for indicating the lead levels in blood. • Urine Pb isotope ratios is an alternative to identify source and exposure pathways. - Urinary lead is not a preferable proxy to estimate blood lead level, but urinary lead isotope ratios could be an alternative for identifying the sources of lead exposure in children

  9. Investigating the origin of Pb pollution in a terrestrial soil-plant-snail food chain by means of Pb isotope ratios

    Energy Technology Data Exchange (ETDEWEB)

    Notten, M.J.M. [Institute of Ecological Science, Department of System Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands)], E-mail: m.notten@nunhems.com; Walraven, N. [Faculty of Geosciences, Department of Earth Sciences/Geochemistry, University of Utrecht, Budapestlaan 4, 3508 TA Utrecht (Netherlands); Beets, C.J. [Institute of Earth Sciences, Department of Quaternary Geology and Geomorphology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands); Vroon, P. [Institute of Earth Sciences, Department of Petrology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands); Rozema, J.; Aerts, R. [Institute of Ecological Science, Department of System Ecology, Vrije Universiteit Amsterdam, De Boelelaan 1085, 1081 HV, Amsterdam (Netherlands)

    2008-06-15

    Lead isotope ratios were used to trace the origin of Pb in a soil-plant (Urtica dioica)-snail (Cepaea nemoralis) food chain in two polluted locations in the floodplains of the rivers Meuse and Rhine (Biesbosch National Park) and one reference location in the Netherlands. Lead isotope ratios and concentrations were determined in soil, litter, plant leaves, snails, rainwater and airborne particulate matter. Anthropogenic Pb in the soils of all locations was found to be derived from deposition of Pb polluted river sediments. Discharging rivers influenced the reference location before being reclaimed from the sea. The river sediment contains anthropogenic Pb from various sources related to industrial activities in the hinterland of the rivers Meuse and Rhine. Lead in the atmosphere contributed substantially to Pb pollution and Pb transfer in plant leaves and snails in all locations. Lead pollution in plant leaves and snails can be explained from a mixture of river sediment-Pb and atmospheric Pb from various transfer routes that involve low concentrations.

  10. Investigating the origin of Pb pollution in a terrestrial soil-plant-snail food chain by means of Pb isotope ratios

    International Nuclear Information System (INIS)

    Notten, M.J.M.; Walraven, N.; Beets, C.J.; Vroon, P.; Rozema, J.; Aerts, R.

    2008-01-01

    Lead isotope ratios were used to trace the origin of Pb in a soil-plant (Urtica dioica)-snail (Cepaea nemoralis) food chain in two polluted locations in the floodplains of the rivers Meuse and Rhine (Biesbosch National Park) and one reference location in the Netherlands. Lead isotope ratios and concentrations were determined in soil, litter, plant leaves, snails, rainwater and airborne particulate matter. Anthropogenic Pb in the soils of all locations was found to be derived from deposition of Pb polluted river sediments. Discharging rivers influenced the reference location before being reclaimed from the sea. The river sediment contains anthropogenic Pb from various sources related to industrial activities in the hinterland of the rivers Meuse and Rhine. Lead in the atmosphere contributed substantially to Pb pollution and Pb transfer in plant leaves and snails in all locations. Lead pollution in plant leaves and snails can be explained from a mixture of river sediment-Pb and atmospheric Pb from various transfer routes that involve low concentrations

  11. Isotopic Ratios of Samarium by TIMS for Nuclear Forensic Application

    Energy Technology Data Exchange (ETDEWEB)

    Louis Jean, James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Inglis, Jeremy David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-08-08

    The isotopic ratio of Nd, Sm, and Gd can provide important information regarding fissile material (nuclear devices, reactors), neutron environment, and device yield. These studies require precise measurement of Sm isotope ratios, by either TIMS or MC-ICP-MS. There has been an increasing trend to measure smaller and smaller quantities of Sm bearing samples. In nuclear forensics 10-100 ng of Sm are needed for precise measurement. To measure sub-ng Sm samples using TIMS for nuclear forensic analysis.

  12. Carbon isotope ratios of atmospheric carbon dioxide

    International Nuclear Information System (INIS)

    Sakai, Hitoshi; Kishima, Noriaki; Tsutaki, Yasuhiro.

    1982-01-01

    The delta 13 C values relative to PDB were measured for carbon dioxide in air samples collected at various parts of Japan and at Mauna Loa Observatory, Hawaii in the periods of 1977 and 1978. The delta 13 C values of the ''clean air'' are -7.6 % at Hawaii and -8.1 per mille Oki and Hachijo-jima islands. These values are definitely lighter than the carbon isotope ratios (-6.9 per mille) obtained by Keeling for clean airs collected at Southern California in 1955 to 1956. The increase in 12 C in atmospheric carbon dioxide is attributed to the input of the anthropogenic light carbon dioxides (combustion of fossil fuels etc.) Taking -7.6 per mille to be the isotope ratio of CO 2 in the present clean air, a simple three box model predicts that the biosphere has decreased rather than increased since 1955, implying that it is acting as the doner of carbon rather than the sink. (author)

  13. Stable isotope methods: The effect of gut contents on isotopic ratios of zooplankton

    Science.gov (United States)

    Hill, J. M.; McQuaid, C. D.

    2011-05-01

    In the past decade there has been an increased awareness of the potential for methodological bias resulting from multiple pre-analytical procedures in foodweb interpretations based on stable isotope techniques. In the case of small organisms, this includes the effect of gut contents on whole body signatures. Although gut contents may not reflect actual assimilation, their carbon and nitrogen values will be isotopically lighter than after the same material has been assimilated. The potential skewing of isotopic ratios in whole organism samples is especially important for aquatic environments as many studies involve trophic relationships among small zooplankton. This is particularly important in pelagic waters, where herbivorous zooplankton comprise small taxa. Hence this study investigated the effect of gut contents on the δ13C and δ15N ratios of three size classes of zooplankton (1.0-2.0, 2.0-4.0 and >4.0 mm) collected using bongo net tows in the tropical waters of the south-west Indian Ocean. Animals were collected at night, when they were likely to be feeding, sieved into size classes and separated into genera. We focused on Euphausia spp which dominated zooplankton biomass. Three treatment types were processed: bulk animals, bulk animals without guts and tail muscle from each size class at 10 bongo stations. The δ15N ratios were influenced by zooplankton size class, presumably reflecting ontogenetic changes in diet. ANOVA post hoc results and correlations in δ15N signatures among treatments suggest that gut contents may not affect overall nitrogen signatures of Euphausia spp., but that δ13C signatures may be significantly altered by their presence. Carbon interpretations however, were complicated by potential effects of variation in chitin, lipids and metabolism among tissues and the possibility of opportunistic omnivory. Consequently we advocate gut evacuation before sacrifice in euphausiids if specific tissue dissection is impractical and recommend

  14. Differentiation of endogenous and exogenous steroids by gas chromatography-combustion-mass spectrometry isotope ratio

    International Nuclear Information System (INIS)

    Montes de Oca Porto, Rodny; Rosado Perez, Aristides; Correa Vidal, Margarita Teresa

    2007-01-01

    Urinary steroids profiles are used to control the misuse of endogenous steroids such as testosterone and dihydrotestosterone. The testosterone/epistestosterone ratio, measured by Gas Chromatography-Mass Spectrometry, is used to control testosterone administration. When T/E ratio is higher than 4, consumption of testosterone or its precursors is suspected. Recent researches have demonstrated the effectiveness of Carbon Isotope Ratio Mass Spectrometry to detect and confirm endogenous steroids administration. The ratio of the two stable carbon isotopes 1 3 C and 1 2 C allows the differentiation of natural and synthetic steroids because synthetic steroids have lower 1 3 C abundance. In fact, the carbon isotope ratios can be used to determine endogenous steroids administration even when testosterone/epistestosterone ratio is at its normal value. In the current work, some of the most important aspects related to differentiation of endogenous and exogenous steroids by means of Gas Chromatography-Combustion-Isotope Ratio Mass Spectrometry are discussed. Also, this article provides a review about the purification and sample preparation previous to the analysis, and diet effects on carbon isotope ratio of endogenous anabolics steroids is presented too

  15. Carbon Isotopic Ratios of Amino Acids in Stardust-Returned Samples

    Science.gov (United States)

    Elsila, Jamie E.; Glavin, Daniel P.; Dworkin, Jason P.

    2009-01-01

    NASA's Stardust spacecraft returned to Earth samples from comet 81P/Wild 2 in January 2006. Preliminary examinations revealed the presence of a suite of organic compounds including several amines and amino acids, but the origin of these compounds could not be identified. Here. we present the carbon isotopic ratios of glycine and E-aminocaproic acid (EACH), the two most abundant amino acids observed, in Stardust-returned foil samples measured by gas chromatography-combustion-isotope ratio crass spectrometry coupled with quadrupole mass spectrometry (GC-QMS/IRMS).

  16. Non-chondritic iron isotope ratios in planetary mantles as a result of core formation

    Science.gov (United States)

    Elardo, Stephen M.; Shahar, Anat

    2017-02-01

    Information about the materials and conditions involved in planetary formation and differentiation in the early Solar System is recorded in iron isotope ratios. Samples from Earth, the Moon, Mars and the asteroid Vesta reveal significant variations in iron isotope ratios, but the sources of these variations remain uncertain. Here we present experiments that demonstrate that under the conditions of planetary core formation expected for the Moon, Mars and Vesta, iron isotopes fractionate between metal and silicate due to the presence of nickel, and enrich the bodies' mantles in isotopically light iron. However, the effect of nickel diminishes at higher temperatures: under conditions expected for Earth's core formation, we infer little fractionation of iron isotopes. From our experimental results and existing conceptual models of magma ocean crystallization and mantle partial melting, we find that nickel-induced fractionation can explain iron isotope variability found in planetary samples without invoking nebular or accretionary processes. We suggest that near-chondritic iron isotope ratios of basalts from Mars and Vesta, as well as the most primitive lunar basalts, were achieved by melting of isotopically light mantles, whereas the heavy iron isotope ratios of terrestrial ocean floor basalts are the result of melting of near-chondritic Earth mantle.

  17. Plutonium speciation and isotope ratios in Yenisey and Ob river and Yenisey estuary

    International Nuclear Information System (INIS)

    Skipperud, L.; Oughton, DH.; Fifield, K.; Lind, O.C.; Salbu, B.; Brown, J.

    2004-01-01

    Plutonium isotope ratios are known to vary with reactor type, nuclear fuel-burn up time, neutron flux, and energy, and for fallout from nuclear detonations, weapon type and yield. Weapons-grade plutonium is characterized by a low content of the 240 Pu isotope, with 240 Pu/ 239 Pu isotope ratio less than 0.05. In contrast, both global weapons fallout and spent nuclear fuel from civil reactors have higher 240 Pu/ 239 Pu isotope ratios (civil nuclear power reactors have 240 Pu/ 239 Pu atom ratios of between about 0.2-1). Thus, different sources often exhibit characteristic plutonium isotope ratios and these ratios can be used to identify the origin of contamination, calculate inventories, or follow the migration of contaminated sediments and waters. Together with activity measurements and isotope ratios, knowledge of plutonium speciation in the Ob and Yenisey rivers and processes controlling its behaviour in estuarine systems is a prerequisite for predicting the transfer and subsequent environmental impact to Arctic Seas. With this in mind, the study had two objectives: first to determine whether discharges from nuclear installations in the river catchment areas are having any influence on Pu levels in the estuaries; and, second, to investigate the transfer and mobility of plutonium in the Yenisey river and estuary. Plutonium 240/239 ratios were determined using accelerator mass spectrometry (AMS). The data indicated a clear influence from a low 240 Pu: 239 Pu source in surface sediments collected from the Yenisey Estuary, whereas plutonium in the Ob Estuary sediments are dominated by global fallout. The results also show an increase in plutonium concentration and a decrease in isotope ratio going upstream from the estuary. Sequential extractions of sediments indicate that up 70% of the Pu in the Yenisey river is easily mobilized with weak oxidizing agents, which indicates that the Pu is organically bound, while the Pu is more strongly irreversible bound further out

  18. Triplet states in lead isotopes

    International Nuclear Information System (INIS)

    Naz, Tabassum; Ahmad, Shakeb; Abusara, H.

    2017-01-01

    Axial and triaxial calculations within RHB have been done to study the shape coexistence phenomena in the lead isotopes. Triplet states have been found in the 184-190 Pb which are in accordance with the experimental and other theoretical observations. The energy difference (in MeV) between the first two excited states also gives the evidence for the same

  19. Silicon isotope ratio measurements by inductively coupled plasma tandem mass spectrometry for alteration studies of nuclear waste glasses

    Energy Technology Data Exchange (ETDEWEB)

    Gourgiotis, Alkiviadis, E-mail: alkiviadis.gourgiotis@irsn.fr [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-DGE/SRTG/LT2S, Fontenay-aux-Roses (France); Ducasse, Thomas [CEA, DEN, DTCD, SECM, F-30207 Bagnols-sur-Cèze (France); Barker, Evelyne [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-DGE/SRTG/LT2S, Fontenay-aux-Roses (France); Jollivet, Patrick; Gin, Stéphane [CEA, DEN, DTCD, SECM, F-30207 Bagnols-sur-Cèze (France); Bassot, Sylvain; Cazala, Charlotte [Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PRP-DGE/SRTG/LT2S, Fontenay-aux-Roses (France)

    2017-02-15

    High-level, long-lived nuclear waste arising from spent fuel reprocessing is vitrified in silicate glasses for final disposal in deep geologic formations. In order to better understand the mechanisms driving glass dissolution, glass alteration studies, based on silicon isotope ratio monitoring of {sup 29}Si-doped aqueous solutions, were carried out in laboratories. This work explores the capabilities of the new type of quadrupole-based ICP-MS, the Agilent 8800 tandem quadrupole ICP-MS/MS, for accurate silicon isotope ratio determination for alteration studies of nuclear waste glasses. In order to avoid silicon polyatomic interferences, a new analytical method was developed using O{sub 2} as the reaction gas in the Octopole Reaction System (ORS), and silicon isotopes were measured in mass-shift mode. A careful analysis of the potential polyatomic interferences on SiO{sup +} and SiO{sub 2}{sup +} ion species was performed, and we found that SiO{sup +} ion species suffer from important polyatomic interferences coming from the matrix of sample and standard solutions (0.5M HNO{sub 3}). For SiO{sub 2}{sup +}, no interferences were detected, and thus, these ion species were chosen for silicon isotope ratio determination. A number of key settings for accurate isotope ratio analysis like, detector dead time, integration time, number of sweeps, wait time offset, memory blank and instrumental mass fractionation, were considered and optimized. Particular attention was paid to the optimization of abundance sensitivity of the quadrupole mass filter before the ORS. We showed that poor abundance sensitivity leads to a significant shift of the data away from the Exponential Mass Fractionation Law (EMFL) due to the spectral overlaps of silicon isotopes combined with different oxygen isotopes (i.e. {sup 28}Si{sup 16}O{sup 18}O{sup +}, {sup 30}Si{sup 16}O{sup 16}O{sup +}). The developed method was validated by measuring a series of reference solutions with different {sup 29}Si

  20. Stable strontium isotopic ratios from archaeological organic remains from the Thorsberg peat bog

    DEFF Research Database (Denmark)

    Nosch, Marie-Louise Bech; von Carnap-Bornheim, Claus; Grupe, Gisela

    2007-01-01

    Pilot study analysing stable strontium isotopic ratios from Iron Age textile and leather finds from the Thorsberg peat bog.......Pilot study analysing stable strontium isotopic ratios from Iron Age textile and leather finds from the Thorsberg peat bog....

  1. A lead isotope perspective on urban development in ancient Naples.

    Science.gov (United States)

    Delile, Hugo; Keenan-Jones, Duncan; Blichert-Toft, Janne; Goiran, Jean-Philippe; Arnaud-Godet, Florent; Romano, Paola; Albarède, Francis

    2016-05-31

    The influence of a sophisticated water distribution system on urban development in Roman times is tested against the impact of Vesuvius volcanic activity, in particular the great eruption of AD 79, on all of the ancient cities of the Bay of Naples (Neapolis). Written accounts on urbanization outside of Rome are scarce and the archaeological record sketchy, especially during the tumultuous fifth and sixth centuries AD when Neapolis became the dominant city in the region. Here we show that isotopic ratios of lead measured on a well-dated sedimentary sequence from Neapolis' harbor covering the first six centuries CE have recorded how the AD 79 eruption was followed by a complete overhaul of Neapolis' water supply network. The Pb isotopic signatures of the sediments further reveal that the previously steady growth of Neapolis' water distribution system ceased during the collapse of the fifth century AD, although vital repairs to this critical infrastructure were still carried out in the aftermath of invasions and volcanic eruptions.

  2. Variations in lead isotopic abundances in Sprague-Dawley rat tissues: possible reason of formation.

    Directory of Open Access Journals (Sweden)

    Duojian Liu

    Full Text Available It has been reported in previous research that the lead isotopic composition of blood, urine and feces samples statistically differed from the given lead sources in Sprague-Dawley (SD rats. However, the reason for this phenomenon is still unclear. An animal experiment was performed to investigate the lead isotope fractionation in diverse biological samples (i.e., lungs, liver, kidneys, bone and to explore the possible reasons. SD rats were intratracheally instilled with lead acetate at the concentrations of 0, 0.02, 0.2, and 2 mg/kg body weight. Biological samples were collected for lead isotope analysis using an inductively coupled plasma mass spectrometry (ICP-MS. Significant differences are observed in lead isotope abundances among the diverse biological samples. The lead isotope abundances ((206Pb, (207Pb and (208Pb in diverse biological samples show different degrees and directions of departure from the given lead source. The results suggest that differences in enrichment or depletion capacity for each lead isotope in the various tissues might lead to the variation in lead isotopic abundances in tissues. Moreover, a nonlinear relationship between the blood lead level and the lead isotope abundances in liver and bone is observed. When the whole-blood level is higher than 50 ng/mL, the lead isotopic compositions of biological samples tend to be the same. Thus, the data support the speculation of a fractionation functional threshold.

  3. Forensic Applications of Light-Element Stable Isotope Ratios of Ricinus communis Seeds and Ricin Preparations

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzer, Helen W.; West, Jason B.; Ehleringer, James

    2013-01-01

    Seeds of the castor plant Ricinus communis, also known as castor beans, are of forensic interest because they are the source of the poison ricin. We have tested whether stable isotope ratios of castor seeds and ricin prepared by various methods can be used as a forensic signature. We collected over 300 castor seed samples from locations around the world and measured the C, N, O, and H stable isotope ratios of the whole seeds, oil, and three types of ricin preparations. Our results demonstrate that N isotope ratios can be used to correlate ricin prepared by any of these methods to source seeds. Further, stable isotope ratios distinguished >99% of crude and purified ricin protein samples in pair-wise comparison tests. Stable isotope ratios therefore constitute a valuable forensic signature for ricin preparations.

  4. Silicon isotope ratio measurements by inductively coupled plasma tandem mass spectrometry for alteration studies of nuclear waste glasses.

    Science.gov (United States)

    Gourgiotis, Alkiviadis; Ducasse, Thomas; Barker, Evelyne; Jollivet, Patrick; Gin, Stéphane; Bassot, Sylvain; Cazala, Charlotte

    2017-02-15

    High-level, long-lived nuclear waste arising from spent fuel reprocessing is vitrified in silicate glasses for final disposal in deep geologic formations. In order to better understand the mechanisms driving glass dissolution, glass alteration studies, based on silicon isotope ratio monitoring of 29 Si-doped aqueous solutions, were carried out in laboratories. This work explores the capabilities of the new type of quadrupole-based ICP-MS, the Agilent 8800 tandem quadrupole ICP-MS/MS, for accurate silicon isotope ratio determination for alteration studies of nuclear waste glasses. In order to avoid silicon polyatomic interferences, a new analytical method was developed using O 2 as the reaction gas in the Octopole Reaction System (ORS), and silicon isotopes were measured in mass-shift mode. A careful analysis of the potential polyatomic interferences on SiO + and SiO 2 + ion species was performed, and we found that SiO + ion species suffer from important polyatomic interferences coming from the matrix of sample and standard solutions (0.5M HNO 3 ). For SiO 2 + , no interferences were detected, and thus, these ion species were chosen for silicon isotope ratio determination. A number of key settings for accurate isotope ratio analysis like, detector dead time, integration time, number of sweeps, wait time offset, memory blank and instrumental mass fractionation, were considered and optimized. Particular attention was paid to the optimization of abundance sensitivity of the quadrupole mass filter before the ORS. We showed that poor abundance sensitivity leads to a significant shift of the data away from the Exponential Mass Fractionation Law (EMFL) due to the spectral overlaps of silicon isotopes combined with different oxygen isotopes (i.e. 28 Si 16 O 18 O + , 30 Si 16 O 16 O + ). The developed method was validated by measuring a series of reference solutions with different 29 Si enrichment. Isotope ratio trueness, uncertainty and repeatability were found to be

  5. Containing arsenic-enriched groundwater tracing lead isotopic compositions of common arsenical pesticides in a coastal Maine watershed

    Science.gov (United States)

    Ayuso, Robert A.; Foley, Nora K.; Robinson, Glipin R.; Colvin, A.S.; Lipfert, G.; Reeve, A.S.

    2006-01-01

    Arsenical pesticides and herbicides were extensively used on apple, blueberry, and potato crops in New England during the first half of the twentieth century. Lead arsenate was the most heavily used arsenical pesticide until it was officially banned. Lead arsenate, calcium arsenate, and sodium arsenate have similar Pb isotope compositions: 208Pb207Pb = 2.3839-2.4722, and 206Pb207Pb = 1.1035-1.2010. Other arsenical pesticides such as copper acetoarsenite (Paris green), methyl arsonic acid and methane arsonic acid, as well as arsanilic acid are widely variable in isotope composition. Although a complete understanding of the effects of historical use of arsenical pesticides is not available, initial studies indicate that arsenic and lead concentrations in stream sediments in New England are higher in agricultural areas that intensely used arsenical pesticides than in other areas. The Pb isotope compositions of pesticides partially overlap values of stream sediments from areas with the most extensive agricultural use. The lingering effects of arsenical pesticide use were tested in a detailed geochemical and isotopic study of soil profiles from a watershed containing arsenic-enriched ground water in coastal Maine. Acid-leach compositions of the soils represent lead adsorbed to mineral surfaces or held in soluble minerals (Fe- and Mn-hydroxides, carbonate, and some micaceous minerals), whereas residue compositions likely reflect bedrock compositions. The soil profiles contain labile Pb (acid-leach) showing a moderate range in 206Pb 207Pb (1.1870-1.2069), and 208Pb207Pb (2.4519-2.4876). Isotope values vary as a function of depth: the lowest Pb isotope ratios (e.g.,208Pb206Pb) representing labile lead are in the uppermost soil horizons. Lead contents decrease with depth in the soil profiles. Arsenic contents show no clear trend with depth. A multi-component mixing scheme that included lead from the local parent rock (Penobscot Formation), lead derived from combustion of

  6. Routine lead isotope determinations using a lead-207-lead-204 double spike: a long-term assessment of analytical precision and accuracy

    International Nuclear Information System (INIS)

    Woodhead, J.D.; McCulloch, M.T.; Volker, F.

    1995-01-01

    Lead-isotope data obtained on a multicollector mass spectrometer over a four year period using a 207 Pb- 204 Pb double spike to correct for the effects of mass discrimination, are reported. Considerable improvements in both precision and accuracy over conventional correction procedures were noted, without recourse to rigorous loading or run conditions. An external precision in 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb ratios ± 0.003, 0.003 and 0.01 (2 x standard deviation), respectively, is routinely obtainable independent of minor variations in loading and run parameters. (author)

  7. Stable lead isotopes in environmental health with emphasis on human investigations

    International Nuclear Information System (INIS)

    Gulson, Brian

    2008-01-01

    There has been widespread use of stable lead isotopes in the earth sciences for more than 40 years focussed on the origin and age of rocks and minerals with lesser application in environmental investigations where the emphasis has been directed typically to the source of lead in environmental media such as air, water and soils. In contrast, the number of environmental health investigations focussed on humans (and primates) is limited in spite of the demonstrated utility of the approach in pioneering studies in the early 1970's. This paper reviews the status of lead isotopes in human investigations especially over the past 2 decades, the period over which most activity has taken place. Following a brief introduction to the method, examples are provided illustrating the use of lead isotopes in a wide spectrum of activities including sources and pathways of lead in diverse environments from urban to mining communities, various applications associated with pregnancy, the contribution of bone lead to blood lead including in the elderly, the half-life of lead in blood, and lead in bones and other media. A brief outline of critical research on non-human primates is also given. The lead isotope method is a powerful technique for tracing lead and could be employed more widely in human investigations

  8. Seawater calcium isotope ratios across the Eocene-Oligocene transition

    Science.gov (United States)

    Griffith, E.M.; Paytan, A.; Eisenhauer, A.; Bullen, T.D.; Thomas, E.

    2011-01-01

    During the Eocene-Oligocene transition (EOT, ca. 34 Ma), Earth's climate cooled significantly from a greenhouse to an icehouse climate, while the calcite (CaCO3) compensation depth (CCD) in the Pacific Ocean increased rapidly. Fluctuations in the CCD could result from various processes that create an imbalance between calcium (Ca) sources to, and sinks from, the ocean (e.g., weathering and CaCO3 deposition), with different effects on the isotopic composition of dissolved Ca in the oceans due to differences in the Ca isotopic composition of various inputs and outputs. We used Ca isotope ratios (??44/40Ca) of coeval pelagic marine barite and bulk carbonate to evaluate changes in the marine Ca cycle across the EOT. We show that the permanent deepening of the CCD was not accompanied by a pronounced change in seawater ??44/40Ca, whereas time intervals in the Neogene with smaller carbonate depositional changes are characterized by seawater ??44/40Ca shifts. This suggests that the response of seawater ??44/40Ca to changes in weathering fluxes and to imbalances in the oceanic alkalinity budget depends on the chemical composition of seawater. A minor and transient fluctuation in the Ca isotope ratio of bulk carbonate may reflect a change in isotopic fractionation associated with CaCO3 precipitation from seawater due to a combination of factors, including changes in temperature and/or in the assemblages of calcifying organisms. ?? 2011 Geological Society of America.

  9. Forensic utility of the carbon isotope ratio of PVC tape backings

    Science.gov (United States)

    Stern, L. A.; Thompson, A. H.; Mehltretter, A. H.; McLaskey, V.; Parish, A.; Aranda, R.

    2008-12-01

    Forensic interest in adhesive tapes with PVC-backings (polyvinyl chloride, electrical tapes) derives from their use in construction of improvised explosive devices, drug packaging and in a variety of other illicit activities. Due to the range of physical characteristics and chemical compositions of such tapes, traditional microscopic and chemical analysis of the tape backings and adhesives offer a high degree of discrimination between tapes from different manufacturers and products. To evaluate whether carbon isotope ratios may be able to increase discrimination of electrical tapes, particularly with regards to different tapes of the same product, we assessed the PVC-backings of 87 rolls of black electrical tape for their δ13C values. The adhesive on these tapes was physically removed with hexane, and plasticizers within the PVC tape backings were removed by three-20 minute extractions with chloroform. The δ13C values of the PVC tape backings ranged between -23.8 and -41.5 (‰ V-PDB). The carbon isotopic variation within a product (identical brand and product identification) is significant, based on five products with at least 3 rolls (ranges of 7.4‰ (n=3), 10.0‰ (n=6), 4.2‰ (n=16), 3.8‰ (n=6), and 11.5‰ (n=8), respectively). There was no measurable carbon isotope variation in regards to the following: a) along the length of a roll (4 samples from 1 roll); b) between the center and edge of a strip of tape (1 pair); c) between rolls assumed to be from the same lot of tape (2 pairs); d) between different rolls from the same batch of tape (same product purchased at the same time and place; 5 pairs); and e) between samples of a tape at room temperature, heated to 50° C and 80° C for 1 week. For each sample within the population of 87 tapes, carbon isotopes alone exclude 80 to 100% of the tapes as a potential match, with an average exclusion power of 92.5%, using a window of ± 0.4‰. Carbon isotope variations originate from variations in starting

  10. Computer-controlled detection system for high-precision isotope ratio measurements

    International Nuclear Information System (INIS)

    McCord, B.R.; Taylor, J.W.

    1986-01-01

    In this paper the authors describe a detection system for high-precision isotope ratio measurements. In this new system, the requirement for a ratioing digital voltmeter has been eliminated, and a standard digital voltmeter interfaced to a computer is employed. Instead of measuring the ratio of the two steadily increasing output voltages simultaneously, the digital voltmeter alternately samples the outputs at a precise rate over a certain period of time. The data are sent to the computer which calculates the rate of charge of each amplifier and divides the two rates to obtain the isotopic ratio. These results simulate a coincident measurement of the output of both integrators. The charge rate is calculated by using a linear regression method, and the standard error of the slope gives a measure of the stability of the system at the time the measurement was taken

  11. Locally Grown, Natural Ingredients? The Isotope Ratio Can Reveal a Lot!

    Science.gov (United States)

    Rossier, Joël S; Maury, Valérie; Pfammatter, Elmar

    2016-01-01

    This communication gives an overview of selected isotope analyses applied to food authenticity assessment. Different isotope ratio detection technologies such as isotope ratio mass spectrometry (IRMS) and cavity ring down spectroscopy (CRDS) are briefly described. It will be explained how δ(18)O of water contained in fruits and vegetables can be used to assess their country of production. It will be explained why asparagus grown in Valais, in the centre of the Alps carries much less heavy water than asparagus grown closer to the sea coast. On the other hand, the use of δ(13)C can reveal whether a product is natural or adulterated. Applications including honey or sparkling wine adulteration detection will be briefly presented.

  12. Romanian wines characterization with CF-IRMS (Continuous Flow Isotope Ratio Mass Spectrometry) isotopic analysis

    International Nuclear Information System (INIS)

    Costinel, Diana; Ionete, Roxana Elena; Vremera, Raluca; Stanciu, Vasile

    2007-01-01

    Wine growing has been known for centuries long in Romania. The country has been favored by its geographical position in south-eastern Europe, by its proximity to the Black Sea, as well as by the specificity of the local soil and climate. Alongside France, Italy, Spain, Germany, countries in this area like Romania could also be called 'a vine homeland' in Europe. High quality wines produced in this region were object of trade ever since ancient times. Under current EU research projects, it is necessary to develop new methods of evidencing wine adulteration and safety. The use of mass spectrometry (MS) to determine the ratios of stable isotopes in bio-molecules now provides the means to prove the botanical and geographical origin of a wide variety of foodstuffs - and therefore, to authenticate and eliminate fraud. Isotope analysis has been officially adopted by the EU as a means of controlling adulteration of wine. Adulteration of wine can happen in many ways, e.g. addition of non-grape ethanol, addition of non-grape sugar, water or other unauthorized substances, undeclared mixing of wines from different wards, geographical areas or countries, mislabelling of variety and age. The present paper emphasize the isotopic analysis for D/H, 18 O/ 16 O, 13 C/ 12 C from wines, using a new generation Isotope Ratio MS, Finnigan Delta V Plus, coupling with a three flexible continuous flow preparation device (GasBench II, TC Elemental Analyser and GC-C/TC). Therefore authentication of wines is an important problem to which isotopic analysis has made a significant contribution. (authors)

  13. The puzzle of the CNO isotope ratios in asymptotic giant branch carbon stars

    Science.gov (United States)

    Abia, C.; Hedrosa, R. P.; Domínguez, I.; Straniero, O.

    2017-03-01

    Context. The abundance ratios of the main isotopes of carbon, nitrogen and oxygen are modified by the CNO-cycle in the stellar interiors. When the different dredge-up events mix the burning material with the envelope, valuable information on the nucleosynthesis and mixing processes can be extracted by measuring these isotope ratios. Aims: Previous determinations of the oxygen isotopic ratios in asymptotic giant branch (AGB) carbon stars were at odds with the existing theoretical predictions. We aim to redetermine the oxygen ratios in these stars using new spectral analysis tools and further develop discussions on the carbon and nitrogen isotopic ratios in order to elucidate this problem. Methods: Oxygen isotopic ratios were derived from spectra in the K-band in a sample of galactic AGB carbon stars of different spectral types and near solar metallicity. Synthetic spectra calculated in local thermodynamic equillibrium (LTE) with spherical carbon-rich atmosphere models and updated molecular line lists were used. The CNO isotope ratios derived in a homogeneous way, were compared with theoretical predictions for low-mass (1.5-3 M⊙) AGB stars computed with the FUNS code assuming extra mixing both during the RGB and AGB phases. Results: For most of the stars the 16O/17O/18O ratios derived are in good agreement with theoretical predictions confirming that, for AGB stars, are established using the values reached after the first dredge-up (FDU) according to the initial stellar mass. This fact, as far as the oxygen isotopic ratios are concerned, leaves little space for the operation of any extra mixing mechanism during the AGB phase. Nevertheless, for a few stars with large 16O/17O/18O, the operation of such a mechanism might be required, although their observed 12C/13C and 14N/15N ratios would be difficult to reconcile within this scenario. Furthermore, J-type stars tend to have lower 16O/17O ratios than the normal carbon stars, as already indicated in previous studies

  14. Uncertainties achievable for uranium isotope-amount ratios. Estimates based on the precision and accuracy of recent characterization measurements

    International Nuclear Information System (INIS)

    Mathew, K.J.; Essex, R.M.; Gradle, C.; Narayanan, U.

    2015-01-01

    Certified reference materials (CRMs) recently characterized by the NBL for isotope-amount ratios are: (i) CRM 112-A, Uranium (normal) Metal Assay and Isotopic Standard, (ii) CRM 115, Uranium (depleted) Metal Assay and Isotopic Standard, and (iii) CRM 116-A, Uranium (enriched) Metal Assay and Isotopic Standard. NBL also completed re-characterization of the isotope-amount ratios in CRM 125-A, Uranium (UO 2 ) Pellet Assay, Isotopic, and Radio-chronometric Standard. Three different TIMS analytical techniques were employed for the characterization analyses. The total evaporation technique was used for the major isotope-amount ratio measurement, the modified total evaporation technique was used for both the major and minor isotope-amount ratios, and minor isotope-amount ratios were also measured using a Conventional technique. Uncertainties for the characterization studies were calculated from the combined TIMS data sets following the ISO Guide to the expression of uncertainty in measurement. The uncertainty components for the isotope-amount ratio values are discussed. (author)

  15. Impact on the environment from steel bridge paint deterioration using lead isotopic tracing, paint compositions and soil deconstruction

    Energy Technology Data Exchange (ETDEWEB)

    Gulson, Brian, E-mail: brian.gulson@mq.edu.au [Department of Environmental Science, Macquarie University, Sydney, NSW 2109 (Australia); CSIRO Energy Flagship, North Ryde, NSW 2113 (Australia); Chiaradia, Massimo [Department of Mineralogy, University of Geneva, Geneva (Switzerland); Davis, Jeffrey [CSIRO Energy Flagship, North Ryde, NSW 2113 (Australia); O' Connor, Gary [Queensland Department of Environment & Heritage Protection, Brisbane, QLD 4000 (Australia)

    2016-04-15

    Deterioration and repair of lead paint on steel structures can result in contamination of the ambient environment but other sources of lead such as from past use of leaded paint and gasoline and industrial activities can also contribute to the contamination. Using a combination of high precision lead isotopic tracing, detailed paint examination, including with scanning electron microscopy, and soil deconstruction we have compared paint on a steel bridge and bulk soil and lead-rich particles separated from soil. The majority of Pb found in the paint derives from Australian sources but some also has a probable US origin. The isotopic data for the bulk soils and selected particles lie on a mixing line with end members the geologically ancient Broken Hill lead and possible European lead which is suggested to be derived from old lead paint and industrial activities. Data for gasoline-derived particulates lie on this array and probably contribute to soil Pb. Although paint from the bridge can be a source of lead in the soils, isotopic tracing, paint morphology and mineralogical identification indicate that other sources, including from paint, gasoline and industrial activities, are contributing factors to the lead burden. Even though physical characteristics and elemental composition are the same in some particles, the isotopic signatures demonstrate that the sources are different. Plots using {sup 206}Pb/{sup 208}Pb vs {sup 206}Pb/{sup 207}Pb ratios, the common representation these days, do not allow for source discrimination in this investigation. - Highlights: • Soil Pb values up to 1200 mg/kg below Pb painted bridge • Microscopy & SEM characterised up to 6 different paint layers. • Isotopes identified different sources of Pb including paint and gasoline. • Multiple methods provide definitive answers.

  16. Continuous flow isotope ratio mass spectrometer (CF-IRMS) and its applications in hydrocarbon research and exploration

    International Nuclear Information System (INIS)

    Kalpana, G.; Patil, D.J.; Kumar, B.

    2004-01-01

    Stable isotope ratio mass spectrometers have been widely used to determine the isotopic ratios of light elements such as hydrogen, carbon, nitrogen, oxygen and sulphur. Continuous Flow Isotope Ratio Mass Spectrometry (CFIRMS) provides reliable data on nanomole amount of sample gas without the need for cryogenic trapping using cold fingers as in dual inlet isotope ratio mass spectrometer. High sample throughput is achieved as the system is configured with automated sample preparation devices and auto samplers. This paper presents a brief description of CFIRMS exploration

  17. A Microdrop Generator for the Calibration of a Water Vapor Isotope Ratio Spectrometer

    NARCIS (Netherlands)

    Iannone, Rosario Q.; Romanini, Daniele; Kassi, Samir; Meijer, Harro A. J.; Kerstel, Erik R. Th.

    A microdrop generator is described that produces water vapor with a known isotopic composition and volume mixing ratio for the calibration of a near-infrared diode laser water isotope ratio spectrometer. The spectrometer is designed to measure in situ the water vapor deuterium and oxygen ((17)O and

  18. A versatile method for simultaneous stable carbon isotope analysis of DNA and RNA nucleotides by liquid chromatography/isotope ratio mass spectrometry

    NARCIS (Netherlands)

    Moerdijk-Poortvliet, T.C.W.; Brasser, J.; de Ruiter, G.; Houtekamer, M.; Bolhuis, H.; Stal, L.J.; Boschker, H.T.S.

    2014-01-01

    RATIONALELiquid chromatography/isotope ratio mass spectrometry (LC/IRMS) is currently the most accurate and precise technique for the measurement of compound-specific stable carbon isotope ratios (C-13/C-12) in biological metabolites, at their natural abundance. However, until now this technique

  19. Pb concentrations and isotope ratios of soil O and C horizons in Nord-Trøndelag, central Norway: Anthropogenic or natural sources?

    International Nuclear Information System (INIS)

    Reimann, C.; Fabian, K.; Flem, B.; Schilling, J.; Roberts, D.; Englmaier, P.

    2016-01-01

    Soil O and C horizon samples (N = 752) were collected at a sample density of 1 site/36 km"2 in Nord-Trøndelag and parts of Sør-Trøndelag (c. 25,000 km"2), and analysed for Pb and three of the four naturally occurring Pb isotopes ("2"0"6Pb, "2"0"7Pb and "2"0"8Pb) in a HNO_3/HCl extraction. Soil O and C horizons are decoupled in terms of both Pb concentrations and Pb isotope ratios. In the soil C horizon the Grong-Olden Culmination, a continuous exposure of the Precambrian crystalline basement across the general grain of the Caledonian orogen, is marked by a distinct "2"0"6Pb/"2"0"7Pb isotope ratio anomaly. No clear regional or even local patterns are detected when mapping the Pb isotope ratios in the soil O horizon samples. Variation in the isotope ratios declines significantly from the soil C to the O horizon. On average, Pb concentrations in the O horizon are four times higher and the "2"0"6Pb/"2"0"7Pb isotope ratio is shifted towards a median of 1.15 in comparison to 1.27 in the C horizon. It is demonstrated that natural processes like weathering in combination with plant uptake need to be taken into account in order to distinguish anthropogenic input from natural influences on Pb concentration and the "2"0"6Pb/"2"0"7Pb isotope ratio in the soil O horizon. - Highlights: • Lead concentrations are on average higher by a factor of 4 in the soil O than in the C horizon. • The "2"0"6Pb/"2"0"7Pb isotope ratio is considerably lower in the soil O than in the C horizon. • The observed shifts are in conflict with exclusive anthropogenic input of Pb. • The hypothesis of natural Pb-isotope invariance can not be hold.

  20. Development of a Method to Isolate Glutamic Acid from Foodstuffs for a Precise Determination of Their Stable Carbon Isotope Ratio.

    Science.gov (United States)

    Kobayashi, Kazuhiro; Tanaka, Masaharu; Yatsukawa, Yoichi; Tanabe, Soichi; Tanaka, Mitsuru; Ohkouchi, Naohiko

    2018-01-01

    Recent growing health awareness is leading to increasingly conscious decisions by consumers regarding the production and traceability of food. Stable isotopic compositions provide useful information for tracing the origin of foodstuffs and processes of food production. Plants exhibit different ratios of stable carbon isotopes (δ 13 C) because they utilized different photosynthetic (carbon fixation) pathways and grow in various environments. The origins of glutamic acid in foodstuffs can be differentiated on the basis of these photosynthetic characteristics. Here, we have developed a method to isolate glutamic acid in foodstuffs for determining the δ 13 C value by elemental analyzer-isotope-ratio mass spectrometry (EA/IRMS) without unintended isotopic fractionation. Briefly, following acid-hydrolysis, samples were defatted and passed through activated carbon and a cation-exchange column. Then, glutamic acid was isolated using preparative HPLC. This method is applicable to measuring, with a low standard deviation, the δ 13 C values of glutamic acid from foodstuffs derived from C3 and C4 plants and marine algae.

  1. Sulfur isotopic ratios of molybdenites from the Hida Mountains, Japan

    International Nuclear Information System (INIS)

    Ishihara, Shunso; Harayama, Satoru; Sasaki, Akira.

    1990-01-01

    Molybdenites occurring in Paleogene granitoids of the Northern Japan Alps of the Hida Mountains were analyzed for δ 34 S CDT at seven localities. The sulfur isotopic ratios vary from 3.0 to 6.4 per mille, which are within the range of ore molybdenites from the magnetite-series granitic terrane of the Sanin district, indicating that the Hida Mountains and Sanin district belong to the same metallogenic province. Porphyry-type molybdenite from the Kamioka lead-zinc mine has the δ 34 S value of 1.4 per mille. Sulfur of the molybdenite is not derived from the Jurassic Funatsu granitoids but brought up by the latest Cretaceous ilmenite-series magma, prior to the main Paleogene magnetite-series magmatism. (author)

  2. Determination of isotope ratios of metals (and metalloids) by means of inductively coupled plasma-mass spectrometry for provenancing purposes - A review

    International Nuclear Information System (INIS)

    Balcaen, L.; Moens, L.; Vanhaecke, F.

    2010-01-01

    Since considerable time, isotopic analysis of different elements present in a sample, material or object (such as the 'light' elements H, C, N, O and S and 'heavy' elements, such as Sr and Pb), has been used in provenancing studies, as several factors - defined by 'the environment' or origin of the sample - can lead to measurable differences in their isotopic composition. For the light elements, traditionally, (gas source) isotope ratio mass spectrometry (IR-MS) is used, while for a long period of time, thermal ionization mass spectrometry (TIMS) was considered as the only technique capable of detecting subtle variations in the isotopic composition of the 'heavier' elements. However, since the introduction of the first inductively coupled plasma mass spectrometers (ICP-MS), considerable attention has been devoted to the development of methodologies and strategies to perform isotopic analysis by means of ICP-MS. While the relatively modest isotope ratio precision offered by single-collector ICP-MS may already be fit-for-purpose under some circumstances, especially the introduction of multi-collector ICP-MS instruments, equipped with an array of Faraday detectors instead of a single electron multiplier, has lead to tremendous improvements in the field of isotopic analysis. As a result, MC-ICP-MS can be seen as a very strong competitor of TIMS nowadays, while it even provides information on the small isotopic variations shown by some elements, that are not or hardly accessible by means of TIMS (e.g., elements with a high ionization energy). Owing to these new instrumental developments, the application field of isotopic analysis by means of ICP-MS is continuously growing, also in the field of provenance determination. This paper is intended as a review of the developments in and the recent applications of isotopic analysis by means of ICP-MS in this specific research field.

  3. The effect of exposure to employees from mining and milling operations in a uranium mine on lead isotopes--a pilot study.

    Science.gov (United States)

    Gulson, Brian L; Mizon, Karen J; Dickson, Bruce L; Korsch, Michael J

    2005-03-01

    Potential exposure during mining and milling of uranium ore has resulted in the industry being highly regulated. Exposure can arise from inhalation of the daughter product radioactive gas radon (222Rn), inhalation of radioactive dust particles from mining and milling, direct irradiation from outside the body, and ingestion of radionuclides (e.g. uranium or radium) in food or water. Making use of the highly unusual lead isotopic signature for uranium ores (high 206Pb/204Pb from the high uranium content, low 208Pb/204Pb from the low Th/U ratio), we undertook a pilot study of nine male mine employees and three controls from the Ranger uranium mine in the Northern Territory Australia to determine if it was feasible to use lead isotopes in blood to identify exposure to uranium-derived materials. The lead isotopic data for the mine employees and controls plot in two distinct fields which are consistent with predicted isotopic patterns. Assuming retention of 10% of the ingested lead, then the increases seen in 206Pb represent intakes of between 0.9 and 15 mg, integrated over the years of exposure. The small amount of lead does not affect blood lead concentrations, but appears to be sufficient to be detectable with sensitive isotopic methods. Further studies, including those on urine, should be undertaken to confirm the veracity of the lead isotope method in monitoring exposure of uranium industry employees.

  4. The effect of exposure to employees from mining and milling operations in a uranium mine on lead isotopes. A pilot study

    International Nuclear Information System (INIS)

    Gulson, Brian L.; Mizon, Karen J.; Dickson, Bruce L.; Korsch, Michael J.

    2005-01-01

    Potential exposure during mining and milling of uranium ore has resulted in the industry being highly regulated. Exposure can arise from inhalation of the daughter product radioactive gas radon ( 222 Rn), inhalation of radioactive dust particles from mining and milling, direct irradiation from outside the body, and ingestion of radionuclides (e.g. uranium or radium) in food or water. Making use of the highly unusual lead isotopic signature for uranium ores (high 206 Pb/ 204 Pb from the high uranium content, low 208 Pb/ 204 Pb from the low Th/U ratio), we undertook a pilot study of nine male mine employees and three controls from the Ranger uranium mine in the Northern Territory Australia to determine if it was feasible to use lead isotopes in blood to identify exposure to uranium-derived materials. The lead isotopic data for the mine employees and controls plot in two distinct fields which are consistent with predicted isotopic patterns. Assuming retention of 10% of the ingested lead, then the increases seen in 206 Pb represent intakes of between 0.9 and 15 mg, integrated over the years of exposure. The small amount of lead does not affect blood lead concentrations, but appears to be sufficient to be detectable with sensitive isotopic methods. Further studies, including those on urine, should be undertaken to confirm the veracity of the lead isotope method in monitoring exposure of uranium industry employees

  5. Isotope ratio mass spectrometry coupled to liquid and gas chromatography for wine ethanol characterization.

    Science.gov (United States)

    Cabañero, Ana I; Recio, Jose L; Rupérez, Mercedes

    2008-10-01

    Two new procedures for wine ethanol 13C/12C isotope ratio determination, using high-performance liquid chromatography and gas chromatography isotope ratio mass spectrometry (HPLC/IRMS and GC/IRMS), have been developed to improve isotopic methods dedicated to the study of wine authenticity. Parameters influencing separation of ethanol from wine matrix such as column, temperature, mobile phase, flow rates and injection mode were investigated. Twenty-three wine samples from various origins were analyzed for validation of the procedures. The analytical precision was better than 0.15 per thousand, and no significant isotopic fractionation was observed employing both separative techniques coupled to IRMS. No significant differences and a very strong correlation (r = 0.99) were observed between the 13C/12C ratios obtained by the official method (elemental analyzer/isotope ratio mass spectrometry) and the proposed new methodology. The potential advantages of the developed methods over the traditional one are speed (reducing time required from hours to minutes) and simplicity. In addition, these are the first isotopic methods that allow 13C/12C determination directly from a liquid sample with no previous ethanol isolation, overcoming technical difficulties associated with sample treatment.

  6. Application of ICP-MS and AMS for determination of Pu- and U-isotope ratios for source identification

    Energy Technology Data Exchange (ETDEWEB)

    Skipperud, L. (Norwegian Univ. of Life Sciences, Isotope Lab.. Dept. of Plant and Environmental Sciences, AAs (Norway))

    2010-03-15

    Full text: Anthropogenic plutonium has been introduced into the environment over the past 50 years as the result of the detonation of nuclear weapons and operational releases from the nuclear industry. In the Arctic environment, the main source of plutonium is from atmospheric weapons testing, which have resulted in a relatively uniform, underlying global distribution of plutonium. Plutonium isotope ratios are known to vary with reactor type, nuclear fuel-burn up time, neutron flux, and energy, and for fallout from nuclear detonations, weapon type and yield. Weapons-grade plutonium is characterized by a low content of the 240Pu isotope, with 240Pu/239Pu isotope ratio less than 0.05. In contrast, both global weapons fallout and spent nuclear fuel from civil reactors have higher 240Pu/239Pu isotope ratios (civil nuclear power reactors have 240Pu/239Pu atom ratios of between about 0.2-1). Thus, different sources often exhibit characteristic plutonium isotope ratios and these ratios can be used to identify the origin of contamination, calculate inventories, or follow the migration of contaminated sediments and waters. The measurement of the plutonium-isotope ratios in these studies offers both a means of identifying the origin of radionuclide contamination and the influence of the various nuclear installations on inputs to the Arctic, as well as a potential method for following the movement of water and sediment loads in the rivers. The present paper presents results from determination of plutonium concentrations and isotope ratios in sediment samples collected during various expeditions to the Kara Sea, the Ob and Yenisey estuaries and their river systems and also Pu isotope ratios in the near area of Mayak PA. Weapons-grade plutonium is characterized by a low content of the Pu-240 isotope, with Pu-240/Pu-239 isotope ratio less than 0.05. In contrast, both global weapons fallout and spent nuclear fuel from civil reactors have higher Pu-240/Pu-239 isotope ratios, and

  7. Direct uranium isotope ratio analysis of single micrometer-sized glass particles

    OpenAIRE

    Kappel, Stefanie; Boulyga, Sergei F.; Prohaska, Thomas

    2012-01-01

    We present the application of nanosecond laser ablation (LA) coupled to a ‘Nu Plasma HR’ multi collector inductively coupled plasma mass spectrometer (MC-ICP-MS) for the direct analysis of U isotope ratios in single, 10–20 μm-sized, U-doped glass particles. Method development included studies with respect to (1) external correction of the measured U isotope ratios in glass particles, (2) the applied laser ablation carrier gas (i.e. Ar versus He) and (3) the accurate determination of lower abu...

  8. Spatial distribution of lead and lead isotopes in soil B-horizon, forest-floor humus, grass (Avenella flexuosa) and spruce (Picea abies) needles across the Czech Republic

    Energy Technology Data Exchange (ETDEWEB)

    Sucharova, Julie; Suchara, Ivan [Silva Tarouca Research Institute for Landscape and Ornamental Gardening, Kvetnove namesti 391, 252 43 Pruhonice (Czech Republic); Reimann, Clemens, E-mail: Clemens.Reimann@ngu.no [Geological Survey of Norway, P.O. Box 6315 Sluppen, 7491 Trondheim (Norway); Boyd, Rognvald [Geological Survey of Norway, P.O. Box 6315 Sluppen, 7491 Trondheim (Norway); Filzmoser, Peter [Institute for Statistics and Probability Theory, Vienna University of Technology, Wiedner Hauptstrasse 8-10, 1040 Wien (Austria); Englmaier, Peter [Faculty of Life Science, University of Vienna, Althanstr. 14, A-1090 Vienna (Austria)

    2011-07-15

    Highlights: > Pb-concentrations and {sup 206}Pb/{sup 207}Pb isotope ratios are provided for four different sample materials for the Czech Republic. > The paper demonstrates the local impact of a number of different contamination sources. > The data provide clear evidence that traffic emissions are no major source of Pb to the Czech environment. > The data demonstrate that the B-horizon provides no valid 'background' for Pb-concentration or the {sup 206}Pb/{sup 207}Pb isotope ratio. > Pb isotope ratios change during soil weathering and at the interface biosphere/pedosphere. - Abstract: Lead concentrations were determined in samples of soil B-horizon (N = 258), forest-floor humus (O-horizon, N = 259), grass (Avenella flexuosa, N = 251) and spruce (Picea abies, N = 253) needles (2nd year) collected at the same locations evenly spread over the territory of the Czech Republic at an average density of 1 site/300 km{sup 2}. Median Pb concentrations differ widely in the four materials: soil B-horizon: 27 mg/kg (3.3-220 mg/kg), humus: 78 mg/kg (19-1863 mg/kg), grass: 0.37 mg/kg (0.08-8 mg/kg) and spruce needles: 0.23 mg/kg (0.07-3 mg/kg). In the Pb distribution maps for humus, grass and spruce a number of well-known Pb-contamination sources are indicated by unusually high concentrations (e.g., the Pb smelter at Pribram, the metallurgical industry in the NE of the Czech Republic and along the Polish border, as well as the metallurgical industry in Upper Silesia and Europe's largest coal-fired power plant at Bogatynia, Poland). The ratio {sup 206}Pb/{sup 207}Pb was determined in all four materials. The median value of the {sup 206}Pb/{sup 207}Pb isotope ratio in the soil B-horizon is 1.184 (variation: 1.145-1.337). In both humus and grass the median value for the {sup 206}Pb/{sup 207}Pb isotope ratio is 1.162 (variation: 1.130-1.182), in spruce needles the median ratio is 1.159 (variation: 1.116-1.186). In humus, grass and spruce needles the known contamination

  9. Origin of the mysterious Yin-Shang bronzes in China indicated by lead isotopes.

    Science.gov (United States)

    Sun, Wei-dong; Zhang, Li-peng; Guo, Jia; Li, Cong-ying; Jiang, Yu-hang; Zartman, Robert E; Zhang, Zhao-feng

    2016-03-18

    Fine Yin-Shang bronzes containing lead with puzzlingly highly radiogenic isotopic compositions appeared suddenly in the alluvial plain of the Yellow River around 1400 BC. The Tongkuangyu copper deposit in central China is known to have lead isotopic compositions even more radiogenic and scattered than those of the Yin-Shang bronzes. Most of the Yin-Shang bronzes are tin-copper alloys with high lead contents. The low lead and tin concentrations, together with the less radiogenic lead isotopes of bronzes in an ancient smelting site nearby, however, exclude Tongkuangyu as the sole supplier of the Yin-Shang bronzes. Interestingly, tin ingots/prills and bronzes found in Africa also have highly radiogenic lead isotopes, but it remains mysterious as to how such African bronzes may have been transported to China. Nevertheless, these African bronzes are the only bronzes outside China so far reported that have lead isotopes similar to those of the Yin-Shang bronzes. All these radiogenic lead isotopes plot along ~2.0-2.5 Ga isochron lines, implying that deposits around Archean cratons are the most likely candidates for the sources. African cratons along the Nile and even micro-cratons in the Sahara desert may have similar lead signatures. These places were probably accessible by ancient civilizations, and thus are the most favorable suppliers of the bronzes.

  10. Comparison of gas chromatography/isotope ratio mass spectrometry and liquid chromatography/isotope ratio mass spectrometry for carbon stable-isotope analysis of carbohydrates.

    Science.gov (United States)

    Moerdijk-Poortvliet, Tanja C W; Schierbeek, Henk; Houtekamer, Marco; van Engeland, Tom; Derrien, Delphine; Stal, Lucas J; Boschker, Henricus T S

    2015-07-15

    We compared gas chromatography/isotope ratio mass spectrometry (GC/IRMS) and liquid chromatography/isotope ratio mass spectrometry (LC/IRMS) for the measurement of δ(13)C values in carbohydrates. Contrary to GC/IRMS, no derivatisation is needed for LC/IRMS analysis of carbohydrates. Hence, although LC/IRMS is expected to be more accurate and precise, no direct comparison has been reported. GC/IRMS with the aldonitrile penta-acetate (ANPA) derivatisation method was compared with LC/IRMS without derivatisation. A large number of glucose standards and a variety of natural samples were analysed for five neutral carbohydrates at natural abundance as well as at (13)C-enriched levels. Gas chromatography/chemical ionisation mass spectrometry (GC/CIMS) was applied to check for incomplete derivatisation of the carbohydrate, which would impair the accuracy of the GC/IRMS method. The LC/IRMS technique provided excellent precision (±0.08‰ and ±3.1‰ at natural abundance and enrichment levels, respectively) for the glucose standards and this technique proved to be superior to GC/IRMS (±0.62‰ and ±19.8‰ at natural abundance and enrichment levels, respectively). For GC/IRMS measurements the derivatisation correction and the conversion of carbohydrates into CO2 had a considerable effect on the measured δ(13)C values. However, we did not find any significant differences in the accuracy of the two techniques over the full range of natural δ(13)C abundances and (13)C-labelled glucose. The difference in the performance of GC/IRMS and LC/IRMS diminished when the δ(13)C values were measured in natural samples, because the chromatographic performance and background correction became critical factors, particularly for LC/IRMS. The derivatisation of carbohydrates for the GC/IRMS method was complete. Although both LC/IRMS and GC/IRMS are reliable techniques for compound-specific stable carbon isotope analysis of carbohydrates (provided that derivatisation is complete and the

  11. Hydrogen and oxygen isotope ratios of geothermal waters in the southern hachimantai area

    International Nuclear Information System (INIS)

    Matsubaya, Osamu; Etchu, Hiroshi; Takenaka, Teruo; Yoshida, Yutaka.

    1985-01-01

    Geothermal waters from the Matsukawa and Kakkonda Geothermal Plants, wells at Amihari-Motoyu, and Nyuto and Tazawako areas were isotopically studied. The geothermal waters from Mutsukawa, Kakkonda and Amihari-Motoyu have hydrogen isotope ratios similar to the local meteoric waters, while have higher oxygen isotope ratios than the local meteoric waters. This relationship of hydrogen and oxygen isotope ratios, that is called ''oxygen shift'', means that these geothermal waters are meteoric waters undergone the oxygen isotope exchange with rocks at high temperature of underground. The exygen shifts are 2 -- 3 per mil in Matsukawa and Kakkonda, and 7 per mil in Amihari-Motoyu. This difference may be important to understand the processe of water-rock interaction in this area. The geothermal waters at Nyuto and Tazawako areas also show 2 -- 3 per mil oxygen shift. The steam from the Tazawako-cho well and the hot spring water form the Tsurunoyu are estimated to be vapor and liquid phases separated form a single geothermal water of NaCl type, though the hot water from the Tsurunoyu is diluted with shallow meteoric water. (author)

  12. Two-step extraction method for lead isotope fractionation to reveal anthropogenic lead pollution.

    Science.gov (United States)

    Katahira, Kenshi; Moriwaki, Hiroshi; Kamura, Kazuo; Yamazaki, Hideo

    2018-05-28

    This study developed the 2-step extraction method which eluted the Pb adsorbing on the surface of sediments in the first solution by aqua regia and extracted the Pb absorbed inside particles into the second solution by mixed acid of nitric acid, hydrofluoric acid and hydrogen peroxide solution. We applied the method to sediments in the enclosed water area and found out that the isotope ratios of Pb in the second solution represented those of natural origin. This advantage of the method makes it possible to distinguish the Pb between natural origin and anthropogenic source on the basis of the isotope ratios. The results showed that the method was useful to discuss the Pb sources and that anthropogenic Pb in the sediment samples analysed was mainly derived from China because of transboundary air pollution.

  13. Pb isotopes of Gorgona Island (Colombia): Isotopic variations correlated with magma type

    Energy Technology Data Exchange (ETDEWEB)

    Dupre, B.; Echeverria, L.M. (Max-Planck-Institut fuer Chemie (Otto-Hahn-Institut), Mainz (Germany, F.R.))

    1984-02-01

    Lead isotopic results obtained on komatiites and basalts from Gorgona Island provide evidence of large isotopic variations within a restricted area (8x2.5 km). The variations are correlated with differences in volcanic rock type. The highest isotopic ratios (/sup 206/Pb//sup 204/Pb proportional 19.75) correspond to tholeiites which make up most of the island. The lowest ratios (18.3) correspond to the komatiites of the west coast of the island.

  14. High precision isotopic ratio analysis of volatile metal chelates

    International Nuclear Information System (INIS)

    Hachey, D.L.; Blais, J.C.; Klein, P.D.

    1980-01-01

    High precision isotope ratio measurements have been made for a series of volatile alkaline earth and transition metal chelates using conventional GC/MS instrumentation. Electron ionization was used for alkaline earth chelates, whereas isobutane chemical ionization was used for transition metal studies. Natural isotopic abundances were determined for a series of Mg, Ca, Cr, Fe, Ni, Cu, Cd, and Zn chelates. Absolute accuracy ranged between 0.01 and 1.19 at. %. Absolute precision ranged between +-0.01-0.27 at. % (RSD +- 0.07-10.26%) for elements that contained as many as eight natural isotopes. Calibration curves were prepared using natural abundance metals and their enriched 50 Cr, 60 Ni, and 65 Cu isotopes covering the range 0.1-1010.7 at. % excess. A separate multiple isotope calibration curve was similarly prepared using enriched 60 Ni (0.02-2.15 at. % excess) and 62 Ni (0.23-18.5 at. % excess). The samples were analyzed by GC/CI/MS. Human plasma, containing enriched 26 Mg and 44 Ca, was analyzed by EI/MS. 1 figure, 5 tables

  15. Reproducibility of isotope ratio measurements

    International Nuclear Information System (INIS)

    Elmore, D.

    1981-01-01

    The use of an accelerator as part of a mass spectrometer has improved the sensitivity for measuring low levels of long-lived radionuclides by several orders of magnitude. However, the complexity of a large tandem accelerator and beam transport system has made it difficult to match the precision of low energy mass spectrometry. Although uncertainties for accelerator measured isotope ratios as low as 1% have been obtained under favorable conditions, most errors quoted in the literature for natural samples are in the 5 to 20% range. These errors are dominated by statistics and generally the reproducibility is unknown since the samples are only measured once

  16. Isotopic 32S/33S ratio as a diagnostic of presolar grains from novae

    Directory of Open Access Journals (Sweden)

    A. Parikh

    2014-10-01

    Full Text Available Measurements of sulphur isotopes in presolar grains can help to identify the astrophysical sites in which these grains were formed. A more precise thermonuclear rate of the 33S(p,γ34Cl reaction is required, however, to assess the diagnostic ability of sulphur isotopic ratios. We have studied the 33S(3He,d34Cl proton-transfer reaction at 25 MeV using a high-resolution quadrupole–dipole–dipole–dipole magnetic spectrograph. Deuteron spectra were measured at ten scattering angles between 10° and 55°. Twenty-four levels in 34Cl over Ex=4.6–5.9 MeV were observed, including three levels for the first time. Proton spectroscopic factors were extracted for the first time for levels above the 33S + p threshold, spanning the energy range required for calculations of the thermonuclear 33S(p,γ34Cl rate in classical nova explosions. We have determined a new 33S(p,γ34Cl rate using a Monte Carlo method and have performed new hydrodynamic nova simulations to determine the impact on nova nucleosynthesis of remaining nuclear physics uncertainties in the reaction rate. We find that these uncertainties lead to a factor of ≤5 variation in the 33S(p,γ34Cl rate over typical nova peak temperatures, and variation in the ejected nova yields of SCa isotopes by ≤20%. In particular, the predicted 32S/33S ratio is 110–130 for the nova model considered, compared to 110–440 with previous rate uncertainties. As recent type II supernova models predict ratios of 130–200, the 32S/33S ratio may be used to distinguish between grains of nova and supernova origin.

  17. A lead isotopic study of the human bioaccessibility of lead in urban soils from Glasgow, Scotland

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, John G., E-mail: J.G.Farmer@ed.ac.uk [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); Broadway, Andrew [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); Cave, Mark R.; Wragg, Joanna [British Geological Survey, Keyworth, Nottingham NG12 5GG, England (United Kingdom); Fordyce, Fiona M. [British Geological Survey, Edinburgh, EH9 3LA, Scotland (United Kingdom); Graham, Margaret C.; Ngwenya, Bryne T. [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); Bewley, Richard J.F. [URS Corporation Ltd, Manchester, M1 6HS, England (United Kingdom)

    2011-11-01

    The human bioaccessibility of lead (Pb) in Pb-contaminated soils from the Glasgow area was determined by the Unified Bioaccessibility Research Group of Europe (BARGE) Method (UBM), an in vitro physiologically based extraction scheme that mimics the chemical environment of the human gastrointestinal system and contains both stomach and intestine compartments. For 27 soils ranging in total Pb concentration from 126 to 2160 mg kg{sup -1} (median 539 mg kg{sup -1}), bioaccessibility as determined by the 'stomach' simulation (pH {approx} 1.5) was 46-1580 mg kg{sup -1}, equivalent to 23-77% (mean 52%) of soil total Pb concentration. The corresponding bioaccessibility data for the 'stomach + intestine' simulation (pH {approx} 6.3) were 6-623 mg kg{sup -1} and 2-42% (mean 22%) of soil Pb concentration. The soil {sup 206}Pb/{sup 207}Pb ratios ranged from 1.057 to 1.175. Three-isotope plots of {sup 208}Pb/{sup 206}Pb against {sup 206}Pb/{sup 207}Pb demonstrated that {sup 206}Pb/{sup 207}Pb ratios were intermediate between values for source end-member extremes of imported Australian Pb ore (1.04) - used in the manufacture of alkyl Pb compounds (1.06-1.10) formerly added to petrol - and indigenous Pb ores/coal (1.17-1.19). The {sup 206}Pb/{sup 207}Pb ratios of the UBM 'stomach' extracts were similar (< 0.01 difference) to those of the soil for 26 of the 27 samples (r = 0.993, p < 0.001) and lower in 24 of them. A slight preference for lower {sup 206}Pb/{sup 207}Pb ratio was discernible in the UBM. However, the source of Pb appeared to be less important in determining the extent of UBM-bioaccessible Pb than the overall soil total Pb concentration and the soil phases with which the Pb was associated. The significant phases identified in a subset of samples were carbonates, manganese oxides, iron-aluminium oxyhydroxides and clays. - Highlights: {yields} We determined the human bioaccessibility of Pb in urban soils by in vitro extraction. {yields} We

  18. Changes in hydrogen isotope ratios in sequential plumage stages: an implication for the creation of isotope-base maps for tracking migratory birds.

    Science.gov (United States)

    Duxbury, J M; Holroyd, G L; Muehlenbachs, K

    2003-09-01

    Accurate reference maps are important in the use of stable-isotopes to track the movements of migratory birds. Reference maps created by the analysis of samples collected from young at the nest site are more accurate than simply referring to naturally occurring patterns of hydrogen isotope ratios created by precipitation cycles. Ratios of hydrogen isotopes in the nutrients incorporated early in the development of young birds can be derived from endogenous, maternal sources. Base-maps should be created with the analysis of tissue samples from hatchlings after local the isotopic signature of exogenous nutrients is dominant. Migratory species such as Peregrine Falcons are known to use endogenous sources in the creation of their eggs, therefore knowledge of what plumage stage best represents the local hydrogen ratios would assist in the planning of nest visits. We conducted diet manipulation experiments involving Japanese Quail and Peregrine Falcons to determine the plumage stage when hydrogen isotope ratios were indicative of a switch in their food source. The natal down of both the quail and falcons reflected the diet of breeding adult females. The hydrogen isotope ratios of a new food source were dominant in the juvenile down of the young falcons, although a further shift was detected in the final juvenile plumage. The juvenile plumage is grown during weeks 3-4 after hatch on Peregrine Falcons. Nest visits for the purpose of collecting feathers for isotope-base-map creation should be made around 4 weeks after the presumed hatch of the young falcons.

  19. Evaluation strategies for isotope ratio measurements of single particles by LA-MC-ICPMS.

    Science.gov (United States)

    Kappel, S; Boulyga, S F; Dorta, L; Günther, D; Hattendorf, B; Koffler, D; Laaha, G; Leisch, F; Prohaska, T

    2013-03-01

    Data evaluation is a crucial step when it comes to the determination of accurate and precise isotope ratios computed from transient signals measured by multi-collector-inductively coupled plasma mass spectrometry (MC-ICPMS) coupled to, for example, laser ablation (LA). In the present study, the applicability of different data evaluation strategies (i.e. 'point-by-point', 'integration' and 'linear regression slope' method) for the computation of (235)U/(238)U isotope ratios measured in single particles by LA-MC-ICPMS was investigated. The analyzed uranium oxide particles (i.e. 9073-01-B, CRM U010 and NUSIMEP-7 test samples), having sizes down to the sub-micrometre range, are certified with respect to their (235)U/(238)U isotopic signature, which enabled evaluation of the applied strategies with respect to precision and accuracy. The different strategies were also compared with respect to their expanded uncertainties. Even though the 'point-by-point' method proved to be superior, the other methods are advantageous, as they take weighted signal intensities into account. For the first time, the use of a 'finite mixture model' is presented for the determination of an unknown number of different U isotopic compositions of single particles present on the same planchet. The model uses an algorithm that determines the number of isotopic signatures by attributing individual data points to computed clusters. The (235)U/(238)U isotope ratios are then determined by means of the slopes of linear regressions estimated for each cluster. The model was successfully applied for the accurate determination of different (235)U/(238)U isotope ratios of particles deposited on the NUSIMEP-7 test samples.

  20. Influences of large-scale convection and moisture source on monthly precipitation isotope ratios observed in Thailand, Southeast Asia

    Science.gov (United States)

    Wei, Zhongwang; Lee, Xuhui; Liu, Zhongfang; Seeboonruang, Uma; Koike, Masahiro; Yoshimura, Kei

    2018-04-01

    Many paleoclimatic records in Southeast Asia rely on rainfall isotope ratios as proxies for past hydroclimatic variability. However, the physical processes controlling modern rainfall isotopic behaviors in the region is poorly constrained. Here, we combined isotopic measurements at six sites across Thailand with an isotope-incorporated atmospheric circulation model (IsoGSM) and the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model to investigate the factors that govern the variability of precipitation isotope ratios in this region. Results show that rainfall isotope ratios are both correlated with local rainfall amount and regional outgoing longwave radiation, suggesting that rainfall isotope ratios in this region are controlled not only by local rain amount (amount effect) but also by large-scale convection. As a transition zone between the Indian monsoon and the western North Pacific monsoon, the spatial difference of observed precipitation isotope among different sites are associated with moisture source. These results highlight the importance of regional processes in determining rainfall isotope ratios in the tropics and provide constraints on the interpretation of paleo-precipitation isotope records in the context of regional climate dynamics.

  1. Impacts of aerosol lead to natural ecosystems

    International Nuclear Information System (INIS)

    Murozumi, Masayo; Nakamura, Seiji; Yoshida, Katsumi

    1982-01-01

    Impacts of aerosol lead have changed the concentration and isotopic ratios of the element circulating in remote ecosystems in the Hidaka and Tarumae mountains. Concentrations of lead in successive each 10 years ring veneer of Cercidiphyllum Japonica show that amount of the element residing on the bark and supwood layers has increased by a factor of 2 or more in comparison with that of the core part. The isotopic ratios of lead in the basement rocks and soils under the ecosystems converge to a certain narrow spot along the isochron Iine of the element, and distinguish their geochronogical characteristics from other leads of different sources. In these ecosystems, however, the lead isotopic ratios of materials exposed to the atmosphere are similar to those of foreign and anthropogenic aerosol lead but are evidently dissimilar to those of the rocks and soils. Furthermore, the lead isotopic ratios in yearly ring veneers of Ceridiphyllum Japonica and Ostrya Japonica show a certain differentiation towards the bark from the core, i.e., an approach to those of anthropogenic aerosol lead from those of the basement rocks and soils, as listed in Table 7. The lead burden per hectare in these remote ecosystems has increased to 4 g by the impact of 2 g of aerosol lead. (author)

  2. Lead isotope ratios in six lake sediment cores from Japan Archipelago: Historical record of trans-boundary pollution sources.

    Science.gov (United States)

    Hosono, Takahiro; Alvarez, Kelly; Kuwae, Michinobu

    2016-07-15

    Sediment cores from six lakes situated from north to south on the Japanese Archipelago were collected during 2009-2010 to investigate the hypothesis that deposition of lead (Pb) was coming from East Asia (including China, South Korea and eastern part of Russia). Accumulation rates and ages of the lake sediment were estimated by the (210)Pb constant rate of supply model and (137)Cs inputs to reconstruct the historical trends of Pb accumulation. Cores from four lakes located in the north and central Japan, showed clear evidence of Pb pollution with a change in the (206)Pb/(207)Pb and (208)Pb/(207)Pb ratios in the recent sediment as compared to the deeper sediment. Among the six studied lakes, significant inputs of anthropogenic lead emissions were observed at Lake Mikazuki (north Hokkaido in north Japan), Lake Chokai (north of Honshu), and Lake Mikuriga (central part of Honshu). Pb isotopic comparison of collected core sediment and previously reported data for wet precipitation and aerosols from different Asian regions indicate that, before 1900, Pb accumulated in these three lakes was not affected by trans-boundary sources. Lake Mikazuki started to receive Pb emissions from Russia in early 1900s, and during the last two decades, this lake has been affected by trans-boundary Pb pollution from northern China. Lake Chokai has received Pb pollutant from northern China since early 1900s until 2009, whereas for the Lake Mikuriga the major Pb contaminant was transported from southern China during the past 100years. The results of our study demonstrate that Japan Archipelago has received trans-boundary Pb emissions from different parts of East Asian region depending on location, and the major source region has changed historically. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Lead Isotopic Compositions of Selected Coals, Pb/Zn Ores and Fuels in China and the Application for Source Tracing.

    Science.gov (United States)

    Bi, Xiang-Yang; Li, Zhong-Gen; Wang, Shu-Xiao; Zhang, Lei; Xu, Rui; Liu, Jin-Ling; Yang, Hong-Mei; Guo, Ming-Zhi

    2017-11-21

    Lead (Pb) pollution emission from China is becoming a potential worldwide threat. Pb isotopic composition analysis is a useful tool to accurately trace the Pb sources of aerosols in atmosphere. In this study, a comprehensive data set of Pb isotopes for coals, Pb/Zn ores, and fuels from China was presented. The ratios of 206 Pb/ 207 Pb and 208 Pb/ 206 Pb in the coals were in the range of 1.114-1.383 and 1.791-2.317, similar to those from Europe, Oceania, and South Asia, but different from those from America (p fuels from in coals. Urban aerosols demonstrated similar Pb isotopic compositions to coals, Pb/Zn ores, and fuels in China. After removing the leaded gasoline, the Pb in aerosols is more radiogenic, supporting the heavy contribution of coal combustion to the atmospheric Pb pollution.

  4. Total contribution of airborne lead to blood lead.

    OpenAIRE

    Manton, W I

    1985-01-01

    A nine year study of blood lead concentrations and isotope ratios carried out on a married couple shows that pulmonary deposition cannot account for all the airborne lead in blood; that lead from bone may comprise 70% of blood lead; and that during pregnancy blood lead may double due to mobilisation of lead from bone.

  5. Fractionation in position-specific isotope composition during vaporization of environmental pollutants measured with isotope ratio monitoring by 13C nuclear magnetic resonance spectrometry

    International Nuclear Information System (INIS)

    Julien, Maxime; Parinet, Julien; Nun, Pierrick; Bayle, Kevin; Höhener, Patrick; Robins, Richard J.; Remaud, Gérald S.

    2015-01-01

    Isotopic fractionation of pollutants in terrestrial or aqueous environments is a well-recognized means by which to track different processes during remediation. As a complement to the common practice of measuring the change in isotope ratio for the whole molecule using isotope ratio monitoring by mass spectrometry (irm-MS), position-specific isotope analysis (PSIA) can provide further information that can be exploited to investigate source and remediation of soil and water pollutants. Position-specific fractionation originates from either degradative or partitioning processes. We show that isotope ratio monitoring by 13 C NMR (irm- 13 C NMR) spectrometry can be effectively applied to methyl tert-butylether, toluene, ethanol and trichloroethene to obtain this position-specific data for partitioning. It is found that each compound exhibits characteristic position-specific isotope fractionation patterns, and that these are modulated by the type of evaporative process occurring. Such data should help refine models of how remediation is taking place, hence back-tracking to identify pollutant sources. - Highlights: • Position-Specific Isotope Analysis (PSIA) by 13 C NMR spectrometry. • PSIA on isotope fractionation during several vaporization processes. • PSIA for isotope profiling in environment pollutants. • Intramolecular 13 C reveal normal and inverse effects, bulk values being unchanged. - PSIA in pollutants during evaporation processes shows more detailed information for discerning the nature of the process involved than does bulk isotope measurements

  6. Absolute measurement of the isotopic ratio of a water sample with very low deuterium content

    International Nuclear Information System (INIS)

    Hagemann, R.; Nief, G.; Roth, E.

    1968-01-01

    The presence of H 3+ ions which are indistinguishable from HD + ions presents the principal difficulty encountered in the measurement of isotopic ratios of water samples with very low deuterium contents using a mass spectrometer. Thus, when the sample contains no deuterium, the mass spectrometer does not indicate zero. By producing, in situ, from the sample to be measured, water vapor with an isotopic ratio very close to zero using a small distilling column, this difficulty is overcome. This column, its operating parameters, as well as the way in which the measurements are made are described. An arrangement is employed in which the isotopic ratios can be measured with a sensitivity better than 0.01 x 10 -6 . The method is applied to the determination of the isotopic ratios of three low deuterium content water samples. The results obtained permit one to assign to the sample with the lowest deuterium content an absolute value equal to 1.71 ± 0.03 ppm. This water sample is a primary standard from which is determined the isotopic ratio of a natural water sample which serves as the laboratory standard. (author) [fr

  7. Lead as a pathfinder for uranium mineralization

    International Nuclear Information System (INIS)

    Shouls, M.M.

    1983-01-01

    The theoretical aspects of the formation of radiogenic lead anomalies from uranium and thorium mineralization are discussed in the light of differing mobilities of the parent elements and the stable lead daughter. It is concluded that recognizable lead anomalies can persist in the weathered tops of ancient uranium deposits, and such anomalies can be identified from the stable lead isotope ratios. In addition, with mixed U-Th mineralization lead isotopic ratios may be identified after most of the uranium has been leached away. The theoretical models also include possible additions of entrained lead with the mineralization and its effects on the isotopic ratios. This reasoning was tested in the evaluation of a radiometric anomaly in northern Malawi where a discrepancy between the U and eU values suggested a uranium-depleted mixed U-Th deposit. However, the partly coincident lead anomaly did not fit the isotope models proposed in the first part of the paper, and they indicated an unexpectedly young age. The anomaly was therefore downgraded but the adequacy of the theory was not tested. (author)

  8. Surface dust wipes are the best predictors of blood leads in young children with elevated blood lead levels

    Energy Technology Data Exchange (ETDEWEB)

    Gulson, Brian, E-mail: brian.gulson@mq.edu.au [Graduate School of the Environment, Macquarie University, North Ryde NSW 2109 (Australia); CSIRO Earth Science and Resource Engineering, North Ryde NSW 2113 (Australia); Anderson, Phil [Information and Statistics Group, Australian Institute of Health and Welfare, Canberra ACT 2601 (Australia); Faculty of Health, University of Canberra, Canberra ACT 2601 (Australia); Taylor, Alan [Department of Psychology, Macquarie University, Sydney NSW 2109 (Australia)

    2013-10-15

    Background: As part of the only national survey of lead in Australian children, which was undertaken in 1996, lead isotopic and lead concentration measurements were obtained from children from 24 dwellings whose blood lead levels were ≥15 µg/dL in an attempt to determine the source(s) of their elevated blood lead. Comparisons were made with data for six children with lower blood lead levels (<10 µg/dL). Methods: Thermal ionisation and isotope dilution mass spectrometry were used to determine high precision lead isotopic ratios ({sup 208}Pb/{sup 206}Pb, {sup 207}Pb/{sup 206}Pb and {sup 206}Pb/{sup 204}Pb) and lead concentrations in blood, dust from floor wipes, soil, drinking water and paint (where available). Evaluation of associations between blood and the environmental samples was based on the analysis of individual cases, and Pearson correlations and multiple regression analyses based on the whole dataset. Results and discussion: The correlations showed an association for isotopic ratios in blood and wipes (r=0.52, 95% CI 0.19–0.74), blood and soil (r=0.33, 95% CI −0.05–0.62), and blood and paint (r=0.56, 95% CI 0.09–0.83). The regression analyses indicated that the only statistically significant relationship for blood isotopic ratios was with dust wipes (B=0.65, 95% CI 0.35–0.95); there were no significant associations for lead concentrations in blood and environmental samples. There is a strong isotopic correlation of soils and house dust (r=0.53, 95% CI 0.20–0.75) indicative of a common source(s) for lead in soil and house dust. In contrast, as with the regression analyses, no such association is present for bulk lead concentrations (r=−0.003, 95% CI −0.37–0.36), the most common approach employed in source investigations. In evaluation of the isotopic results on a case by case basis, the strongest associations were for dust wipes and blood. -- Highlights: • Children with elevated blood lead ≥15 µg/dL compared with a group with <10

  9. Hafnium isotope ratios of nine GSJ reference samples

    International Nuclear Information System (INIS)

    Hanyu, Takeshi; Nakai, Shun'ichi; Tatsuta, Riichiro

    2005-01-01

    176 Hf/ 177 Hf ratios of nine geochemical reference rocks from the Geological Survey of Japan, together with BIR-1 and BCR-2, were determined using multi-collector inductively coupled plasma mass spectrometry. Our data for BIR-1, BCR-2 and JB-1 are in agreement with those previously reported, demonstrating the appropriateness of the chemical procedure and isotopic measurement employed in this study. The reference rocks have a wide range of 176 Hf/ 177 Hf covering the field defined by various volcanic rocks, such as mid-ocean ridge basalts, ocean island basalts, and subduction related volcanic rocks. They are therefore suitable as rock standards for Hf isotope measurement of geological samples. (author)

  10. Plutonium isotopes/137Cs activity ratios for soil in Montenegro

    International Nuclear Information System (INIS)

    Antovic, N. M.; Vukotic, P.; Svrkota, N.; Andrukhovich, S.K.

    2011-01-01

    Plutonium isotopes/ 137 Cs activity ratios were determined for six soil samples from Montenegro, using the results of alpha-spectrometric measurements of 239+240 Pu and 238 Pu, as well as gamma-spectrometric cesium measurements. An average 239+240 Pu/ 137 Cs activity ratio is found to be 0.02, as the 238 Pu/ 137 Cs and 238 Pu/ 239+240 Pu one - 0.0006 and 0.03, respectively. It follows from the results that the source of plutonium in Montenegro soil is nuclear weapon testing during the fifties and sixties of the twentieth century. On the other hand, there is a contribution of the accident at the Chernobyl nuclear power plant to the soil contamination with 137 Cs isotope. [sr

  11. Total contribution of airborne lead to blood lead.

    Science.gov (United States)

    Manton, W I

    1985-01-01

    A nine year study of blood lead concentrations and isotope ratios carried out on a married couple shows that pulmonary deposition cannot account for all the airborne lead in blood; that lead from bone may comprise 70% of blood lead; and that during pregnancy blood lead may double due to mobilisation of lead from bone. PMID:3970881

  12. On the interference of Kr during carbon isotope analysis of methane using continuous-flow combustion–isotope ratio mass spectrometry

    NARCIS (Netherlands)

    Schmitt, J.; Seth, B.; Bock, M; van der Veen, C.; Möller, L.; Sapart, C.J.; Prokopiou, M.; Sowers, T.; Röckmann, T.; Fischer, H

    2013-01-01

    Stable carbon isotope analysis of methane ( 13C of CH4) on atmospheric samples is one key method to constrain the current and past atmospheric CH4 budget. A frequently applied measurement technique is gas chromatography (GC) isotope ratio mass spectrometry (IRMS) coupled to a

  13. Preliminary results of oxygen isotope ratio measurement with a particle-gamma coincidence method

    Energy Technology Data Exchange (ETDEWEB)

    Borysiuk, Maciek, E-mail: maciek.borysiuk@pixe.lth.se; Kristiansson, Per; Ros, Linus; Abdel, Nassem S.; Elfman, Mikael; Nilsson, Charlotta; Pallon, Jan

    2015-04-01

    The possibility to study variations in the oxygen isotopic ratio with photon tagged nuclear reaction analysis (pNRA) is evaluated in the current work. The experiment described in the article was performed at Lund Ion Beam Analysis Facility (LIBAF) with a 2 MeV deuteron beam. Isotopic fractionation of light elements such as carbon, oxygen and nitrogen is the basis of many analytical tools in hydrology, geology, paleobiology and paleogeology. IBA methods provide one possible tool for measurement of isotopic content. During this experimental run we focused on measurement of the oxygen isotopic ratio. The measurement of stable isotopes of oxygen has a number of applications; the particular one driving the current investigation belongs to the field of astrogeology and specifically evaluation of fossil extraterrestrial material. There are three stable isotopes of oxygen: {sup 16}O, {sup 17}O and {sup 18}O. We procured samples highly enriched with all three isotopes. Isotopes {sup 16}O and {sup 18}O were easily detected in the enriched samples, but no significant signal from {sup 17}O was detected in the same samples. The measured yield was too low to detect {sup 18}O in a sample with natural abundances of oxygen isotopes, at least in the current experimental setup, but the spectral line from the reaction with {sup 16}O was clearly visible.

  14. Chlorine isotope effects from isotope ratio mass spectrometry suggest intramolecular C-Cl bond competition in trichloroethene (TCE) reductive dehalogenation.

    Science.gov (United States)

    Cretnik, Stefan; Bernstein, Anat; Shouakar-Stash, Orfan; Löffler, Frank; Elsner, Martin

    2014-05-20

    Chlorinated ethenes are prevalent groundwater contaminants. To better constrain (bio)chemical reaction mechanisms of reductive dechlorination, the position-specificity of reductive trichloroethene (TCE) dehalogenation was investigated. Selective biotransformation reactions (i) of tetrachloroethene (PCE) to TCE in cultures of Desulfitobacterium sp. strain Viet1; and (ii) of TCE to cis-1,2-dichloroethene (cis-DCE) in cultures of Geobacter lovleyi strain SZ were investigated. Compound-average carbon isotope effects were -19.0‰ ± 0.9‰ (PCE) and -12.2‰ ± 1.0‰ (TCE) (95% confidence intervals). Using instrumental advances in chlorine isotope analysis by continuous flow isotope ratio mass spectrometry, compound-average chorine isotope effects were measured for PCE (-5.0‰ ± 0.1‰) and TCE (-3.6‰ ± 0.2‰). In addition, position-specific kinetic chlorine isotope effects were determined from fits of reactant and product isotope ratios. In PCE biodegradation, primary chlorine isotope effects were substantially larger (by -16.3‰ ± 1.4‰ (standard error)) than secondary. In TCE biodegradation, in contrast, the product cis-DCE reflected an average isotope effect of -2.4‰ ± 0.3‰ and the product chloride an isotope effect of -6.5‰ ± 2.5‰, in the original positions of TCE from which the products were formed (95% confidence intervals). A greater difference would be expected for a position-specific reaction (chloride would exclusively reflect a primary isotope effect). These results therefore suggest that both vicinal chlorine substituents of TCE were reactive (intramolecular competition). This finding puts new constraints on mechanistic scenarios and favours either nucleophilic addition by Co(I) or single electron transfer as reductive dehalogenation mechanisms.

  15. Applications of Isotope Ratio Mass Spectrometry in Sports Drug Testing Accounting for Isotope Fractionation in Analysis of Biological Samples.

    Science.gov (United States)

    Piper, Thomas; Thevis, Mario

    2017-01-01

    The misuse of anabolic-androgenic steroids (AAS) in sports aiming at enhancing athletic performance has been a challenging matter for doping control laboratories for decades. While the presence of a xenobiotic AAS or its metabolite(s) in human urine immediately represents an antidoping rule violation, the detection of the misuse of endogenous steroids such as testosterone necessitates comparably complex procedures. Concentration thresholds and diagnostic analyte ratios computed from urinary steroid concentrations of, e.g., testosterone and epitestosterone have aided identifying suspicious doping control samples in the past. These ratios can however also be affected by confounding factors and are therefore not sufficient to prove illicit steroid administrations. Here, carbon and, in rare cases, hydrogen isotope ratio mass spectrometry (IRMS) has become an indispensable tool. Importantly, the isotopic signatures of pharmaceutical steroid preparations commonly differ slightly but significantly from those found with endogenously produced steroids. By comparing the isotope ratios of endogenous reference compounds like pregnanediol to that of testosterone and its metabolites, the unambiguous identification of the urinary steroids' origin is accomplished. Due to the complex urinary matrix, several steps in sample preparation are inevitable as pure analyte peaks are a prerequisite for valid IRMS determinations. The sample cleanup encompasses steps such as solid phase or liquid-liquid extraction that are presumably not accompanied by isotopic fractionation processes, as well as more critical steps like enzymatic hydrolysis, high-performance liquid chromatography fractionation, and derivatization of analytes. In order to exclude any bias of the analytical results, each step of the analytical procedure is optimized and validated to exclude, or at least result in constant, isotopic fractionation. These efforts are explained in detail. © 2017 Elsevier Inc. All rights reserved.

  16. Oxygen isotope ratios of the Icelandic crust

    International Nuclear Information System (INIS)

    Hattori, K.; Muehlenbachs, K.

    1982-01-01

    Oxygen isotope ratios of hydrothermally altered basalts from depth of up to approx.3 km are reported from three localities in Iceland: International Research Drilling Project (IRDP) core at Reydarfjordur, eastern Iceland (Tertiary age); drill cuttings from Reykjavik (Plio-Pleistocene age); and Halocene drill cuttings from the active Krafla central volcano. Whole rock samples from these three localities have delta 18 O values averaging +3.9 +- 1.3, +2.4 +- 1.1, and -7.7 +- 2.4%, respectively. The observed values in the deeper samples from Krafla are as low as the values for any rocks previously reported. There seems to be a slight negative gradient in delta 18 O with depth at the former two localities and a more pronounced one at Krafla. Oxygen isotope fractionations between epidote and quartz and those between calcite and fluid suggests that the basalts were altered at temperatures of 300 0 --400 0 C. Low deltaD and delta 18 O of epidote and low delta 34 S of anhydrite indicate that the altering fluids in all three areas originated as meteoric waters and have undergone varied 'oxygen shifts'. Differences in the 18 O shift of the fluids are attributed to differences in hydrothermal systems; low water/rock ratios ( 5) at Krafla. The convective hydrothermal activity, which is probably driven by silicic magma beneath the central volcanoes, has caused strong subsolidus depletion of 18 O in the rocks. The primary-magnetic delta 18 O value of the rocks in the Tertiary IRDP core was about +3.9%, which is lower than that obtained for fresh basalt from other places. Such exceptionally low delta 18 O magmas are common in Iceland and may occur as the result of oxygen isotope exchange with or assimilation of altered rocks that form a thick sequence beneath the island due to isostatic subsidence

  17. Continuous-flow isotope ratio mass spectrometry method for carbon and hydrogen isotope measurements on atmospheric methane

    Directory of Open Access Journals (Sweden)

    M. Brass

    2010-12-01

    Full Text Available We describe a continuous-flow isotope ratio mass spectrometry (CF-IRMS technique for high-precision δD and δ13C measurements of atmospheric methane on 40 mL air samples. CH4 is separated from other air components by utilizing purely physical processes based on temperature, time and mechanical valve switching. Chemical agents are avoided. Trace amounts of interfering compounds can be separated by gas chromatography after pre-concentration of the CH4 sample. The purified sample is then either combusted to CO2 or pyrolyzed to H2 for stable isotope measurement. Apart from connecting samples and refilling liquid nitrogen as coolant the system is fully automated and allows an unobserved, continuous analysis of samples. The analytical system has been used for analysis of air samples with CH4 mixing ratios between ~100 and ~10 000 ppb, for higher mixing ratios samples usually have to be diluted.

  18. Determination of Light Water Reactor Fuel Burnup with the Isotope Ratio Method

    International Nuclear Information System (INIS)

    Gerlach, David C.; Mitchell, Mark R.; Reid, Bruce D.; Gesh, Christopher J.; Hurley, David E.

    2007-01-01

    For the current project to demonstrate that isotope ratio measurements can be extended to zirconium alloys used in LWR fuel assemblies we report new analyses on irradiated samples obtained from a reactor. Zirconium alloys are used for structural elements of fuel assemblies and for the fuel element cladding. This report covers new measurements done on irradiated and unirradiated zirconium alloys, Unirradiated zircaloy samples serve as reference samples and indicate starting values or natural values for the Ti isotope ratio measured. New measurements of irradiated samples include results for 3 samples provided by AREVA. New results indicate: 1. Titanium isotope ratios were measured again in unirradiated samples to obtain reference or starting values at the same time irradiated samples were analyzed. In particular, 49Ti/48Ti ratios were indistinguishably close to values determined several months earlier and to expected natural values. 2. 49Ti/48Ti ratios were measured in 3 irradiated samples thus far, and demonstrate marked departures from natural or initial ratios, well beyond analytical uncertainty, and the ratios vary with reported fluence values. The irradiated samples appear to have significant surface contamination or radiation damage which required more time for SIMS analyses. 3. Other activated impurity elements still limit the sample size for SIMS analysis of irradiated samples. The sub-samples chosen for SIMS analysis, although smaller than optimal, were still analyzed successfully without violating the conditions of the applicable Radiological Work Permit

  19. Applications of compound-specific carbon isotope ratios in organic contaminant studies

    International Nuclear Information System (INIS)

    Aravena, R.; Hunkeler, D.; Bloom, Y.; Frape, S.K.; Butler, B.; Edwards, E.; Cox, E.

    1999-01-01

    In this paper results are presented on the application of compound-specific isotope ratios measurements to assess biodegradation of chlorinated solvents, in particularly on microbial dechlorination of tetrachloroethene (PCE) and trichloroethene (TCE). Analytical aspects and isotope data from laboratory and field studies are discussed. The analytical tests showed that both headspace and SPME techniques provide accurate δ 13 C values with a similar precision for a wide range of chlorinated solvents. However, the SPME method is generally more sensitive. The microcosm experiments show that a significant isotopic fractionation occurs during dechlorination of PCE and TCE to ethene. The largest fractionation factors are observed in the steps DCE-VC and VC-Ethene. In general, the δ 13 C of each dechlorination product was always more negative than the δ 13 C of the corresponding precursor. In addition, the δ 13 C values of each compound increased with time. A similar pattern was observed for dechlorination of PCE at a field site. These results show that compound-specific carbon isotope ratios technology is a very sensitive tool for evaluation of natural attenuation of chlorinated solvents in groundwater. (author)

  20. Forensic analysis of explosives using isotope ratio mass spectrometry (IRMS)--part 1: instrument validation of the DELTAplusXP IRMS for bulk nitrogen isotope ratio measurements.

    Science.gov (United States)

    Benson, Sarah J; Lennard, Christopher J; Hill, David M; Maynard, Philip; Roux, Claude

    2010-01-01

    A significant amount of research has been conducted into the use of stable isotopes to assist in determining the origin of various materials. The research conducted in the forensic field shows the potential of isotope ratio mass spectrometry (IRMS) to provide a level of discrimination not achievable utilizing traditional forensic techniques. Despite the research there have been few, if any, publications addressing the validation and measurement uncertainty of the technique for forensic applications. This study, the first in a planned series, presents validation data for the measurement of bulk nitrogen isotope ratios in ammonium nitrate (AN) using the DELTA(plus)XP (Thermo Finnigan) IRMS instrument equipped with a ConFlo III interface and FlashEA 1112 elemental analyzer (EA). Appropriate laboratory standards, analytical methods and correction calculations were developed and evaluated. A validation protocol was developed in line with the guidelines provided by the National Association of Testing Authorities, Australia (NATA). Performance characteristics including: accuracy, precision/repeatability, reproducibility/ruggedness, robustness, linear range, and measurement uncertainty were evaluated for the measurement of nitrogen isotope ratios in AN. AN (99.5%) and ammonium thiocyanate (99.99+%) were determined to be the most suitable laboratory standards and were calibrated against international standards (certified reference materials). All performance characteristics were within an acceptable range when potential uncertainties, including the manufacturer's uncertainty of the technique and standards, were taken into account. The experiments described in this article could be used as a model for validation of other instruments for similar purposes. Later studies in this series will address the more general issue of demonstrating that the IRMS technique is scientifically sound and fit-for-purpose in the forensic explosives analysis field.

  1. Tracing contamination sources in soils with Cu and Zn isotopic ratios

    Energy Technology Data Exchange (ETDEWEB)

    Fekiacova, Z.; Cornu, S. [INRA, UR 1119 Géochimie des Sols et des Eaux, F-13100 Aix en Provence (France); Pichat, S. [Laboratoire de Géologie de Lyon (LGL-TPE), Ecole Normale Supérieure de Lyon, CNRS, UMR 5276, 69007 Lyon (France)

    2015-06-01

    Copper (Cu) and zinc (Zn) are naturally present and ubiquitous in soils and are important micronutrients. Human activities contribute to the input of these metals to soils in different chemical forms, which can sometimes reach a toxic level for soil organisms and plants. Isotopic signatures could be used to trace sources of anthropogenic Cu and Zn pollution. The aim of this paper is to determine whether it is possible to identify (i) Cu and Zn contamination in soils and their sources, on the basis of their isotopic signatures, and (ii) situations that are a priori favorable or not for tracing Cu and Zn pollution using the isotopic approach. Therefore, we compiled data from the literature on Cu and Zn isotopes in soils, rocks and pollutants and added to this database the results of our own research. As only a few studies have dealt with agricultural contamination, we also studied a soil toposequence from Brittany, France, that experienced spreading of pig slurry for tens of years. In the surface horizons of the natural soils, the δ{sup 65}Cu values vary from − 0.15 to 0.44‰ and the δ{sup 66}Zn from − 0.03 to 0.43‰. Furthermore, vertical variations along soil profiles range from − 0.95 to 0.44‰ for δ{sup 65}Cu and from − 0.53 to 0.64‰ for δ{sup 66}Zn values. We concluded that pedogenetic processes can produce isotopic fractionation, yet, it is not always discernible and can be overprinted by an exogenous isotopic signature. Furthermore, some contaminants are enriched in heavy Cu or in light Zn compared to the rock or soil, but no generalization can be made. The anthropogenic inputs can be identified based on stable Cu and Zn isotope ratios if the isotope ratios of the sources are different from those of the soil, which needs to be tested for each individual case. - Highlights: • Pedogenetic processes produce some Cu and Zn isotope fractionation. • Pollution with distinct isotopic signatures can be traced using Cu and Zn isotopes. • Tracing

  2. Tracing contamination sources in soils with Cu and Zn isotopic ratios

    International Nuclear Information System (INIS)

    Fekiacova, Z.; Cornu, S.; Pichat, S.

    2015-01-01

    Copper (Cu) and zinc (Zn) are naturally present and ubiquitous in soils and are important micronutrients. Human activities contribute to the input of these metals to soils in different chemical forms, which can sometimes reach a toxic level for soil organisms and plants. Isotopic signatures could be used to trace sources of anthropogenic Cu and Zn pollution. The aim of this paper is to determine whether it is possible to identify (i) Cu and Zn contamination in soils and their sources, on the basis of their isotopic signatures, and (ii) situations that are a priori favorable or not for tracing Cu and Zn pollution using the isotopic approach. Therefore, we compiled data from the literature on Cu and Zn isotopes in soils, rocks and pollutants and added to this database the results of our own research. As only a few studies have dealt with agricultural contamination, we also studied a soil toposequence from Brittany, France, that experienced spreading of pig slurry for tens of years. In the surface horizons of the natural soils, the δ 65 Cu values vary from − 0.15 to 0.44‰ and the δ 66 Zn from − 0.03 to 0.43‰. Furthermore, vertical variations along soil profiles range from − 0.95 to 0.44‰ for δ 65 Cu and from − 0.53 to 0.64‰ for δ 66 Zn values. We concluded that pedogenetic processes can produce isotopic fractionation, yet, it is not always discernible and can be overprinted by an exogenous isotopic signature. Furthermore, some contaminants are enriched in heavy Cu or in light Zn compared to the rock or soil, but no generalization can be made. The anthropogenic inputs can be identified based on stable Cu and Zn isotope ratios if the isotope ratios of the sources are different from those of the soil, which needs to be tested for each individual case. - Highlights: • Pedogenetic processes produce some Cu and Zn isotope fractionation. • Pollution with distinct isotopic signatures can be traced using Cu and Zn isotopes. • Tracing of the metal

  3. A Graphite Isotope Ratio Method: A Primer on Estimating Plutonium Production in Graphite Moderated Reactors

    International Nuclear Information System (INIS)

    Gesh, Christopher J.

    2004-01-01

    The Graphite Isotope Ratio Method (GIRM) is a technique used to estimate the total plutonium production in a graphite-moderated reactor. The cumulative plutonium production in that reactor can be accurately determined by measuring neutron irradiation induced isotopic ratio changes in certain impurity elements within the graphite moderator. The method does not require detailed knowledge of a reactor's operating history, although that knowledge can decrease the uncertainty of the production estimate. The basic premise of the Graphite Isotope Ratio Method is that the fluence in non-fuel core components is directly related to the cumulative plutonium production in the nuclear fuel

  4. Results from an interlaboratory exercise on the determination of plutonium isotopic ratios by gamma spectrometry

    International Nuclear Information System (INIS)

    Ottmar, H.

    1981-07-01

    Results form interlaboratory comparison measurements on the determination of plutonium isotopic ratios by gamma spectrometry, organized by the ESARDA Working Group on Techniques and Standards for Nondestructive Analysis, are presented and discussed. Nine laboratories from nine countries or international organizations participated in the intercomparison exercise, which included both laboratories' own measurements on the plutonium isotopic reference materials NBS-SRM 946, 947, 948 and comparison analyses of gamma spectra from these materials distributed to the participating laboratories. Results from the intercomparison analyses have been used to reevaluate some gamma branching intensity ratios required for plutonium isotopic ratio measurements. (orig.) [de

  5. Chlorine Isotope Effects from Isotope Ratio Mass Spectrometry Suggest Intramolecular C-Cl Bond Competition in Trichloroethene (TCE Reductive Dehalogenation

    Directory of Open Access Journals (Sweden)

    Stefan Cretnik

    2014-05-01

    Full Text Available Chlorinated ethenes are prevalent groundwater contaminants. To better constrain (biochemical reaction mechanisms of reductive dechlorination, the position-specificity of reductive trichloroethene (TCE dehalogenation was investigated. Selective biotransformation reactions (i of tetrachloroethene (PCE to TCE in cultures of Desulfitobacterium sp. strain Viet1; and (ii of TCE to cis-1,2-dichloroethene (cis-DCE in cultures of Geobacter lovleyi strain SZ were investigated. Compound-average carbon isotope effects were −19.0‰ ± 0.9‰ (PCE and −12.2‰ ± 1.0‰ (TCE (95% confidence intervals. Using instrumental advances in chlorine isotope analysis by continuous flow isotope ratio mass spectrometry, compound-average chorine isotope effects were measured for PCE (−5.0‰ ± 0.1‰ and TCE (−3.6‰ ± 0.2‰. In addition, position-specific kinetic chlorine isotope effects were determined from fits of reactant and product isotope ratios. In PCE biodegradation, primary chlorine isotope effects were substantially larger (by −16.3‰ ± 1.4‰ (standard error than secondary. In TCE biodegradation, in contrast, the product cis-DCE reflected an average isotope effect of −2.4‰ ± 0.3‰ and the product chloride an isotope effect of −6.5‰ ± 2.5‰, in the original positions of TCE from which the products were formed (95% confidence intervals. A greater difference would be expected for a position-specific reaction (chloride would exclusively reflect a primary isotope effect. These results therefore suggest that both vicinal chlorine substituents of TCE were reactive (intramolecular competition. This finding puts new constraints on mechanistic scenarios and favours either nucleophilic addition by Co(I or single electron transfer as reductive dehalogenation mechanisms.

  6. Insights into Wilson's Warbler migration from analyses of hydrogen stable-isotope ratios

    Science.gov (United States)

    Jeffrey F. Kelly; Viorel Atudorei; Zachary D. Sharp; Deborah M. Finch

    2002-01-01

    Our ability to link the breeding locations of individual passerines to migration stopover sites and wintering locations is limited. Stable isotopes of hydrogen contained in bird feathers have recently shown potential in this regard. We measured hydrogen stable-isotope ratios (deltaD) of feathers from breeding, migrating, and wintering Wilson's Warblers. Analyses...

  7. Assessment of primary production in a eutrophic lake from carbon and nitrogen isotope ratios of a carnivorous fish

    International Nuclear Information System (INIS)

    Yoshioka, Takahito

    1991-01-01

    The carbon and nitrogen isotope ratios of Hypomesus transpacificus (a pond smelt) in a eutrophic lake, Lake Suwa, were measured from April to September in 1986 and 1987. The differences in the isotope ratios between these two years were observed. The stable isotopes were transferred from phytoplankton to zooplankton and pond smelt, associated with organic matters. Therefore, the difference in the isotope ratios in two years seemed to reflect the differences of the proceeding of primary production. It was suggested that the carbon and nitrogen isotope ratios of animal, whose trophic level is far from primary producer, can be the qualitative indicators for assessing the primary production in a lake ecosystem. (author)

  8. Sulfur isotope in nature. Determination of sulfur isotope ratios in coal and petroleum by mass spectrometry

    International Nuclear Information System (INIS)

    Derda, M.

    1999-01-01

    Elementary sulfur or in chemical compounds is one of the elements widespread in the earth's crust and biosphere. Its participation in earth's crust amounts to 0.26 % by weight. Measurement of isotope composition of natural samples can deliver many information about origin, creation and transformation ranges of rocks and minerals. Sulfur isotope ratio contained in minerals is variable and for this reason investigation of isotope sulfur composition can deliver useful information about the geochemistry of each component. Therefore in the investigated sample it is necessary to determine not only the content of sulfur but also the isotope composition of each component. Differentiation of contents of sulfur-34 in natural sulfur compounds can reach up to 110 per mile. So large divergences can be explained by a kinetic effect or by bacterial reduction of sulphates. In this report a wide review of the results of investigations of isotope sulfur compositions in coal and petroleum are presented as well as the methods for the preparation of samples for mass spectrometry analysis are proposed. (author)

  9. Intrinsic ratios of glucose, fructose, glycerol and ethanol 13C/12C isotopic ratio determined by HPLC-co-IRMS: toward determining constants for wine authentication.

    Science.gov (United States)

    Guyon, François; Gaillard, Laetitia; Salagoïty, Marie-Hélène; Médina, Bernard

    2011-09-01

    High-performance liquid chromatography linked to isotope ratio mass spectrometry (HPLC-co-IRMS) via a Liquiface© interface has been used to simultaneously determine (13)C isotope ratios of glucose (G), fructose (F), glycerol (Gly) and ethanol (Eth) in sweet and semi-sweet wines. The data has been used the study of wine authenticity. For this purpose, 20 authentic wines from various French production areas and various vintages have been analyzed after dilution in pure water from 20 to 200 times according to sugar content. If the (13)C isotope ratios vary according to the production area and the vintage, it appears that internal ratios of (13)C isotope ratios (R((13)C)) of the four compounds studied can be considered as a constant. Thus, ratios of isotope ratios are found to be 1.00 ± 0.04 and 1.02 ± 0.08 for R((13)C(G/F)) and R((13)C(Gly/Eth)), respectively. Moreover, R((13)C(Eth/Sugar)) is found to be 1.15 ± 0.10 and 1.16 ± 0.08 for R((13)C(Gly/Sugar)). Additions of glucose, fructose and glycerol to a reference wine show a variation of the R((13)C) value for a single product addition as low as 2.5 g/L(-1). Eighteen commercial wines and 17 concentrated musts have been analyzed. Three wine samples are suspicious as the R((13)C) values are out of range indicating a sweetening treatment. Moreover, concentrated must analysis shows that (13)C isotope ratio can be also used directly to determine the authenticity of the matrix.

  10. Isotopic identification of natural vs. anthropogenic lead sources in marine sediments from the inner Ria de Vigo (NW Spain)

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez-Iglesias, P., E-mail: palvarez@uvigo.es [Department of Marine Geosciences and Land Use Management, Faculty of Marine Sciences, University of Vigo (Spain); Laboratorio de Analisis Quimico Instrumental, C.A.C.T.I., Universidad de Vigo (Spain); Rubio, B., E-mail: brubio@uvigo.es [Department of Marine Geosciences and Land Use Management, Faculty of Marine Sciences, University of Vigo (Spain); Millos, J., E-mail: jmillos@uvigo.es [Laboratorio de Analisis Quimico Instrumental, C.A.C.T.I., Universidad de Vigo (Spain)

    2012-10-15

    San Simon Bay, the inner part of the Ria de Vigo (NW Spain), an area previously identified as highly polluted by Pb, was selected for the application of Pb stable isotope ratios as a fingerprinting tool in subtidal and intertidal sediment cores. Lead isotopic ratios were determined by inductively coupled plasma mass spectrometry on extracts from bulk samples after total acid digestion. Depth-wise profiles of {sup 206}Pb/{sup 207}Pb, {sup 206}Pb/{sup 204}Pb, {sup 207}Pb/{sup 204}Pb, {sup 208}Pb/{sup 204}Pb and {sup 208}Pb/{sup 207}Pb ratios showed, in general, an upward decrease for both intertidal and subtidal sediments as a consequence of the anthropogenic activities over the last century, or centuries. Waste channel samples from a nearby ceramic factory showed characteristic Pb stable isotope ratios different from those typical of coal and petrol. Natural isotope ratios from non-polluted samples were established for the study area, differentiating sediments from granitic or schist-gneiss sources. A binary mixing model employed on the polluted samples allowed estimating the anthropogenic inputs to the bay. These inputs represented between 25 and 98% of Pb inputs in intertidal samples, and 9-84% in subtidal samples, their contributions varying with time. Anthropogenic sources were apportioned according to a three-source model. Coal combustion-related emissions were the main anthropogenic source Pb to the bay (60-70%) before the establishment of the ceramic factory in the area (in the 1970s) which has since constituted the main source (95-100%), followed by petrol-related emissions. The Pb inputs history for the intertidal area was determined for the 20th century, and, for the subtidal area, the 19th and 20th centuries. -- Highlights: Black-Right-Pointing-Pointer Pb stable isotope ratios were applied to study Pb sources in coastal sediments. Black-Right-Pointing-Pointer Pb isotopic ratios were determined for pre-pollution and for industrial samples. Black

  11. Lead isotope approach to the understanding of early Japanese bronze culture

    International Nuclear Information System (INIS)

    Mabuchi, H.; Hirao, Y.

    1985-01-01

    For several years, the authors have used lead isotope analysis to investigate extensively the provenance of ancient bronze or copper artifacts which had been excavated mainly from Japanese archaeological sites. The results have been published item by item in several relevant Japanese journals. This review is intended to give an account which will review the whole work relating early Japanese bronze culture to Chinese and Korean cultures through lead isotope study. (author)

  12. The calculation of isotopic partition function ratios by a perturbation theory technique

    International Nuclear Information System (INIS)

    Singh, G.; Wolfsberg, M.

    1975-01-01

    The vibrational Hamiltonian of a molecule in the harmonic approximation, H = (1/2) Σ (g/subi/jp/subi/p/subj/ + f/subi/jq/subi/q/subj/), has been divided into a diagonal part (terms with i=j) and an off-diagonal part (inot-equalj), which is regarded as the perturbation. The vibrational partition function of the molecule is then calculated by Schwinger perturbation theory as the partition function of the unperturbed problem, corresponding to a collection of oscillators with frequencies 2πν/subi/' = (f/subi/ig/subi/i)/sup 1 / 2 /, plus perturbation correction terms which are calculated to second order. With the usual assumptions of isotope effect calculations that the molecular translations and rotations are classical and separable from the vibrations, the perturbation formulation of the vibrational partition function is easily transformed into a perturbation theory formulation of (reduced) isotopic partition function ratios. If, for example, the molecular potential function is expressed in terms of the displacements of bond stretches and bond angle bends from their respective equilibrium values, the unperturbed partition function ratio corresponds to the isotope effect expected for noninteracting bond-stretch and bond-angle-bend oscillators. Detailed comparison is made for a number of molecular systems of perturbation theory calculations of partition functions and isotopic partition function ratios with exact calculations carried out by actually obtaining the normal mode vibrational frequencies of the vibrational Hamiltonian. Good agreement is found. The utility of the perturbation theory formulation resides in the fact that it permits one to look at isotope effects in a very simple manner; some demonstrations are given

  13. Sequential extraction combined with isotope analysis as a tool for the investigation of lead mobilisation in soils: Application to organic-rich soils in an upland catchment in Scotland

    International Nuclear Information System (INIS)

    Bacon, Jeffrey R.; Farmer, John G.; Dunn, Sarah M.; Graham, Margaret C.; Vinogradoff, Susan I.

    2006-01-01

    Sequential extraction (modified BCR procedure) combined with isotope analysis has been investigated as a tool for assessing mobilisation of lead into streams at an upland catchment in NE Scotland. The maximum lead concentrations (up to 110 mg kg -1 in air-dried soil) occurred not at the surface but at about 10 cm depth. The lowest 206 Pb/ 207 Pb ratios in any profile occurred, with one exception, at 2.5-5 cm depth. In the one exception, closest to the only road in the area, significantly lower 206 Pb/ 207 Pb ratios in the surface soil together with much increased chloride concentrations (in comparison to other surface waters) indicated the possible mobilisation of roadside lead and transfer to the stream. The 206 Pb/ 207 Pb ratios in extractable fractions tended at depth towards the ratio measured in the residual phase but the ratios in the oxidizable fraction increased to a value higher than that of the residual phase. - Sequential extraction combined with isotope analysis was used as a tool to assess mobilisation of lead into streams

  14. Novel Apparatus for the Real-Time Quantification of Dissolved Gas Concentrations and Isotope Ratios

    Science.gov (United States)

    Gupta, M.; Leen, J.; Baer, D. S.; Owano, T. G.; Liem, J.

    2013-12-01

    Measurements of dissolved gases and their isotopic composition are critical in studying a variety of phenomena, including underwater greenhouse gas generation, air-surface exchange, and pollution migration. These studies typically involve obtaining water samples from streams, lakes, or ocean water and transporting them to a laboratory, where they are degased. The gases obtained are then generally measured using gas chromatography and isotope ratio mass spectrometry for concentrations and isotope ratios, respectively. This conventional, off-line methodology is time consuming, significantly limits the number of the samples that can be measured and thus severely inhibits detailed spatial and temporal mapping of gas concentrations and isotope ratios. In this work, we describe the development of a new membrane-based degassing device that interfaces directly to Los Gatos Research (cavity enhanced laser absorption or Off-Axis ICOS) gas analyzers (cavity enhanced laser absorption or Off-Axis ICOS analyzers) to create an autonomous system that can continuously and quickly measure concentrations and isotope ratios of dissolved gases in real time in the field. By accurately controlling the water flow rate through the membrane degasser, gas pressure on the outside of the membrane, and water pressure on the inside of the membrane, the system is able to generate precise and highly reproducible results. Moreover, by accurately measuring the gas flow rates in and out of the degasser, the gas-phase concentrations (ppm) could be converted into dissolved gas concentrations (nM). We will present detailed laboratory test data that quantifies the linearity, precision, and dynamic range of the system for the concentrations and isotope ratios of dissolved methane, carbon dioxide, and nitrous oxide. By interfacing the degassing device to a novel cavity-enhanced spectrometer (developed by LGR), preliminary data will also be presented for dissolved volatile organics (VOC) and other

  15. Hydrogen and oxygen stable isotope ratios of milk in the United States.

    Science.gov (United States)

    Chesson, Lesley A; Valenzuela, Luciano O; O'Grady, Shannon P; Cerling, Thure E; Ehleringer, James R

    2010-02-24

    Models of hydrogen and oxygen incorporation in human tissues recognize the impact of geographic location on the isotopic composition of fluid intake, but inputs can include nonlocal beverages, such as milk. Milk and cow drinking water were collected from dairies, and commercially available milk was purchased from supermarkets and fast food restaurants. It was hypothesized that milk water delta(2)H and delta(18)O values record geographic location information. Correlations between milk water isotope ratios and purchase location tap water were significant. However, the amount of variation in milk delta(2)H and delta(18)O values explained by tap water was low, suggesting a single estimation of fluid input isotope ratios may not always be adequate in studies. The delta(2)H and delta(18)O values of paired milk and cow drinking water were related, suggesting potential for geographical origin assignment using stable isotope analysis. As an application example, milk water delta(18)O values were used to predict possible regions of origin for restaurant samples.

  16. Concerns about Quadrupole ICP-MS Lead Isotopic Data and Interpretations in the Environment and Health Fields

    Directory of Open Access Journals (Sweden)

    Brian Gulson

    2018-04-01

    Full Text Available There has been a massive increase in recent years of the use of lead (Pb isotopes in attempts to better understand sources and pathways of Pb in the environment and in man or experimental animals. Unfortunately, there have been many cases where the quality of the isotopic data, especially that obtained by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS, are questionable, resulting in questionable identification of potential sources, which, in turn, impacts study interpretation and conclusions. We present several cases where the isotopic data have compromised interpretation because of the use of only the major isotopes 208Pb/206Pb and 207Pb/206Pb, or their graphing in other combinations. We also present some examples comparing high precision data from thermal ionization (TIMS or multi-collector plasma mass spectrometry (MC-ICP-MS to illustrate the deficiency in the Q-ICP-MS data. In addition, we present cases where Pb isotopic ratios measured on Q-ICP-MS are virtually impossible for terrestrial samples. We also evaluate the Pb isotopic data for rat studies, which had concluded that Pb isotopic fractionation occurs between different organs and suggest that this notion of biological fractionation of Pb as an explanation for isotopic differences is not valid. Overall, the brief review of these case studies shows that Q-ICP-MS as commonly practiced is not a suitable technique for precise and accurate Pb isotopic analysis in the environment and health fields.

  17. Concerns about Quadrupole ICP-MS Lead Isotopic Data and Interpretations in the Environment and Health Fields.

    Science.gov (United States)

    Gulson, Brian; Kamenov, George D; Manton, William; Rabinowitz, Michael

    2018-04-11

    There has been a massive increase in recent years of the use of lead (Pb) isotopes in attempts to better understand sources and pathways of Pb in the environment and in man or experimental animals. Unfortunately, there have been many cases where the quality of the isotopic data, especially that obtained by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS), are questionable, resulting in questionable identification of potential sources, which, in turn, impacts study interpretation and conclusions. We present several cases where the isotopic data have compromised interpretation because of the use of only the major isotopes 208 Pb/ 206 Pb and 207 Pb/ 206 Pb, or their graphing in other combinations. We also present some examples comparing high precision data from thermal ionization (TIMS) or multi-collector plasma mass spectrometry (MC-ICP-MS) to illustrate the deficiency in the Q-ICP-MS data. In addition, we present cases where Pb isotopic ratios measured on Q-ICP-MS are virtually impossible for terrestrial samples. We also evaluate the Pb isotopic data for rat studies, which had concluded that Pb isotopic fractionation occurs between different organs and suggest that this notion of biological fractionation of Pb as an explanation for isotopic differences is not valid. Overall, the brief review of these case studies shows that Q-ICP-MS as commonly practiced is not a suitable technique for precise and accurate Pb isotopic analysis in the environment and health fields.

  18. Age, genesis and exploration for mineral deposits: the possibilities offered by lead isotopes

    International Nuclear Information System (INIS)

    Marcoux, E.; Calvez, J.Y.

    1985-01-01

    After a brief theoretical survey of the subject, the paper discusses the assistance that lead isotopes can bring to solving problems of metallogenesis and mineral exploration. Lead isotopes act as a true geologic clock when radioactive decay of lead takes place in a closed U-Th-Pb system, or when these conditions have been recreated by homogenization of a large crustal segment. The lead clock is thus reliable for deposits whose process of formation was part of a hydrothermal event that affected a significant part of the crust, most importantly in island-arc volcanosedimentary deposits, much less so for deposits formed by spatially restricted hydrothermal activity such as the emplacement of veins. Very interesting possibilities are also to be found in the capacity of lead isotopes to act as geochemical tracers. In conjunction with paragenetic and gitologic studies, determination of the isotopic composition of lead allows the sources of metals to be identified and permits an approach to the understanding of inheritance phenomena in a mineral deposit or province. This information also assists in unravelling the successive metallogenic processes in a region, thus contributing to refinement of the concept of a metallogenic province. Lastly lead isotopes provide an additional factor in assessing the economic potential of a deposit undergoing exploration. The method is based on a comparison of the isotopic signature of the deposit with that of economic mineralization occuring elsewhere in the circa. Examples of stratiform deposits and the gold-bearing veins of Limousin are described. The application of this method to gossans can provide additional information to standard geochemistry and thus assist in grading of targets [fr

  19. Cross contamination in dual inlet isotope ratio mass spectrometers

    NARCIS (Netherlands)

    Meijer, H.A.J.; Neubert, R.E.M.; Visser, G.H.

    2000-01-01

    Since the early days of geochemical isotope ratio mass spectrometry there has always been the problem of cross contamination, i.e. the contamination of the sample gas with traces of reference gas land vice versa) in a dual inlet system and the analyzer itself. This was attributable to valve leakages

  20. Pb isotopic composition of the atmosphere of the Sao Paulo city, Brazil, and isotopic characterization of some pollutant sources

    International Nuclear Information System (INIS)

    Aily, C.; Babinski, M.; Ruiz, I.R.; Sato, K

    2001-01-01

    Lead isotopes are known to be good tools for surveying lead origin in atmospheric samples (Chow et al., 1975). Lead has four naturally occurring stable isotopes: 206 Pb, 207 Pb, 208 Pb and 204 Pb. The first three isotopes are end products of radioactive decay chains from 238 U, 235 U and 232 Th, respectively, and the last one is non-radiogenic. Therefore, their abundance and the ratios among the four isotopes gradually change with time. Lead in the atmosphere comes from various sources, such as leaded gasoline, industrial emissions and coal combustion. Thus, lead isotope ratios different from those of the mother rock in the region are often observed in the atmosphere (Tatsumoto and Patterson, 1963). Lead is emitted to the atmosphere in fine particles, which can be transported within air masses for very long distances, e. g. from mid latitude regions to the Artic and Antarctica (Sturges and Barrie, 1989). Lead isotopes have been used to trace the pollutant sources in many cities of the world. However, a systematic study using this methodology has not been done in any Brazilian city. The main purpose of the present work is to characterize the Pb isotope composition in the atmosphere in Sao Paulo city, and suggest the possible pollutant sources. For our study lead isotopes were measured in different samples: aerosols and rainwater which would yield the Pb isotope composition of the atmosphere. Samples of gasoline and ethanol, gutter sweepings, soot from vehicle exhaust pipes, and filters containing particulate material from industrial emissions were also analyzed, since they were considered potential pollutant sources of the atmosphere. In order to obtain the local geogenic Pb isotopic composition we also analyzed rock and K-feldspar samples. Lead concentrations were only determined on aerosols and rainwater samples (au)

  1. Variations in the stable isotope ratios of specific aromatic and aliphatic hydrocarbons from coal conversion processes

    Energy Technology Data Exchange (ETDEWEB)

    McRae, C.; Snape, C.E.; Fallick, A.E. [University of Strathclyde, Glasgow (United Kingdom). Dept. of Pure and Applied Chemistry

    1998-07-01

    To establish the scope for applying gas chromatography-isotope ratio mass spectrometry ({sup {delta}-13}C GC-IRMS) to molecular recognition problems in coal utilisation, {sup 13}C/{sup 12}C isotope ratios were determined for n-alkanes and polycyclic aromatic hydrocarbons (PAHs) as a function of coal rank and process conditions. Six coals ranging from a lignite to a low volatile bituminous coal were subjected to chloroform extraction, fixed-bed pyrolysis under hydrogen pressure (hydropyrolysis) and fluidised-bed (flash) pyrolysis. No significant variations in the stable isotope ratios of n-alkanes were evident as a function of either rank or conversion regime. In contrast, the isotope ratios of PAHs show large variations with those for hydropyrolysis (-23 to -25 parts per thousand) being similar to the bulk values of the initial coals and being isotopically heavier (less negative) than their fluidised-bed pyrolysis counterparts by 2-3 parts per thousand. However, the PAHs from fluidised-bed pyrolysis, which resemble closely those obtained from high temperature coal carbonization, are still heavier (by 2-3 parts per thousand) than those from diesel particulates and coal gasification and combustion residues. This provides a firm basis for the source apportionment of airborne PAHs in the proximity of coking plants, particularly with no major variations in the PAH isotope ratios being found as a function of rank.

  2. Natural and anthropogenic lead in soils and vegetables around Guiyang city, southwest China: A Pb isotopic approach

    International Nuclear Information System (INIS)

    Li, Fei-Li; Liu, Cong-Qiang; Yang, Yuan-Gen; Bi, Xiang-Yang; Liu, Tao-Ze; Zhao, Zhi-Qi

    2012-01-01

    Soils, vegetables and rainwaters from three vegetable production bases in the Guiyang area, southwest China, were analyzed for Pb concentrations and isotope compositions to trace its sources in the vegetables and soils. Lead isotopic compositions were not distinguishable between yellow soils and calcareous soils, but distinguishable among sampling sites. The highest 207 Pb/ 206 Pb and 208 Pb/ 206 Pb ratios were found for rainwaters (0.8547–0.8593 and 2.098–2.109, respectively), and the lowest for soils (0.7173–0.8246 and 1.766–2.048, respectively). The 207 Pb/ 206 Pb and 208 Pb/ 206 Pb ratios increased in vegetables in the order of roots 207 Pb/ 206 Pb ratios versus the 208 Pb/ 206 Pb ratios from all samples formed a straight line and supported a binary end-member mixing model for Pb in vegetables. Using deep soils and rainwaters as geogenic and anthropogenic end members in the mixing model, it was estimated that atmospheric Pb contributed 30–77% to total Pb for vegetable roots, 43–71% for stems, 72–85% for leaves, and 90% for capsicum fruits, whereas 10–70% of Pb in all vegetable parts was derived from soils. This research supports that heavy metal contamination in vegetables can result mainly from atmospheric deposition, and Pb isotope technique is useful for tracing the sources of Pb contamination in vegetables.

  3. Natural and anthropogenic lead in soils and vegetables around Guiyang city, southwest China: A Pb isotopic approach

    Energy Technology Data Exchange (ETDEWEB)

    Li, Fei-Li [College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032 (China); Liu, Cong-Qiang, E-mail: liucongqiang@vip.skleg.cn [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China); Yang, Yuan-Gen [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China); Bi, Xiang-Yang [State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074 (China); Liu, Tao-Ze; Zhao, Zhi-Qi [State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002 (China)

    2012-08-01

    Soils, vegetables and rainwaters from three vegetable production bases in the Guiyang area, southwest China, were analyzed for Pb concentrations and isotope compositions to trace its sources in the vegetables and soils. Lead isotopic compositions were not distinguishable between yellow soils and calcareous soils, but distinguishable among sampling sites. The highest {sup 207}Pb/{sup 206}Pb and {sup 208}Pb/{sup 206}Pb ratios were found for rainwaters (0.8547-0.8593 and 2.098-2.109, respectively), and the lowest for soils (0.7173-0.8246 and 1.766-2.048, respectively). The {sup 207}Pb/{sup 206}Pb and {sup 208}Pb/{sup 206}Pb ratios increased in vegetables in the order of roots < stems < leaves < fruits. Plots of the {sup 207}Pb/{sup 206}Pb ratios versus the {sup 208}Pb/{sup 206}Pb ratios from all samples formed a straight line and supported a binary end-member mixing model for Pb in vegetables. Using deep soils and rainwaters as geogenic and anthropogenic end members in the mixing model, it was estimated that atmospheric Pb contributed 30-77% to total Pb for vegetable roots, 43-71% for stems, 72-85% for leaves, and 90% for capsicum fruits, whereas 10-70% of Pb in all vegetable parts was derived from soils. This research supports that heavy metal contamination in vegetables can result mainly from atmospheric deposition, and Pb isotope technique is useful for tracing the sources of Pb contamination in vegetables.

  4. Tracing contamination sources in soils with Cu and Zn isotopic ratios.

    Science.gov (United States)

    Fekiacova, Z; Cornu, S; Pichat, S

    2015-06-01

    Copper (Cu) and zinc (Zn) are naturally present and ubiquitous in soils and are important micronutrients. Human activities contribute to the input of these metals to soils in different chemical forms, which can sometimes reach a toxic level for soil organisms and plants. Isotopic signatures could be used to trace sources of anthropogenic Cu and Zn pollution. The aim of this paper is to determine whether it is possible to identify (i) Cu and Zn contamination in soils and their sources, on the basis of their isotopic signatures, and (ii) situations that are a priori favorable or not for tracing Cu and Zn pollution using the isotopic approach. Therefore, we compiled data from the literature on Cu and Zn isotopes in soils, rocks and pollutants and added to this database the results of our own research. As only a few studies have dealt with agricultural contamination, we also studied a soil toposequence from Brittany, France, that experienced spreading of pig slurry for tens of years. In the surface horizons of the natural soils, the δ(65)Cu values vary from -0.15 to 0.44‰ and the δ(66)Zn from -0.03 to 0.43‰. Furthermore, vertical variations along soil profiles range from -0.95 to 0.44‰ for δ(65)Cu and from -0.53 to 0.64‰ for δ(66)Zn values. We concluded that pedogenetic processes can produce isotopic fractionation, yet, it is not always discernible and can be overprinted by an exogenous isotopic signature. Furthermore, some contaminants are enriched in heavy Cu or in light Zn compared to the rock or soil, but no generalization can be made. The anthropogenic inputs can be identified based on stable Cu and Zn isotope ratios if the isotope ratios of the sources are different from those of the soil, which needs to be tested for each individual case. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Isotopic characterisation of lead in contaminated soils from the vicinity of a non-ferrous metal smelter near Plovdiv, Bulgaria

    Energy Technology Data Exchange (ETDEWEB)

    Bacon, Jeffrey R. [Macaulay Institute, Craigiebuckler, Aberdeen AB15 8QH (United Kingdom)]. E-mail: j.bacon@macaulay.ac.uk; Dinev, Nikolai S. [N Poushkarov Institute of Soil Science and Agroecology, Sofia (Bulgaria)

    2005-03-01

    Soil samples from the vicinity of a non-ferrous metal smelter near Plovdiv, Bulgaria contained very high concentrations of cadmium, lead and zinc (up to 140, 4900 and 5900 mg kg{sup -1}, respectively). A roadside soil in a relatively uncontaminated area also contained high concentrations of the same metals (24, 1550 and 1870 mg kg{sup -1}, respectively) indicating that the transport of ores could be a source of contamination. Even though the lead isotope ratios in all the samples fell within a very narrow range (for example, 1.186-1.195 for {sup 206}Pb/{sup 207}Pb), the samples could be differentiated into three distinct groups: ores ({sup 206}Pb/{sup 207}Pb and {sup 208}Pb/{sup 207}Pb ratios of 1.1874-1.1884 and 2.4755-2.4807, respectively), current deposition (1.1864 and 2.4704-2.4711, respectively) and local background (1.1927-1.1951 and 2.4772-2.4809, respectively). Although most of the current deposition has its origin in the ores used at the smelter, up to 12% could be from other sources such as petrol lead. - Although soils in the vicinity of a non-ferrous metal smelter near Plovdiv, Bulgaria, have become highly contaminated with the ores used, lead isotope analysis has revealed that up to 12% of current deposition could be from other sources such as petrol lead.

  6. Isotopic characterisation of lead in contaminated soils from the vicinity of a non-ferrous metal smelter near Plovdiv, Bulgaria

    International Nuclear Information System (INIS)

    Bacon, Jeffrey R.; Dinev, Nikolai S.

    2005-01-01

    Soil samples from the vicinity of a non-ferrous metal smelter near Plovdiv, Bulgaria contained very high concentrations of cadmium, lead and zinc (up to 140, 4900 and 5900 mg kg -1 , respectively). A roadside soil in a relatively uncontaminated area also contained high concentrations of the same metals (24, 1550 and 1870 mg kg -1 , respectively) indicating that the transport of ores could be a source of contamination. Even though the lead isotope ratios in all the samples fell within a very narrow range (for example, 1.186-1.195 for 206 Pb/ 207 Pb), the samples could be differentiated into three distinct groups: ores ( 206 Pb/ 207 Pb and 208 Pb/ 207 Pb ratios of 1.1874-1.1884 and 2.4755-2.4807, respectively), current deposition (1.1864 and 2.4704-2.4711, respectively) and local background (1.1927-1.1951 and 2.4772-2.4809, respectively). Although most of the current deposition has its origin in the ores used at the smelter, up to 12% could be from other sources such as petrol lead. - Although soils in the vicinity of a non-ferrous metal smelter near Plovdiv, Bulgaria, have become highly contaminated with the ores used, lead isotope analysis has revealed that up to 12% of current deposition could be from other sources such as petrol lead

  7. Determining tissue-lead levels in large game mammals harvested with lead bullets: human health concerns.

    Science.gov (United States)

    Tsuji, L J S; Wainman, B C; Jayasinghe, R K; VanSpronsen, E P; Liberda, E N

    2009-04-01

    Recently, the use of lead isotope ratios has definitively identified lead ammunition as a source of lead exposure for First Nations people, but the isotope ratios for lead pellets and bullets were indistinguishable. Thus, lead-contaminated meat from game harvested with lead bullets may also be contributing to the lead body burden; however, few studies have determined if lead bullet fragments are present in big game carcasses. We found elevated tissue-lead concentrations (up to 5,726.0 microg/g ww) in liver (5/9) and muscle (6/7) samples of big game harvested with lead bullets and radiographic evidence of lead fragments. Thus, we would advise that the tissue surrounding the wound channel be removed and discarded, as this tissue may be contaminated by lead bullet fragments.

  8. Toward a simple, repeatable, non-destructive approach to measuring stable-isotope ratios of water within tree stems

    Science.gov (United States)

    Raulerson, S.; Volkmann, T.; Pangle, L. A.

    2017-12-01

    Traditional methodologies for measuring ratios of stable isotopes within the xylem water of trees involve destructive coring of the stem. A recent approach involves permanently installed probes within the stem, and an on-site assembly of pumps, switching valves, gas lines, and climate-controlled structure for field deployment of a laser spectrometer. The former method limits the possible temporal resolution of sampling, and sample size, while the latter may not be feasible for many research groups. We present results from initial laboratory efforts towards developing a non-destructive, temporally-resolved technique for measuring stable isotope ratios within the xylem flow of trees. Researchers have used direct liquid-vapor equilibration as a method to measure isotope ratios of the water in soil pores. Typically, this is done by placing soil samples in a fixed container, and allowing the liquid water within the soil to come into isotopic equilibrium with the headspace of the container. Water can also be removed via cryogenic distillation or azeotropic distillation, with the resulting liquid tested for isotope ratios. Alternatively, the isotope ratios of the water vapor can be directly measured using a laser-based water vapor isotope analyzer. Well-established fractionation factors and the isotope ratios in the vapor phase are then used to calculate the isotope ratios in the liquid phase. We propose a setup which would install a single, removable chamber onto a tree, where vapor samples could non-destructively and repeatedly be taken. These vapor samples will be injected into a laser-based isotope analyzer by a recirculating gas conveyance system. A major part of what is presented here is in the procedure of taking vapor samples at 100% relative humidity, appropriately diluting them with completely dry N2 calibration gas, and injecting them into the gas conveyance system without inducing fractionation in the process. This methodology will be helpful in making

  9. Ore-lead isotopes and Grenville plate tectonics

    International Nuclear Information System (INIS)

    Farquhar, R.M.; Fletcher, I.R.

    1980-01-01

    Recent advances in the 'whole earth' modelling of evolutionary processes of Pb isotopes shed light upon the origin of the metals found in various types of ore deposits. On the bases of these models and several recently published data sets, we believe that the ore deposits formed in various plate tectonic environments may carry 'isotopic fingerprints' which, when used with other characteristics such as mineral assemblages, may identify the depositional environments of many ore bodies. In the present study Pb-isotopic measurements have been made of a number of Precambrain mineralization types and localities throughout the Central Metasedimentary Belt of the Grenville Province. The data for individual deposits are at best ambiguous, but fall into two groups sufficiently distinctive to allow some degree of 'fingerprint' identification. Comparisons with data from other areas suggest that the major periods of sedimentation within the Central Metasedimentary Belt accompanied plate rifting and/or island arc tectonic activity, with most of the mineralized lead being derived from mantle sources. Detailed comparisons between the Grenville and other regions are uncertain, mainly because there are few detailed high-accuracy data sets from younger, tectonically unambiguous mineral occurrences. We suggest that once these data sets are availble, isotopic fingerprinting may become diagnostic for deposits ranging well back into the Precambrain

  10. Raman spectroscopic studies of isotopic diatomic molecules and a technique for measuring stable isotope ratios using Raman scattering

    International Nuclear Information System (INIS)

    Harney, R.C.

    1976-01-01

    A method for measuring stable isotope ratios using Raman scattering has been developed. This method consists of simultaneously counting photons scattered out of a high-intensity laser beam by different isotopically-substituted molecules. A number of studies of isotopic diatomic molecules have been made. The Q-branches of the Raman spectra of the isotopic molecules 14 N 15 N and 16 O 18 O were observed at natural abundance in nitrogen and oxygen samples. Comparison of the ratios of the intensities of the Q-branches of the major nitrogen and oxygen isotopic molecules with mass spectrometric determinations of the isotopic compositions yielded scattering cross sections of 14 N 15 N relative to 14 N 14 N and 16 O 18 O relative to 16 O 16 O. These cross section ratios differ from unity, a difference which can be explained by considering nuclear mass effects on the Franck-Condon factors of the molecular transitions. The measured intensities of the 14 N 15 N and 16 O 18 O Q-branches provided the baseline data needed to make the previously-mentioned extrapolation. High-resolution (approximately 0.15 cm -1 ) spectra of the Q-branches of 14 N 14 N and 16 O 16 O yielded a direct determination of α/sub e/ (the difference between the rotational constant in the ground and first excited vibrational states) for these molecules. The measured values are in excellent agreement with those obtained by other means. Complete Raman spectra (pure rotation, rotation-vibration, and high-resolution Q-branch) were obtained on a sample of pure 18 O 18 O. Analysis of this data yielded the molecular parameters: the equilibrium internuclear separation r/sub e/, the moment of inertia I/sub e/, and the energy parameters α/sub e/, B/sub e/, and ΔG/sub 1 / 2 /. These are in good agreement with data obtained by microwave spectroscopy

  11. Study on strontium isotope abundance-ratio measurements by using a 13-MeV proton beam

    Science.gov (United States)

    Jeong, Cheol-Ki; Jang, Han; Lee, Goung-Jin

    2016-09-01

    The Rb-Sr dating method is used in dating Paleozoic and Precambrian rocks. This method measures the 87Rb and the 87Sr concentrations by using thermal ionization mass spectrometry (TIMS) [J. Hefne et al., Inter. J. Phys. Sci. 3(1), 28 (2008)]. In addition, it calculates the initial 87Sr/86Sr ratio to increase the reliability of Rb-Sr dating. In this study, the 87Sr/86Sr ratio was measured by using a 13-MeV proton accelerator. Proton kinetic energies are in the range of tens of megaelectronvolts, and protons have large absorption cross-sections for ( p, n) reactions with most substances. After absorbing a proton with such a high kinetic energy, an element is converted into a nuclide with its atomic number increased by one via nuclear transmutation. These nuclides usually have short half-lives and return to the original state through radioactive decay. When a strontium sample is irradiated with protons, nuclear transmutation occurs; thus, the strontium isotope present in the sample changes to a yttrium isotope, which is an activated radioisotope. Based on this, the 87Sr/86Sr ratio was calculated by analyzing the gamma-rays emitted by each yttrium isotope. The KIRAMS-13 cyclotron at the Cyclotron Center of Chosun University, where 13-MeV protons can be extracted, was utilized in our experiment. The 87Sr/86Sr isotope ratio was computed for samples irradiated with these protons, and the result was similar to the isotope ratio for the Standard Reference Material, i.e., 98.2 ± 3.4%. As part of the analysis, proton activation analyses were performed using 13-MeV protons, and the experimental results of this research suggest a possible approach for measuring the strontium-isotope abundance ratio of samples.

  12. Seeking excellence: An evaluation of 235 international laboratories conducting water isotope analyses by isotope-ratio and laser-absorption spectrometry.

    Science.gov (United States)

    Wassenaar, L I; Terzer-Wassmuth, S; Douence, C; Araguas-Araguas, L; Aggarwal, P K; Coplen, T B

    2018-03-15

    Water stable isotope ratios (δ 2 H and δ 18 O values) are widely used tracers in environmental studies; hence, accurate and precise assays are required for providing sound scientific information. We tested the analytical performance of 235 international laboratories conducting water isotope analyses using dual-inlet and continuous-flow isotope ratio mass spectrometers and laser spectrometers through a water isotope inter-comparison test. Eight test water samples were distributed by the IAEA to international stable isotope laboratories. These consisted of a core set of five samples spanning the common δ-range of natural waters, and three optional samples (highly depleted, enriched, and saline). The fifth core sample contained unrevealed trace methanol to assess analyst vigilance to the impact of organic contamination on water isotopic measurements made by all instrument technologies. For the core and optional samples ~73 % of laboratories gave acceptable results within 0.2 ‰ and 1.5 ‰ of the reference values for δ 18 O and δ 2 H, respectively; ~27 % produced unacceptable results. Top performance for δ 18 O values was dominated by dual-inlet IRMS laboratories; top performance for δ 2 H values was led by laser spectrometer laboratories. Continuous-flow instruments yielded comparatively intermediate results. Trace methanol contamination of water resulted in extreme outlier δ-values for laser instruments, but also affected reactor-based continuous-flow IRMS systems; however, dual-inlet IRMS δ-values were unaffected. Analysis of the laboratory results and their metadata suggested inaccurate or imprecise performance stemmed mainly from skill- and knowledge-based errors including: calculation mistakes, inappropriate or compromised laboratory calibration standards, poorly performing instrumentation, lack of vigilance to contamination, or inattention to unreasonable isotopic outcomes. To counteract common errors, we recommend that laboratories include 1-2 'known

  13. Seeking excellence: An evaluation of 235 international laboratories conducting water isotope analyses by isotope-ratio and laser-absorption spectrometry

    Science.gov (United States)

    Wassenaar, L. I.; Terzer-Wassmuth, S.; Douence, C.; Araguas-Araguas, L.; Aggarwal, P. K.; Coplen, Tyler B.

    2018-01-01

    RationaleWater stable isotope ratios (δ2H and δ18O values) are widely used tracers in environmental studies; hence, accurate and precise assays are required for providing sound scientific information. We tested the analytical performance of 235 international laboratories conducting water isotope analyses using dual-inlet and continuous-flow isotope ratio mass spectrometers and laser spectrometers through a water isotope inter-comparison test.MethodsEight test water samples were distributed by the IAEA to international stable isotope laboratories. These consisted of a core set of five samples spanning the common δ-range of natural waters, and three optional samples (highly depleted, enriched, and saline). The fifth core sample contained unrevealed trace methanol to assess analyst vigilance to the impact of organic contamination on water isotopic measurements made by all instrument technologies.ResultsFor the core and optional samples ~73 % of laboratories gave acceptable results within 0.2 ‰ and 1.5 ‰ of the reference values for δ18O and δ2H, respectively; ~27 % produced unacceptable results. Top performance for δ18O values was dominated by dual-inlet IRMS laboratories; top performance for δ2H values was led by laser spectrometer laboratories. Continuous-flow instruments yielded comparatively intermediate results. Trace methanol contamination of water resulted in extreme outlier δ-values for laser instruments, but also affected reactor-based continuous-flow IRMS systems; however, dual-inlet IRMS δ-values were unaffected.ConclusionsAnalysis of the laboratory results and their metadata suggested inaccurate or imprecise performance stemmed mainly from skill- and knowledge-based errors including: calculation mistakes, inappropriate or compromised laboratory calibration standards, poorly performing instrumentation, lack of vigilance to contamination, or inattention to unreasonable isotopic outcomes. To counteract common errors, we recommend that

  14. The Cascade Mountains revisited: A re-evaluation in light of new lead isotopic data

    International Nuclear Information System (INIS)

    Church, S.E.

    1976-01-01

    Lead isotopic analyses have been repeated using silica gel for several samples from the Cascade Mountains which were previously analyzed by lead sulfide. The improved precision indicates that some of the scatter in the original data was due to thermal fractionation; however, the bulk of the data have not changed significantly. Two-point mixing lines are demonstrated for main cone-satellitic cone pairs from Glacier Peak, Mt. Baker and Mt. Shasta. Comparison with data on oceanic basalts from the Juan de Fuca and Gorda Ridge area indicates that hypothesis of mixing of mid-ocean ridge (MOR) basalt lead and 'alkali basalt-like' lead from the oceanic crust is not tenable. Lead isotope analyses of pre-Astoria Fan sediments from DSDP Leg 18 sites and from the Eocene Tyee Formation indicate that the sedimentary continental detritus from the North American continent has the correct lead isotopic composition to be the continental component necessary to account for the Cascade Mountains lead isotopic array by mixing with Juan de Fuca-Gorda Ridge MOR basalts. However, from recent work on the structure of oceanic trenches by Karig and Sharman (1975), it does not appear that subduction of sediments is the rule. A model of crustal contamination and/or assimilation at the crust/mantle interface is the preferred explanation for the lead isotopic data from the Cascade Mountains. (Auth.)

  15. Measurement system analysis (MSA) of the isotopic ratio for uranium isotope enrichment process control

    Energy Technology Data Exchange (ETDEWEB)

    Medeiros, Josue C. de; Barbosa, Rodrigo A.; Carnaval, Joao Paulo R., E-mail: josue@inb.gov.br, E-mail: rodrigobarbosa@inb.gov.br, E-mail: joaocarnaval@inb.gov.br [Industrias Nucleares do Brasil (INB), Rezende, RJ (Brazil)

    2013-07-01

    Currently, one of the stages in nuclear fuel cycle development is the process of uranium isotope enrichment, which will provide the amount of low enriched uranium for the nuclear fuel production to supply 100% Angra 1 and 20% Angra 2 demands. Determination of isotopic ration n({sup 235}U)/n({sup 238}U) in uranium hexafluoride (UF{sub 6} - used as process gas) is essential in order to control of enrichment process of isotopic separation by gaseous centrifugation cascades. The uranium hexafluoride process is performed by gas continuous feeding in separation unit which uses the centrifuge force principle, establishing a density gradient in a gas containing components of different molecular weights. The elemental separation effect occurs in a single ultracentrifuge that results in a partial separation of the feed in two fractions: an enriched on (product) and another depleted (waste) in the desired isotope ({sup 235}UF{sub 6}). Industrias Nucleares do Brasil (INB) has used quadrupole mass spectrometry (QMS) by electron impact (EI) to perform isotopic ratio n({sup 235}U)/n({sup 238}U) analysis in the process. The decision of adjustments and change te input variables are based on the results presented in these analysis. A study of stability, bias and linearity determination has been performed in order to evaluate the applied method, variations and systematic errors in the measurement system. The software used to analyze the techniques above was the Minitab 15. (author)

  16. Pb isotopes of Gorgona Island (Colombia): Isotopic variations correlated with magma type

    International Nuclear Information System (INIS)

    Dupre, B.; Echeverria, L.M.

    1984-01-01

    Lead isotopic results obtained on komatiites and basalts from Gorgona Island provide evidence of large isotopic variations within a restricted area (8x2.5 km). The variations are correlated with differences in volcanic rock type. The highest isotopic ratios ( 206 Pb/ 204 Pbproportional19.75) correspond to tholeiites which make up most of the island. The lowest ratios (18.3) correspond to the komatiites of the west coast of the island. Other rock types (komatiites of the east coast, K-tholeiites, picrites and tuffs) have isotopic characteristics intermediate between these two extreme values. These results are explained by the existence of two distinct mantle sourbe regions, and by mixing or contamination between them. (orig.)

  17. Pb isotopes of Gorgona Island (Colombia): isotopic variations correlated with magma type

    Science.gov (United States)

    Dupré, B.; Echeverría, L. M.

    1984-02-01

    Lead isotopic results obtained on komatiites and basalts from Gorgona Island provide evidence of large isotopic variations within a restricted area (8 × 2.5 km). The variations are correlated with differences in volcanic rock type. The highest isotopic ratios ( 206Pb/ 204Pb˜ 19.75 ) correspond to tholeiites which make up most of the island. The lowest ratios (18.3) correspond to the komatiites of the west coast of the island. Other rock types (komatiites of the east coast, K-tholeiites, picrites and tuffs) have isotopic characteristics intermediate between these two extreme values. These results are explained by the existence of two distinct mantle source regions, and by mixing or contamination between them.

  18. Lead isotopes in archaean plutonic rocks

    International Nuclear Information System (INIS)

    Oversby, V.M.

    1978-01-01

    Archaean intrusive rocks have initial Pb isotopic compositions which show a varied and complex history for the source regions of the rocks. Even the oldest rocks from Greenland indicate heterogenous U and Pb distribution prior to 3800 m.y. ago. Source regions with μ values less than 7 must have played a significant role in the early history of the earth. By late Archaean time U/Pb ratios of source regions had increased substantially. Data from Australia and North America show distinct regional differences, both within and between continents. (Auth.)

  19. Correction of mass spectrometric isotope ratio measurements for isobaric isotopologues of O2, CO, CO2, N2O and SO2.

    Science.gov (United States)

    Kaiser, Jan; Röckmann, Thomas

    2008-12-01

    Gas isotope ratio mass spectrometers usually measure ion current ratios of molecules, not atoms. Often several isotopologues contribute to an ion current at a particular mass-to-charge ratio (m/z). Therefore, corrections have to be applied to derive the desired isotope ratios. These corrections are usually formulated in terms of isotope ratios (R), but this does not reflect the practice of measuring the ion current ratios of the sample relative to those of a reference material. Correspondingly, the relative ion current ratio differences (expressed as delta values) are first converted into isotopologue ratios, then into isotope ratios and finally back into elemental delta values. Here, we present a reformulation of this data reduction procedure entirely in terms of delta values and the 'absolute' isotope ratios of the reference material. This also shows that not the absolute isotope ratios of the reference material themselves, but only product and ratio combinations of them, are required for the data reduction. These combinations can be and, for carbon and oxygen have been, measured by conventional isotope ratio mass spectrometers. The frequently implied use of absolute isotope ratios measured by specially calibrated instruments is actually unnecessary. Following related work on CO2, we here derive data reduction equations for the species O2, CO, N2O and SO2. We also suggest experiments to measure the required absolute ratio combinations for N2O, SO2 and O2. As a prelude, we summarise historic and recent measurements of absolute isotope ratios in international isotope reference materials. Copyright 2008 John Wiley & Sons, Ltd.

  20. GasBench/isotope ratio mass spectrometry: a carbon isotope approach to detect exogenous CO(2) in sparkling drinks.

    Science.gov (United States)

    Cabañero, Ana I; San-Hipólito, Tamar; Rupérez, Mercedes

    2007-01-01

    A new procedure for the determination of carbon dioxide (CO(2)) (13)C/(12)C isotope ratios, using direct injection into a GasBench/isotope ratio mass spectrometry (GasBench/IRMS) system, has been developed to improve isotopic methods devoted to the study of the authenticity of sparkling drinks. Thirty-nine commercial sparkling drink samples from various origins were analyzed. Values of delta(13)C(cava) ranged from -20.30 per thousand to -23.63 per thousand, when C3 sugar addition was performed for a second alcoholic fermentation. Values of delta(13)C(water) ranged from -5.59 per thousand to -6.87 per thousand in the case of naturally carbonated water or water fortified with gas from the spring, and delta(13)C(water) ranged from -29.36 per thousand to -42.09 per thousand when industrial CO(2) was added. It has been demonstrated that the addition of C4 sugar to semi-sparkling wine (aguja) and industrial CO(2) addition to sparkling wine (cava) or water can be detected. The new procedure has advantages over existing methods in terms of analysis time and sample treatment. In addition, it is the first isotopic method developed that allows (13)C/(12)C determination directly from a liquid sample without previous CO(2) extraction. No significant isotopic fractionation was observed nor any influence by secondary compounds present in the liquid phase. Copyright (c) 2007 John Wiley & Sons, Ltd.

  1. Isotope ratio measurements with multiple collection inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Platzner, I.T.; Segal, I.; Halicz, L.

    2003-01-01

    In the studies summarized in this review, it has been shown that IRM of lead in silicates can be carried out without lead separation and purification. Because of time independent mass discrimination and lack of chemical interaction at high plasma temperatures, simple interference corrections are feasible. This data further support the observation that MC-ICP-MS provides data with superior precision comparing to TIMS. Furthermore, it should be noted that the multi collection instrumental configuration exhibits the capability to perform a single IRM with excellent precision and high accuracy for elements with a large number of isotopes. Four of the discussed elements have six (Er) and seven (Dy, Yb, Os) isotopes

  2. Determination of the isotopic ratio 235U/238U in UF6 using quadrupole mass spectrometry

    International Nuclear Information System (INIS)

    Kusahara, Helena Sueco

    1979-01-01

    In this work measurements of isotope ratios 235 U / 23 '8U in uranium hexafluoride are carried out using a quadrupole mass spectrometer. The operational parameters, which affect the final precision of the results, are standardized. Optimized procedures for the preparation of uranium hexafluoride samples by fluorination of uranium oxides using cobalt trifluoride method are established. Careful attention is given to the process of purification of uranium hexafluoride samples by fractional distillation. Adequate statistical methods for analysing the results obtained for single ratio measurements as well as the ratio ' of isotopic ratios of sample and standard ar.e developed. A precision of about 10 -4 for single ratio measurements and accuracy of about 0,3% for the ratio of sample and standard ratios are obtained. These results agree with the values which have been obtained using magnetic mass spectrometers. The procedures and methods established in this work can be employed in the systematic uranium isotope analysis in UF 6 form. (author)

  3. Isotopes and the early evolution of the earth

    International Nuclear Information System (INIS)

    Russell, R.D.

    1980-01-01

    The observed isotopic ratios of lead, strontium, neodymium, helium, and argon contain information about the chemical abundances of selected parent and daughter elements in the outer parts of the Earth. By necessity, we observe these isotopic ratios at the Earth's surface, which is a small, highly evolved part of the Earth. The studies of such isotopic ratios permit inferences to be made about interactions between this crust and the upper mantle. Helium has been especially valuable for demonstrating that primordial materials are still being outgassed from the earth. Models based on the observed argon isotopic ratios have lead to contradictory conclusions about the existence of an early period of extensive outgassing of the Earth. Lead has been a particularly interesting element because the ratio of the parents, 235 U/ 238 U, was very different in the Earth's early history than it is now. Therefore there is the potential for determining constraints on the early history of the Earth. A number of recently published papers offering lead isotope interpretations that reflect on the Earth's early history are reviewed, with special reference to models that are based upon uni-directional and bi-directional exchange between a protocrust and a residual mantle. Geochemical parameters for uranium, thorium and lead can be inferred for two evolving systems, as well as rate constants for differentiation. The principal conclusions are that the differentiation process extended beyond the first quarter of the Earth's history, and that it is possible to reproduce exactly the apparent oceanic basalt isochron by a simple two-reservoir model. In particular, such a model can explain quantitatively the observed lead-207 deficiency in the oceanic basalts

  4. A Three End-Member Mixing Model Based on Isotopic Composition and Elemental Ratio

    Directory of Open Access Journals (Sweden)

    Kon-Kee Liu Shuh-Ji Kao

    2007-01-01

    Full Text Available A three end-member mixing model based on nitrogen isotopic composition and organic carbon to nitrogen ratio of suspended particulate matter in an aquatic environment has been developed. Mathematical expressions have been derived for the calculation of the fractions of nitrogen or organic carbon originating from three different sources of distinct isotopic and elemental compositions. The model was successfully applied to determine the contributions from anthropogenic wastes, soils and bedrock-derived sediments to particulate nitrogen and particulate organic carbon in the Danshuei River during the flood caused by Typhoon Bilis in August 2000. The model solutions have been expressed in a general form that allows applications to mixtures with other types of isotopic compositions and elemental ratios or in forms other than suspended particulate matter.

  5. Improved detection of sugar addition to maple syrup using malic acid as internal standard and in 13C isotope ratio mass spectrometry (IRMS).

    Science.gov (United States)

    Tremblay, Patrice; Paquin, Réal

    2007-01-24

    Stable carbon isotope ratio mass spectrometry (delta13C IRMS) was used to detect maple syrup adulteration by exogenous sugar addition (beet and cane sugar). Malic acid present in maple syrup is proposed as an isotopic internal standard to improve actual adulteration detection levels. A lead precipitation method has been modified to isolate quantitatively malic acid from maple syrup using preparative reversed-phase liquid chromatography. The stable carbon isotopic ratio of malic acid isolated from this procedure shows an excellent accuracy and repeatability of 0.01 and 0.1 per thousand respectively, confirming that the modified lead precipitation method is an isotopic fractionation-free process. A new approach is proposed to detect adulteration based on the correlation existing between the delta13Cmalic acid and the delta13Csugars-delta13Cmalic acid (r = 0.704). This technique has been tested on a set of 56 authentic maple syrup samples. Additionally, authentic samples were spiked with exogeneous sugars. The mean theoretical detection level was statistically lowered using this technique in comparison with the usual two-standard deviation approach, especially when maple syrup is adulterated with beet sugar : 24 +/- 12% of adulteration detection versus 48 +/- 20% (t-test, p = 7.3 x 10-15). The method was also applied to published data for pineapple juices and honey with the same improvement.

  6. Reduction of determinate errors in mass bias-corrected isotope ratios measured using a multi-collector plasma mass spectrometer

    International Nuclear Information System (INIS)

    Doherty, W.

    2015-01-01

    A nebulizer-centric instrument response function model of the plasma mass spectrometer was combined with a signal drift model, and the result was used to identify the causes of the non-spectroscopic determinate errors remaining in mass bias-corrected Pb isotope ratios (Tl as internal standard) measured using a multi-collector plasma mass spectrometer. Model calculations, confirmed by measurement, show that the detectable time-dependent errors are a result of the combined effect of signal drift and differences in the coordinates of the Pb and Tl response function maxima (horizontal offset effect). If there are no horizontal offsets, then the mass bias-corrected isotope ratios are approximately constant in time. In the absence of signal drift, the response surface curvature and horizontal offset effects are responsible for proportional errors in the mass bias-corrected isotope ratios. The proportional errors will be different for different analyte isotope ratios and different at every instrument operating point. Consequently, mass bias coefficients calculated using different isotope ratios are not necessarily equal. The error analysis based on the combined model provides strong justification for recommending a three step correction procedure (mass bias correction, drift correction and a proportional error correction, in that order) for isotope ratio measurements using a multi-collector plasma mass spectrometer

  7. Hepatoblastoma Biology Using Isotope Ratio Mass Spectrometry: Utility of a Unique Technique for the Analysis of Oncological Specimens.

    Science.gov (United States)

    Taran, Katarzyna; Frączek, Tomasz; Sitkiewicz, Anna; Sikora-Szubert, Anita; Kobos, Józef; Paneth, Piotr

    2016-07-07

    Hepatoblastoma is the most common primary liver tumor in children. However, it occurs rarely, with an incidence of 0.5-1.5 cases per million children. There is no clear explanation of the relationship between clinicopathologic features, therapy, and outcome in hepatoblastoma cases, so far. One of the most widely accepted prognostic factors in hepatoblastoma is histology of the tumor. The aim of the study was to determine the potential differences in biology of hepatoblastoma histological subtypes at the atomic level using the unique method of isotope ratio mass spectrometry, which is especially valuable in examination of small groups of biological samples. Twenty-four measurements of nitrogen stable isotope ratio, carbon stable isotope ratio and total carbon to nitrogen mass ratio in fetal and embryonal hepatoblastoma tissue were performed using a Sercon 20-22 Continuous Flow Isotope Ratio Mass Spectrometer (CF-IRMS) coupled with a Sercon SL elemental analyzer for simultaneous carbon-nitrogen-sulfur (NCS) analysis. A difference of about 1.781‰ in stable nitrogen isotope 15N/14N ratio was found between examined hepatoblastoma histological subtypes. The prognosis in liver tumors cases in children may be challenging particularly because of the lack of versatile methods of its evaluation. Isotope ratio mass spectrometry allows one to determine the difference between hepatoblastoma histological subtypes and clearly indicates the cases with the best outcome.

  8. Use of lead isotopic composition in sulfides for the mineral-formation geochronology

    International Nuclear Information System (INIS)

    Ordynets, G.E.

    1977-01-01

    A study of the isotopic composition of lead in pyrites and galenites of a hydrothermal uranium deposit makes it possible to determine the time of ore formation. A few types of lead ores are distinguished. Each type corresponds to a definite period of mineralization and is characterized by a specific isotopic composition. The Cimmerian age of carbonate-sulphide veins has been established, the deposit being formed over a period of 150-200 million years

  9. Determination of carbon isotope ratios in plant starch via selective enzymatic hydrolysis

    International Nuclear Information System (INIS)

    Schimmelmann, A.; DeNiro, M.J.

    1983-01-01

    A method for the determination of the carbon isotope ratios in bipolymers hydrolyzed by enzymatic action consists of separating the monomer by passage through a dialysis membrane and then combusting the monomer prior to isotopic analysis. The method is described for application to the analysis of starch, but it should find application for polymers than can be degraded quantitatively to monomers and/or oligomers using specific hydrolytic enzymes

  10. Emission ratio and isotopic signatures of molecular hydrogen emissions from tropical biomass burning

    Science.gov (United States)

    Haumann, F. A.; Batenburg, A. M.; Pieterse, G.; Gerbig, C.; Krol, M. C.; Röckmann, T.

    2013-09-01

    In this study, we identify a biomass-burning signal in molecular hydrogen (H2) over the Amazonian tropical rainforest. To quantify this signal, we measure the mixing ratios of H2 and several other species as well as the H2 isotopic composition in air samples that were collected in the BARCA (Balanço Atmosférico Regional de Carbono na Amazônia) aircraft campaign during the dry season. We derive a relative H2 emission ratio with respect to carbon monoxide (CO) of 0.31 ± 0.04 ppb ppb-1 and an isotopic source signature of -280 ± 41‰ in the air masses influenced by tropical biomass burning. In order to retrieve a clear source signal that is not influenced by the soil uptake of H2, we exclude samples from the atmospheric boundary layer. This procedure is supported by data from a global chemistry transport model. The ΔH2 / ΔCO emission ratio is significantly lower than some earlier estimates for the tropical rainforest. In addition, our results confirm the lower values of the previously conflicting estimates of the H2 isotopic source signature from biomass burning. These values for the emission ratio and isotopic source signatures of H2 from tropical biomass burning can be used in future bottom-up and top-down approaches aiming to constrain the strength of the biomass-burning source for H2. Hitherto, these two quantities relied only on combustion experiments or on statistical relations, since no direct signal had been obtained from in-situ observations.

  11. Hepatoblastoma Biology Using Isotope Ratio Mass Spectrometry: Utility of a Unique Technique for the Analysis of Oncological Specimens

    Directory of Open Access Journals (Sweden)

    Katarzyna Taran

    2016-07-01

    Full Text Available Introduction: Hepatoblastoma is the most common primary liver tumor in children. However, it occurs rarely, with an incidence of 0.5-1.5 cases per million children. There is no clear explanation of the relationship between clinicopathologic features, therapy, and outcome in hepatoblastoma cases, so far. One of the most widely accepted prognostic factors in hepatoblastoma is histology of the tumor. The aim of the study was to determine the potential differences in biology of hepatoblastoma histological subtypes at the atomic level using the unique method of isotope ratio mass spectrometry, which is especially valuable in examination of small groups of biological samples.Material/Methods: Twenty-four measurements of nitrogen stable isotope ratio, carbon stable isotope ratio and total carbon to nitrogen mass ratio in fetal and embryonal hepatoblastoma tissue were performed using a Sercon 20-22 Continuous Flow Isotope Ratio Mass Spectrometer (CF-IRMS coupled with a Sercon SL elemental analyzer for simultaneous carbon-nitrogen-sulfur (NCS analysis.Results: A difference of about 1.781‰ in stable nitrogen isotope 15N/14N ratio was found between examined hepatoblastoma histological subtypes.Conclusions: The prognosis in liver tumors cases in children may be challenging particularly because of the lack of versatile methods of its evaluation. Isotope ratio mass spectrometry allows one to determine the difference between hepatoblastoma histological subtypes and clearly indicates the cases with the best outcome.

  12. Maintaining high precision of isotope ratio analysis over extended periods of time.

    Science.gov (United States)

    Brand, Willi A

    2009-06-01

    Stable isotope ratios are reliable and long lasting process tracers. In order to compare data from different locations or different sampling times at a high level of precision, a measurement strategy must include reliable traceability to an international stable isotope scale via a reference material (RM). Since these international RMs are available in low quantities only, we have developed our own analysis schemes involving laboratory working RM. In addition, quality assurance RMs are used to control the long-term performance of the delta-value assignments. The analysis schemes allow the construction of quality assurance performance charts over years of operation. In this contribution, the performance of three typical techniques established in IsoLab at the MPI-BGC in Jena is discussed. The techniques are (1) isotope ratio mass spectrometry with an elemental analyser for delta(15)N and delta(13)C analysis of bulk (organic) material, (2) high precision delta(13)C and delta(18)O analysis of CO(2) in clean-air samples, and (3) stable isotope analysis of water samples using a high-temperature reaction with carbon. In addition, reference strategies on a laser ablation system for high spatial resolution delta(13)C analysis in tree rings is exemplified briefly.

  13. Stable isotope ratio determination of the origin of vanillin in vanilla extracts and its relationship to vanillin/potassium ratios

    International Nuclear Information System (INIS)

    Martin, G.E.; Alfonso, F.C.; Figert, D.M.; Burggraff, J.M.

    1981-01-01

    A method is described for isolating vanillin from vanilla extract, followed by stable isotope ratio analysis to determine the amount of natural vanillin contained in adulterated vanilla extracts. After the potassium content is determined, the percent Madagascar and/or Java vanilla beans incorporated into the extract may then be approximated from the vanillin/potassium ratio

  14. Lead contamination in cocoa and cocoa products: isotopic evidence of global contamination.

    Science.gov (United States)

    Rankin, Charley W; Nriagu, Jerome O; Aggarwal, Jugdeep K; Arowolo, Toyin A; Adebayo, Kola; Flegal, A Russell

    2005-10-01

    In this article we present lead concentrations and isotopic compositions from analyses of cocoa beans, their shells, and soils from six Nigerian cocoa farms, and analyses of manufactured cocoa and chocolate products. The average lead concentration of cocoa beans was cocoa and chocolate products were as high as 230 and 70 ng/g, respectively, which are consistent with market-basket surveys that have repeatedly listed lead concentrations in chocolate products among the highest reported for all foods. One source of contamination of the finished products is tentatively attributed to atmospheric emissions of leaded gasoline, which is still being used in Nigeria. Because of the high capacity of cocoa bean shells to adsorb lead, contamination from leaded gasoline emissions may occur during the fermentation and sun-drying of unshelled beans at cocoa farms. This mechanism is supported by similarities in lead isotopic compositions of cocoa bean shells from the different farms (206Pb/207Pb = 1.1548-1.1581; 208Pb/207Pb = 2.4344-2.4394) with those of finished cocoa products (206Pb/207Pb = 1.1475-1.1977; 208Pb/207Pb = 2.4234-2.4673). However, the much higher lead concentrations and larger variability in lead isotopic composition of finished cocoa products, which falls within the global range of industrial lead aerosols, indicate that most contamination occurs during shipping and/or processing of the cocoa beans and the manufacture of cocoa and chocolate products.

  15. The relationship between carbon stable isotope ratios of hatchling down and egg yolk in Black-headed Gulls

    NARCIS (Netherlands)

    Klaassen, M.R.J.; Baarspul, T.; Dekkers, T.; Van Tienen, P.

    2004-01-01

    We reconstructed the nutrient source for egg synthesis by sampling Black-headed Gull (Larus ridibundus) eggs for yolk, analyzing their carbon stable isotope ratio, and comparing that to hatchling down. Most of the variation in carbon stable isotope ratio was explained by differences between nests,

  16. Stable carbon and nitrogen isotope ratios of sodium and potassium cyanide as a forensic signature.

    Science.gov (United States)

    Kreuzer, Helen W; Horita, Juske; Moran, James J; Tomkins, Bruce A; Janszen, Derek B; Carman, April

    2012-01-01

    Sodium and potassium cyanide are highly toxic, produced in large amounts by the chemical industry, and linked to numerous high-profile crimes. The U.S. Centers for Disease Control and Prevention has identified cyanide as one of the most probable agents to be used in a chemical terrorism event. We investigated whether stable C and N isotopic content of sodium and potassium cyanide could serve as a forensic signature for sample matching, using a collection of 65 cyanide samples. Upon analysis, a few of the cyanide samples displayed nonhomogeneous isotopic content associated with degradation to a carbonate salt and loss of hydrogen cyanide. Most samples had highly reproducible isotope content. Of the 65 cyanide samples, >95% could be properly matched based on C and N isotope ratios, with a false match rate <3%. These results suggest that stable C and N isotope ratios are a useful forensic signature for matching cyanide samples. © 2011 American Academy of Forensic Sciences.

  17. The measurement of the chemically mobile fraction of lead in soil using isotopic dilution analysis

    International Nuclear Information System (INIS)

    Kirchhoff, J.; Brand, J.; Schuettelkopf, H.

    1992-12-01

    The chemically available fraction of lead in eight soils measured by isotopic dilution analysis using 212 Pb ranged from 7 to 16% of the total content of lead in soil. The soluble fractions achieved values up to 63% of the total content in 1 M NH 4 NO 3 , 1 M MgCl 2 and 0.05 M DTPA solutions. Increasing the contact time between water and soil, the water-soil ratio from 1:1 to 5:1 and increasing the temperature of the soil-water suspension raised the chemically available fraction in soil. Comparing various soil parameters and the mobile fraction of lead, only pH shows a significant correlation. The amphoteric character of lead causes a minimum of mobility about pH 6; pH-values below are responsible for the higher mobility of lead as Pb 2+ , at pH-values above 6 soluble hydroxy and humic acid complexes are formed. (orig.) [de

  18. Dating of oilfield contamination by Natural Occurring Radioactive Materials (NORM) using isotopic ratios

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Othman, I.; Aba, A.

    2008-05-01

    In the present work, the possibility of using radium isotope ratios (226, 224, 228) for dating of NORM contaminated sites in the oilfields due to uncontrolled disposal of produced water into the environmental NORM contaminated soil sample were collected from different locations in Syrian Oilfields and radioactivity analysed. In addition, production water samples were collected and analysed to determine the isotopes ratios of the naturally occurring radioactive materials. The results have shown that the 228 Ra/ 226 Ra can be successfully used to date contaminated soil provided that this ratio is determined in production water. Moreover, the 210 Pb/ 226 Ra activity ratios was used for the first time for dating of contaminated soil where all factors affecting the method application have been evaluated. Furthermore, the obtained results for dating using the three methods were compared with the actual contamination dates provided by the oil companies. (Authors)

  19. Isotope ratio analysis by a combination of element analyzer and mass spectrometer

    International Nuclear Information System (INIS)

    Pichlmayer, F.

    1987-06-01

    The use of stable isotope ratios of carbon, nitrogen and sulfur as analytical tool in many fields of research is of growing interest. A method has therefore been developed, consisting in essential of coupling an Elemental Analyzer with an Isotope Mass Spectrometer, which enables the gas preparation of carbon dioxide, nitrogen and sulfur dioxide from any solid or liquid sample in a fast and easy way. Results of carbon isotope measurements in food analysis are presented, whereat it is possible to check origin and treatment of sugar, oils, fats, mineral waters, spirituous liquors etc. and to detect adulterations as well. Also applications in the field of environmental research are given. (Author)

  20. Hydrogen isotope ratios of mouse tissues are influenced by a variety of factors other than diet

    International Nuclear Information System (INIS)

    DeNiro, M.J.; Epstein, S.

    1981-01-01

    Hydrogen isotopes are fractionated during biochemical reactions in a variety of organisms. A number of experiments have shown that the D/H ratios of animals and their tissues are not controlled solely by the D/H ratios of their food. The authors performed a simple experiment which indicated that the D/H ratios of a significant fraction of the organically bonded hydrogen in animal tissues must be determined by the isotopic composition of water that the samples encounter. Aliquots of dried mouse brain and liver and mouse food were exposed to water vapors of different D/H ratios prior to isotopic analysis. The results of the experiment showed that at least 16 percent of the hydrogen in mouse brain is exchangeable with the hydrogen of water; the corresponding values for mouse liver and mouse food were 25 to 29 percent

  1. Mass spectrometric determination of magnesium isotopic ratios and its corrections for electron multiplier discrimination and mass fractionation

    International Nuclear Information System (INIS)

    Deng Zhongguo

    1989-01-01

    The mass spectrometric determination of magnesium isotopic ratios by the use of uranyl nitrate added to magnesium samples to act as a binding agent is reported. Prebaking empty filaments and preheating filaments with deposited magnesium samples on its surface in a vacuum are employed to reduce the Na signal from the thenium-ribbon. Methods for correcting magnesium isotopic ratios for electron multiplier discrimination and mass fractionation are described in detail. The results of the determination of natural magnesium isotopic ratios are 25 Mg/ 24 Mg = 0.12660 (1±0.01%) and 26 Mg/ 24 Mg = 0.13938 (1±0.10%). The magnesium isotopic ratios of rich - 26 Mg-2 sample and rich- 25 Mg-1 sample are 24 Mg/ 26 Mg = 0.003463 (1±0.2%), 25 Mg/ 26 Mg = 0.001656 (±0.2%) and 24 Mg/ 25 Mg = 0.006716 (1±0.2%), 26 Mg/ 25 Mg = 0.007264 (1±0.2%) respectively

  2. A new sniffer probe for the determination of hydrogen isotope ratios in the W7-AS stellarator

    Science.gov (United States)

    Zebisch, P.; Taglauer, E.

    1999-07-01

    An improved sniffer probe was constructed for measurements of the hydrogen isotope ratio and impurities in the plasma edge of the W7-AS stellarator. Details of the new design and the probe performance are presented. The new design allows changing the head without breaking the vacuum in the torus. It has a high mechanical stability, effective screening of the magnetic field and high sensitivity. The gas dynamic properties of the probe are analyzed using transmission line calculus, resulting in a rise time of 114 ms for hydrogen. During the 1997 spring measurement campaign, H/D isotope ratio measurements were carried through showing considerable outgassing of the walls during and after the discharge. He glow discharges reduce the isotope ratio drastically. Results from a typical experiment day are presented together with the analytic procedure for determining the isotope ratio in both the plasma edge and in the neutral gas region between the plasma and the vessel walls.

  3. Stable isotope ratio mass spectrometry and physical comparison for the forensic examination of grip-seal plastic bags.

    Science.gov (United States)

    Taylor, Erica; Carter, James F; Hill, Jenny C; Morton, Carolyn; Daeid, Niamh Nic; Sleeman, Richard

    2008-05-20

    Plastic bags are frequently used to package drugs, explosives and other contraband. There exists, therefore, a requirement in forensic casework to compare bags found at different locations. This is currently achieved almost exclusively by the use of physical comparisons such as birefringence patterns. This paper discusses some of the advantages and shortcomings of this approach, and presents stable isotope ratio mass spectrometry (IRMS) as a supplementary tool for effecting comparisons of this nature. Carbon and hydrogen isotopic data are presented for sixteen grip-seal plastic bags from a wide range of sources, in order to demonstrate the range of values which is likely to be encountered. Both isotopic and physical comparison (specifically birefringence) techniques are then applied to the analysis of rolls of bags from different manufacturing lots from a leading manufacturer. Both approaches are able to associate bags from a common production batch. IRMS can be applied to small fragments which are not amenable to physical comparisons, and is able to discriminate bags which could be confused using birefringence patterns alone. Similarly, in certain cases birefringence patterns discriminate bags with similar isotopic compositions. The two approaches are therefore complementary. When more than one isotopically distinct region exists within a bag (e.g. the grip-seal is distinct from the body) the ability to discriminate and associate bags is greatly increased.

  4. Effectiveness of different pre-treatments in recovering pre-burial isotopic ratios of charred plants.

    Science.gov (United States)

    Brinkkemper, O; Braadbaart, F; van Os, B; van Hoesel, A; van Brussel, A A N; Fernandes, R

    2018-02-15

    Isotopic analysis of archaeological charred plant remains offers useful archaeological information. However, adequate sample pre-treatment protocols may be necessary to provide a contamination-free isotopic signal while limiting sample loss and achieving a high throughput. Under these constraints, research was undertaken to compare the performance of different pre-treatment protocols. Charred archaeological plant material was selected for isotopic analysis (δ 13 C and δ 15 N values) by isotope ratio mass spectrometry from a variety of plant species, time periods and soil conditions. Preservation conditions and the effectiveness of cleaning protocols were assessed through Fourier transform infrared spectroscopy and X-ray fluorescence (XRF) spectrometry. An acid-base-acid protocol, successfully employed in radiocarbon dating, was used to define a contamination-free isotopic reference. Acid-base-acid isotopic measurements were compared with those obtained from untreated material and an acid-only protocol. The isotopic signals of untreated material and the acid-only protocol typically did not differ more than 1‰ from those of the acid-base-acid reference. There were no significant isotopic offsets between acid-base-acid and acid-only or untreated samples. Sample losses in the acid-base-acid protocol were on average 50 ± 17% (maximum = 98.4%). Elemental XRF measurements showed promising results in the detection of more contaminated samples albeit with a high rate of false positives. For the large range of preservation conditions described in the study, untreated charred plant samples, water cleaned of sediments, provide reliable stable isotope ratios of carbon and nitrogen. The use of pre-treatments may be necessary under different preservation conditions or more conservative measurement uncertainties should be reported. Copyright © 2017 John Wiley & Sons, Ltd.

  5. Isotopic ratio measurement using a double focusing magnetic sector mass analyser with an inductively coupled plasma as an ion source

    International Nuclear Information System (INIS)

    Walder, A.J.; Freedman, P.A.

    1992-01-01

    An inductively coupled plasma source was coupled to a magnetic sector mass analyser equipped with seven Faraday detectors. An electrostatic filter located between the plasma source and the magnetic sector was used to create a double focusing system. Isotopic ratio measurements of uranium and lead standards revealed levels of internal and external precision comparable to those obtained using thermal inonization mass spectrometry. An external precision of 0.014% was obtained from the 235 U: 238 U measurement of six samples of a National Bureau of Standards (NBS) Standard Reference Material (SRM) U-500, while an RSD of 0.022% was obtained from the 206 Pb: 204 Pb measurement of six samples of NBS SRM Pb-981. Measured isotopic ratios deviated from the NBS value by approximately 0.9% per atomic mass unit. This deviation approximates to a linear function of mass bias and can therefore be corrected for by the analysis of standards. The analysis of NBS SRM Sr-987 revealed superior levels of internal and external precision. The normalization of the 87 Sr: 86 Sr ratio to the 86 Sr: 88 Sr ratio reduced the RSD to approximately 0.008%. The measured ratio was within 0.01% of the NBS value and the day-to-day reproducibility was consistent within one standard deviation. (author)

  6. ICP-MS for isotope ratio measurement

    Science.gov (United States)

    The use of stable isotopes in mineral nutrition research has become a fundamental aspect of conducting this research. A gradual transition has occurred, now virtually complete, from radioactive isotope studies to those using stable isotopes. Although primarily used in human research, mineral stable ...

  7. Use of Pb and Sr isotopes on the determination of lead mineralization sources from Ribeira valley - Sao Paulo and Parana states

    International Nuclear Information System (INIS)

    Tassinari, C.C.G.; Barbour, A.P.; Sato, K.; Daitx, E.C.

    1990-01-01

    A lead and strontium isotope study was carried out on galena, barite and calcite from Pb-Ag syngenetic stratiform (Perau type) and hydrothermal veins (Panela type) deposits from Vale do Ribeira region (Sao Paulo and Parana states). The leads from the Perau and Panelas type deposits have respectively isotope ratios (sup(206)Pb/ sup(204)Pb 16.157 to 16.505 amd 16.520 to 17.273; sup(207)Pb/ sup(204)Pb = 15.466 to 15.720 and 15.470 to 15.780 and sup(208)Pb/ sup(204)Pb = 36.370 to 36.763 and 37.043 to 38.243), that defined a Stacey and Kramers model ages mainly concentrate within 1.7-1.5Ga. A review of published Pb isotopic compositions for these deposits and considerations of new Sr isotope data and Pb results using plumbotectonics model, indicate that the Perau type mineralizations are related to the syngenetic process and the Pb are derived from upper crust with a short crustal residence time. For the Panelas type deposits the Pb and Sr isotope studies support the conclusion that the ores were emplaced during regional metamorphism and the Pb were derived from lithologically complex source which may include metasedimentary and basement rocks. (author)

  8. ICP-MS as the method of the determination of gallium, indium and thallium isotope ratios in the studies of isotope effects in the chromatography systems

    International Nuclear Information System (INIS)

    Herdzik, I.

    2006-01-01

    The procedure of the determination of gallium, indium and thallium isotope ratios and its application to the studies of the isotope effects in chromatography systems by the ICP-MS method (inductively coupled plasma-mass spectrometry) are presented. It was shown that it is possible to determine the isotope ratios of gallium ( 69/71 Ga), indium ( 113/115 In) and thallium ( 203/205 Tl) with the relative standard deviation 0.03-0.07%. Such precision appeared to be sufficient to calculate the unit separation factors in the column chromatographic processes. (author) [pl

  9. A review on the determination of isotope ratios of boron with mass spectrometry.

    Science.gov (United States)

    Aggarwal, Suresh Kumar; You, Chen-Feng

    2017-07-01

    The present review discusses different mass spectrometric techniques-viz, thermal ionization mass spectrometry (TIMS), inductively coupled plasma mass spectrometry (ICPMS), and secondary ion mass spectrometry (SIMS)-used to determine 11 B/ 10 B isotope ratio, and concentration of boron required for various applications in earth sciences, marine geochemistry, nuclear technology, environmental, and agriculture sciences, etc. The details of the techniques-P-TIMS, which uses Cs 2 BO 2 + , N-TIMS, which uses BO 2 - , and MC-ICPMS, which uses B + ions for bulk analysis or B - and B + ions for in situ micro-analysis with SIMS-are highlighted. The capabilities, advantages, limitations, and problems in each mass spectrometric technique are summarized. The results of international interlaboratory comparison experiments conducted at different times are summarized. The certified isotopic reference materials available for boron are also listed. Recent developments in laser ablation (LA) ICPMS and QQQ-ICPMS for solids analysis and MS/MS analysis, respectively, are included. The different aspects of sample preparation and analytical chemistry of boron are summarized. Finally, the future requirements of boron isotope ratios for future applications are also given. Presently, MC-ICPMS provides the best precision and accuracy (0.2-0.4‰) on isotope ratio measurements, whereas N-TIMS holds the potential to analyze smallest amount of boron, but has the issue of bias (+2‰ to 4‰) which needs further investigations. © 2016 Wiley Periodicals, Inc. Mass Spec Rev 36:499-519, 2017. © 2016 Wiley Periodicals, Inc.

  10. Review: Current applications and challenges for liquid chromatography coupled to isotope ratio mass spectrometry (LC/IRMS).

    Science.gov (United States)

    Godin, Jean-Philippe; McCullagh, James S O

    2011-10-30

    High-precision isotope analysis is recognized as an essential research tool in many fields of study. Until recently, continuous flow isotope ratio mass spectrometry (CF-IRMS) was available via an elemental analyzer or a gas chromatography inlet system for compound-specific analysis of light stable isotopes. In 2004, however, an interface that coupled liquid chromatography with IRMS (LC/IRMS) became commercially available for the first time. This brought the capability for new areas of application, in particular enabling compound-specific δ(13)C analysis of non-volatile, aqueous soluble, compounds from complex mixtures. The interface design brought with it several analytical constraints, however, in particular a lack of compatibility with certain types of chromatography as well as limited flow rates and mobile phase compositions. Routine LC/IRMS methods have, however, been established for measuring the δ(13)C isotopic ratios of underivatized individual compounds for application in archeology, nutrition and physiology, geochemistry, hydrology, soil science and food authenticity. Seven years after its introduction, we review the technical advances and constraints, methodological developments and new applications of liquid chromatography coupled to isotope ratio mass spectrometry. Copyright © 2011 John Wiley & Sons, Ltd.

  11. Trace Metals and Lead Isotopes in modern Sediments Near Rio de Janeiro, Brazil

    Science.gov (United States)

    Boyle, E. A.; Lazzari, L.; Wagener, A. L.; Carreira, R.; Godoy, J. M.; Noble, A.; Carrasco, G. G.; Moos, S. B.

    2014-12-01

    This work focuses on the export of trace metals and combustion residues from land to ocean and on the Southeast continental margin of Brazil and its historical variability using stable lead isotopes. Two sediment cores were collected, one in highly impacted Guanabara Bay and the other on the Southeast continental shelf. Continental shelf samples were analyzed for trace element concentrations [Mn (117±50 ppm), Ni (6.5±2.3 ppm), Zn (5.0±1.5), (233±46 ppm), ], Pb (5.4±2.4 ppm), as well as Cu, Ag, Cd, Sr, Ba, Tl, U and Pb isotope ratios & Pb-210. Most of the elements show higher concentrations on the upper part of the core compared to the bottom. Downcore changes of the concentrations of these elements were similar. The sediments of adjacent rivers and bays around the upper section of the southeast continental shelf of Brazil are considered highly enriched with Pb, Zn, Cu and Cr such as Guanabara Bay, Sepetiba Bay and Paraíba do Sul River compared with the natural concentrations and other regions in the world. A [Pb] maximum is seen between samples from 24 to 43 cm (~8 ppm). Utilization of tetraethyl lead (TEL) gasoline in Brazil was phased out beginning in 1983 and was largely completed by 1988. Continental shelf Pb-206/Pb-207 varies between 1.174 near the core top to 1.190 at 100 cm, with a sharp difference between samples at 6 and 8 cm. Higher core top Pb, Zn, and Ni corroborate the recent anthropogenic influence on the southeast continental shelf of Brazil. For Guanabara Bay sediment samples [Pb] varies between 90 ppm near the top to 1 ppm at the bottom. Pb-206/Pb-207 varies between 1.161 near the core top to 1.165 near the bottom. Using triple isotope plots we can discern different sources of lead to the region and how these vary with time.

  12. Isotope ratio measurements of uranium by LA-HR-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Marin, Rafael C.; Sarkis, Jorge E.S., E-mail: rafael.marin@usp.b, E-mail: jesarkis@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    This work describes the utilization of Laser Ablation High Resolution Inductively Mass Spectrometry (LA-HR-ICP-MS) technique for the determination of uranium isotope composition in a UO{sub 2} pellet (CRM -125A) supplied and certified by the New Brunswick Laboratory (NBL). To carry out the adjustments of the parameters was used a glass standard NIST 610, supplied and certified by National Institute of Standards and Technology (NIST). The precision of the measurements were improved by adjusting the following parameters: RF power, laser beam diameter, defocusing of laser beam, laser energy, laser energy-density, auxiliary gas and sample gas. The measurements were performed on a continuous ablation with low energy density and defocusing, which demonstrated to be the optimum to reach the best signal stability. Isotope ratios, {sup 234}U/{sup 238}U, {sup 235}U/{sup 238}U and {sup 236}U/{sup 238}U were measured, reaching relative standard deviations (RSD) from 1.55% to 7.60%. The parameters which caused the greatest impact in order to improve the signal stability were RF power, defocusing and laser beam diameter. The results presented by the measurements revealed that the Laser ablation ICP-MS technique offers a rapid and accurate way to perform uranium isotope ratios without any sample preparation, since it allows carrying out the measurements straight on the sample, besides to preserve the testimony that is very important for safeguards and nuclear forensics purposes. (author)

  13. Seasonal dynamics of stable isotopes and element ratios in authigenic calcites during their precipitation and dissolution, Sacrower See (northeastern Germany

    Directory of Open Access Journals (Sweden)

    Bernd ZOLITSCHKA

    2009-08-01

    Full Text Available The seasonal evolution of chemical and physical water properties as well as particle fluxes was monitored in Sacrower See (northeastern Germany during two consecutive years (Oct 2003 - Oct 2005. Additonally, we measured δ18O and δ13C as well as Sr:Ca and Mg:Ca ratios of authigenic calcites that were collected in sequencing sediment traps in order to disentangle environmental and climatic factors controlling these parameters. In particular, our aim was to find out if element ratios and the isotopic composition of calcites reflect changes in water and air temperatures. Lake water is highly enriched in 18O (-1.3 to -2.5‰ VSMOW with an evaporative increase of 0.6‰ during summer. Values are 5-6‰ more positive than groundwater values and 4-5‰ more positive than long-term weighted annual means of precipitation. During spring and summer, high amounts of dissolved phosphate cause eutrophic conditions and calcite precipitation in isotopic disequilibrium. Measured values are depleted in 18O by 2 to 10‰ compared to calculated equilibrium values. Resuspension and partial dissolution of calcite in the water column contribute to this isotopic divergence in summer and autumn as δ18Oca and δ13C values increased in the hypolimnion during this time. Mg:Ca and Sr:Ca ratios are altered by dissolution as well. In the hypolimnion these ratios were higher than in the epilimnion. Another reason for the huge deviation between measured and theoretical δ18Oca values during summer is the occurrence of large amounts of Phacotus lenticularis in the carbonate fraction. High amounts of Phacotus lead to more negative δ18Oca and more positive δ13C values. Several characteristics of δ18Oca and δ13C are also reflected by Mg:Ca and Sr:Ca ratios and isotopic composition of oxygen and carbon were influenced by the onset and stability of stratification. Especially the earlier onset of stratification in 2005 caused higher sediment fluxes and more positive carbon and

  14. High dynamic range isotope ratio measurements using an analog electron multiplier

    Czech Academy of Sciences Publication Activity Database

    Williams, P.; Lorinčík, Jan; Franzreb, K.; Herwig, R.

    2013-01-01

    Roč. 45, č. 1 (2013), s. 549-552 ISSN 0142-2421 R&D Projects: GA MŠk ME 894 Institutional support: RVO:67985882 Keywords : Isotope ratios * electron multiplier * dynamic range Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.393, year: 2013

  15. Identifying the change in atmospheric sulfur sources in China using isotopic ratios in mosses

    Science.gov (United States)

    Xiao, Hua-Yun; Tang, Cong-Guo; Xiao, Hong-Wei; Liu, Xue-Yan; Liu, Cong-Qiang

    2009-08-01

    A considerable number of studies on rainwater sulfur isotopic ratios (δ34Srain) have been conducted to trace sulfur sources at a large number of sites in the past. If longitudinal studies on the isotope composition of precipitation sulfate were conducted, it is possible to relate that to changes in sulfur emissions. But direct measurement needs considerable labor and time. So, in this study, sulfur isotopic ratios in rainwater and mosses were analyzed at Guiyang and Nanchang to evaluate the possibility of using mosses as a substitute for rainwater. We found that present moss sulfur isotopic ratios were comparable to those of present rainwater. Additionally, we investigated the changes of atmospheric sulfur sources and sulfur concentrations using an isotopic graphic analysis at five industrial cities, two forested areas, and two remote areas in China. Mosses in industrial cities show a wide range of δ34S values, with the highest occurring at Chongqing (+3.9‰) and the lowest at Guiyang (-3.1‰). But as compared to those in forested and remote areas, δ34S values of mosses in all the five industrial cities are lower. On the basis of isotopic comparisons between past rainwater (reported in the literature) and present mosses, in the plot of δ34Smoss versus δ34Srain, six zones indicating different atmospheric sulfur change are separated by the 1:1 line and δ34S values of potential sulfur sources. Our results indicate that atmospheric sulfur pollution in most of the industrial cities decreased, while at the two forested areas, no significant changes were observed, and a new anxiousness coming from new energy sources (e.g., oil) appeared in some cities. Studies on the change of ambient SO2 concentrations support these results.

  16. Quantifying Uranium Isotope Ratios Using Resonance Ionization Mass Spectrometry: The Influence of Laser Parameters on Relative Ionization Probability

    Energy Technology Data Exchange (ETDEWEB)

    Isselhardt, Brett H. [Univ. of California, Berkeley, CA (United States)

    2011-09-01

    Resonance Ionization Mass Spectrometry (RIMS) has been developed as a method to measure relative uranium isotope abundances. In this approach, RIMS is used as an element-selective ionization process to provide a distinction between uranium atoms and potential isobars without the aid of chemical purification and separation. We explore the laser parameters critical to the ionization process and their effects on the measured isotope ratio. Specifically, the use of broad bandwidth lasers with automated feedback control of wavelength was applied to the measurement of 235U/238U ratios to decrease laser-induced isotopic fractionation. By broadening the bandwidth of the first laser in a 3-color, 3-photon ionization process from a bandwidth of 1.8 GHz to about 10 GHz, the variation in sequential relative isotope abundance measurements decreased from >10% to less than 0.5%. This procedure was demonstrated for the direct interrogation of uranium oxide targets with essentially no sample preparation. A rate equation model for predicting the relative ionization probability has been developed to study the effect of variation in laser parameters on the measured isotope ratio. This work demonstrates that RIMS can be used for the robust measurement of uranium isotope ratios.

  17. Assessing connectivity of estuarine fishes based on stable isotope ratio analysis

    Science.gov (United States)

    Herzka, Sharon Z.

    2005-07-01

    Assessing connectivity is fundamental to understanding the population dynamics of fishes. I propose that isotopic analyses can greatly contribute to studies of connectivity in estuarine fishes due to the high diversity of isotopic signatures found among estuarine habitats and the fact that variations in isotopic composition at the base of a food web are reflected in the tissues of consumers. Isotopic analysis can be used for identifying nursery habitats and estimating their contribution to adult populations. If movement to a new habitat is accompanied by a shift to foods of distinct isotopic composition, recent immigrants and residents can be distinguished based on their isotopic ratios. Movement patterns thus can be reconstructed based on information obtained from individuals. A key consideration is the rate of isotopic turnover, which determines the length of time that an immigrant to a given habitat will be distinguishable from a longtime resident. A literature survey indicated that few studies have measured turnover rates in fishes and that these have focused on larvae and juveniles. These studies reveal that biomass gain is the primary process driving turnover rates, while metabolic turnover is either minimal or undetectable. Using a simple dilution model and biomass-specific growth rates, I estimated that young fishes with fast growth rates will reflect the isotopic composition of a new diet within days or weeks. Older or slower-growing individuals may take years or never fully equilibrate. Future studies should evaluate the factors that influence turnover rates in fishes during various stages of the life cycle and in different tissues, as well as explore the potential for combining stable isotope and otolith microstructure analyses to examine the relationship between demographic parameters, movement and connectivity.

  18. USE OF GC-MS/COMBUSTION/IRMS TO IDENTIFY AND DETERMINE THE STABLE CARBON ISOTOPIC RATIO OF INDIVIDUAL LIPIDS

    Science.gov (United States)

    A system that couples a gas chromatograph (GC) via a split to a quadrapole mass spectrometer (MS) and, through a combustion interface, to an isotope ratio mass spectrometer (IRMS) allows the simultaneous detection of electron impact mass spectra and stable carbon isotope ratio an...

  19. Method for determination of stable carbon isotope ratio of methylnitrophenols in atmospheric particulate matter

    Directory of Open Access Journals (Sweden)

    S. Moukhtar

    2011-11-01

    Full Text Available A technique for the measurement of the stable isotope ratio of methylnitrophenols in atmospheric particulate matter is presented. Atmospheric samples from rural and suburban areas were collected for evaluation of the procedure. Particulate matter was collected on quartz fibre filters using dichotomous high volume air samplers. Methylnitrophenols were extracted from the filters using acetonitrile. The sample was then purified using a combination of high-performance liquid chromatography and solid phase extraction. The final solution was then divided into two aliquots. To one aliquot, a derivatising agent, Bis(trimethylsilyltrifluoroacetamide, was added for Gas Chromatography-Mass Spectrometry analysis. The second half of the sample was stored in a refrigerator. For samples with concentrations exceeding 1 ng μl−1, the second half of the sample was used for measurement of stable carbon isotope ratios by Gas Chromatography-Isotope Ratio Mass Spectrometry.

    The procedure described in this paper provides a method for the analysis of methylnitrophenols in atmospheric particulate matter at concentrations as low as 0.3 pg m−3 and for stable isotope ratios with an accuracy of better than ±0.5‰ for concentrations exceeding 100 pg m−3.

    In all atmospheric particulate matter samples analysed, 2-methyl-4-nitrophenol was found to be the most abundant methylnitrophenol, with concentrations ranging from the low pg m−3 range in rural areas to more than 200 pg m−3 in some samples from a suburban location.

  20. Collinear laser spectroscopy on radioactive neutron-deficient lead and thallium isotopes

    International Nuclear Information System (INIS)

    Menges, R.

    1989-02-01

    The systematic study of the isotope shift in the neighbourhood of the closed shells was extended in this thesis to Z = 82. The elements lead and thallium were measured up to the mass 190 and 188 and the nuclear moments determined together with the change of the mean square charge radius. The accumulating of the recoil nuclei formed by heavy ion reactions in the bunched ion source of the GSI mass separator could be used in order to study the low-spin isomers with I = 2 of the neutron-deficient thallium isotopes up to A = 190. It is a clearly recognizable isomer shift against the I = 7 isomers shown which changes at A = 194 the sign. A phenomenon which also exists in the element mercury, but for which no sufficient explanation exists. The magnetic moments of the thallium isotopes complete the analysis of Ekstroem (1976) and confirm the choice of the sign of the magnetic moments of the I = 2 isomers. The application of the additivity rule to the odd-odd nuclei shows qualitatively good agreement with the experiment and confirms so the assignment of the configuration of the contributing nuclear states. The quadrupole moments show a slight oblate deformation of the 9/2 - intruder states. The moments of the lead isotopes show pronounced one-particle character and by this the nearly spherical shape of nuclei with closed proton shell. The deviation from the linear slope of the mean square radius of the lead isotopes onsetting at A = 194 cannot be explained by the mixing of the 0 1 + ground state with the deformed 0 2 + intruder state. The odd - even staggering and the buckling of the charge radii at the shell closure are very well reproduced by Hartree-Fock calculations which regard the 3- and 4-particle interactions in the nucleus. (orig.) [de

  1. Optimization of on-line hydrogen stable isotope ratio measurements of halogen- and sulfur-bearing organic compounds using elemental analyzer–chromium/high-temperature conversion isotope ratio mass spectrometry (EA-Cr/HTC-IRMS)

    Science.gov (United States)

    Gehre, Matthias; Renpenning, Julian; Geilmann, Heike; Qi, Haiping; Coplen, Tyler B.; Kümmel, Steffen; Ivdra, Natalija; Brand, Willi A.; Schimmelmann, Arndt

    2017-01-01

    Rationale: Accurate hydrogen isotopic analysis of halogen- and sulfur-bearing organics has not been possible with traditional high-temperature conversion (HTC) because the formation of hydrogen-bearing reaction products other than molecular hydrogen (H2) is responsible for non-quantitative H2 yields and possible hydrogen isotopic fractionation. Our previously introduced, new chromium-based EA-Cr/HTC-IRMS (Elemental Analyzer–Chromium/High-Temperature Conversion Isotope Ratio Mass Spectrometry) technique focused primarily on nitrogen-bearing compounds. Several technical and analytical issues concerning halogen- and sulfur-bearing samples, however, remained unresolved and required further refinement of the reactor systems.

  2. Graphite Isotope Ratio Method Development Report: Irradiation Test Demonstration of Uranium as a Low Fluence Indicator

    International Nuclear Information System (INIS)

    Reid, B.D.; Gerlach, D.C.; Love, E.F.; McNeece, J.P.; Livingston, J.V.; Greenwood, L.R.; Petersen, S.L.; Morgan, W.C.

    1999-01-01

    This report describes an irradiation test designed to investigate the suitability of uranium as a graphite isotope ratio method (GIRM) low fluence indicator. GIRM is a demonstrated concept that gives a graphite-moderated reactor's lifetime production based on measuring changes in the isotopic ratio of elements known to exist in trace quantities within reactor-grade graphite. Appendix I of this report provides a tutorial on the GIRM concept

  3. Stable carbon and oxygen isotope ratios of malachite from the patinas of ancient bronze objects

    International Nuclear Information System (INIS)

    Smith, A.W.

    1978-01-01

    13 C/ 12 C and 18 O/ 16 O ratios have been measured for 62 samples of the mineral malachite, taken from the patinas of ancient bronze objects (from Britain, Italy, Libya and China), in order to investigate any possible relationship which may exist between the isotope ratios and the burial conditions of the objects. The results indicate that the isotope ratios are controlled by complex factors related to the climate, vegetation and soil type at the burial site. It is suggested that the technique might be used, given favourable circumstances, in the characterization of patinas and as a possible aid in the detection of synthetic patination. (author)

  4. Isotope dilution inductively coupled plasma mass spectrometry (ID ICP-MS) for the certification of lead and cadmium in environmental standard reference materials.

    Science.gov (United States)

    Murphy, K E; Beary, E S; Rearick, M S; Vocke, R D

    2000-10-01

    Lead (Pb) and cadmium (Cd) have been determined in six new environmental standard reference materials (SRMs) using isotope dilution inductively coupled plasma mass spectrometry (ID ICP-MS). The SRMs are the following: SRM 1944, New York-New Jersey Waterway Sediment, SRMs 2583 and 2584, Trace Elements in Indoor Dust, Nominal 90 mg/kg and 10,000 mg/kg Lead, respectively, SRMs 2586 and 2587, Trace Elements in Soil Containing Lead from Paint, Nominal 500 mg/kg and 3,000 mg/kg Lead, respectively, and SRM 2782, Industrial Sludge. The capabilities of ID ICP-MS for the certification of Pb and Cd in these materials are assessed. Sample preparation and ratio measurement uncertainties have been evaluated. Reproducibility and accuracy of the established procedures are demonstrated by determination of gravimetrically prepared primary standard solutions and by comparison with isotope dilution thermal ionization mass spectrometry (ID TIMS). Material heterogeneity was readily demonstrated to be the dominant source of uncertainty in the certified values.

  5. Lead and Stable Isotopes in Sediments of Babitonga Bay: An Oil Spill Case

    Energy Technology Data Exchange (ETDEWEB)

    Barrosa, V. G.; Oliveiraa, T. M.N.; Vaza, C. [University of UNIVILLE, Department of Environmental Engineering, Joinville, Santa Catarina (Brazil); Zuppi, G. M. [Dipartimento di Scienze Molecolari e Nanosistemi Universita Ca' Foscari, Venezia and Institute of Environmental Geology and Geoengineering, National Research Council, Monterotondo (Italy)

    2013-07-15

    The hydrologic complex of Babitonga Bay (Brazil) forms a vast environmental complex, hosting the last great mangrove bulk of the southern hemisphere. Mangroves are among the most productive ecosystems on earth. The effects of an oil spill were studied in Babitonga Bay using lead and carbon isotopes. Samples of the spilled oil were obtained nine months after the accident, as well as sediment and water samples. Thus, the isotopic composition of the oil allowed the tracing of the environmental pollution. Notwithstanding the delay in time, isotopes of lead and carbon allowed the identification of areas where the presence of the oil can be still detected, permitting assessment of the extent of pollution. Contaminated sediments exhibited an isotopic composition ({sup 206}Pb/{sup 207}Pb and {sup 208}Pb/{sup 206}Pb) close to that of the oil spilled. Moreover {delta}{sup 13}C also permitted the ratification of these results. Others isotopes were used but with no contributions. Conclusions are derived in terms of the source of the pollution in the specific area. (author)

  6. Long-Term Precipitation Isotope Ratios (δ18O, δ2H, d-excess) in the Northeast US Reflect Atlantic Ocean Warming and Shifts in Moisture Sources

    Science.gov (United States)

    Puntsag, T.; Welker, J. M.; Mitchell, M. J.; Klein, E. S.; Campbell, J. L.; Likens, G.

    2014-12-01

    The global water cycle is exhibiting dramatic changes as global temperatures increase resulting in increases in: drought extremes, flooding, alterations in storm track patterns with protracted winter storms, and greater precipitation variability. The mechanisms driving these changes can be difficult to assess, but the spatial and temporal patterns of precipitation water isotopes (δ18O, δ2H, d-excess) provide a means to help understand these water cycle changes. However, extended temporal records of isotope ratios in precipitation are infrequent, especially in the US. In our study we analyzed precipitation isotope ratio data from the Hubbard Brook Experimental Forest in New Hampshire that has the longest US precipitation isotope record, to determine: 1) the monthly composited averages and trends from 1967 to 2012 (45 years); ; 2) the relationships between abiotic properties such as local temperatures, precipitation type, storm tracks and isotope ratio changes; and 3) the influence of regional shifts in moisture sources and/or changes in N Atlantic Ocean water conditions on isotope values. The seasonal variability of Hubbard Brook precipitation isotope ratios is consistent with other studies, as average δ18O values are ~ -15‰ in January and ~ -5 ‰ in July. However, over the 45 year record there is a depletion trend in the δ 18O values (becoming isotopically lighter with a greater proportion of 16O), which coupled with less change in δ 2H leads to increases in d-excess values from ~ -10‰ around 1970 to greater than 10‰ in 2009. These changes occurred during a period of warming as opposed to cooling local temperatures indicating other processes besides temperature are controlling long-term water isotope traits in this region. We have evidence that these changes in precipitation isotope traits are controlled in large part by an increases in moisture being sourced from a warming N Atlantic Ocean that is providing evaporated, isotopically

  7. VizieR Online Data Catalog: C and O isotopic ratios in Arcturus and Aldebaran (Abia+ 2012)

    Science.gov (United States)

    Abia, C.; Palmerini, S.; Busso, M.; Cristallo, S.

    2012-10-01

    CNO abundances, C and O isotopic ratios and equivalent diffusive coefficients (D) are given for the calculated extra-mixing models. For Arcturus we used the electronic version of the Infrared Atlas Spectrum by Hinkle et al. (1995, Cat. J/PASP/107/1042; resolution 0.01cm-1), and for Aldebaran we used a spectrum obtained on February 6, 1980 at the KPNO 4m Coude telescope using a Fourier transform spectrometer, kindly provided by K. Hinkle (resolution 0.016cm-1) The first 2 rows of table4 report the CNO abundances and isotopic ratios resulting from the observations. The other rows give the CNO abundances and isotopic ratios accounted for by the FDU in the three stellar models considered of 1.3Mo, 1.2Mo and 1.08Mo (see the paper for more details). (1 data file).

  8. Preliminary study of lead isotopes in the carbonate-silica veins of Trench 14, Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    Zartman, R.E.; Kwak, L.M.

    1993-01-01

    The sub-vertical carbonate-silica veins filling the Bow Ridge Fault, where exposed in Trench 14 on the east side of Yucca Mountain, carry a lead isotopic signature that can be explained in terms of local sources. Two isotopically distinguishable--silicate and carbonate--fractions of lead are recognized within the vein system as well as in overlying surficial calcrete deposits. The acid-insoluble silicate fraction is contributed largely from the decomposing Miocene volcanic tuff, which forms the wall rock of the fault zone and is a ubiquitous component of the overlying soil. Lead contained in the silicate fraction approaches in isotopic composition that of the Miocene volcanic rocks of Yucca Mountain, but diverges from it in some samples by being more enriched in uranogenic isotopes. The carbonate fraction of lead in both vein and calcrete samples resides dominantly in the HCl- and CH 3 COOH-soluble calcite. HCl evidently also attacks and removes lead from silicate phases, but the milder CH 3 COOH dissolution procedure oftentimes identifies a significantly more radiogenic lead in the calcite. Wind-blown particulate matter brought to the area from Paleozoic and Late Proterozoic limestones in surrounding mountains may be the ultimate source of the calcite. Isotopically more uniform samples suggest that locally the basaltic ash and other volcanic rock have contributed most of the lead to both fractions of the vein system. An important finding of this study is that the data does not require the more exotic mechanisms or origins that have been proposed for the veins. Instead, the remarkably similar lead isotopic properties of the veins to those of the soil calcretes support their interpretation as a surficial, pedogenic phenomenon

  9. Spectrum analysis in lead spectrometer for isotopic fissile assay in used fuel

    International Nuclear Information System (INIS)

    Lee, Y.D.; Park, C.J.; Kim, H.D.; Song, K.C.

    2014-01-01

    The LSDS system is under development for analyzing isotopic fissile content applicable in a hot cell for the pyro process. The fuel assay area and nuclear material composition were selected for simulation. The source mechanism for efficient neutron generation was also determined. A neutron is produced at the Ta target by hitting it from accelerated electron. The parameters for an electron accelerator are being researched for cost effectiveness, easy maintenance, and compact size. The basic principle of LSDS is that isotopic fissile has its own fission structure below the unresolved resonance region. The source neutron interacts with a lead medium and produces continuous neutron energy, which generates dominant fission at each fissile. Therefore, a spectrum analysis is very important at a lead medium and fuel area for system working. The energy spectrum with respect to slowing down energy and the energy resolution were investigated in lead. A spectrum analysis was done by the existence of surrounding detectors. In particular, high resonance energy was considered. The spectrum was well organized at each slowing down energy and the energy resolution was acceptable to distinguish isotopic fissile fissions. Additionally, LSDS is applicable for the optimum design of spent fuel storage and management.The isotopic fissile content assay will increase the transparency and credibility for spent fuel storage and its re-utilization, as demanded internationally. (author)

  10. Calibration and Data Processing in Gas Chromatography Combustion Isotope Ratio Mass Spectrometry

    Science.gov (United States)

    Zhang, Ying; Tobias, Herbert J.; Sacks, Gavin L.; Brenna, J. Thomas

    2013-01-01

    Compound-specific isotope analysis (CSIA) by gas chromatography combustion isotope ratio mass spectrometry (GCC-IRMS) is a powerful technique for the sourcing of substances, such as determination of the geographic or chemical origin of drugs and food adulteration, and it is especially invaluable as a confirmatory tool for detection of the use of synthetic steroids in competitive sport. We review here principles and practices for data processing and calibration of GCC-IRMS data with consideration to anti-doping analyses, with a focus on carbon isotopic analysis (13C/12C). After a brief review of peak definition, the isotopologue signal reduction methods of summation, curve-fitting, and linear regression are described and reviewed. Principles for isotopic calibration are considered in the context of the Δ13C = δ13CM – δ13CE difference measurements required for establishing adverse analytical findings for metabolites relative to endogenous reference compounds. Considerations for the anti-doping analyst are reviewed. PMID:22362612

  11. Evaluation of the combined measurement uncertainty in isotope dilution by MC-ICP-MS

    International Nuclear Information System (INIS)

    Fortunato, G.; Wunderli, S.

    2003-01-01

    The combination of metrological weighing, the measurement of isotope amount ratios by a multicollector inductively coupled plasma mass spectrometer (MC-ICP-MS) and the use of high-purity reference materials are the cornerstones to achieve improved results for the amount content of lead in wine by the reversed isotope dilution technique. Isotope dilution mass spectrometry (IDMS) and reversed IDMS have the potential to be a so-called primary method, with which close comparability and well-stated combined measurement uncertainties can be obtained. This work describes the detailed uncertainty budget determination using the ISO-GUM approach. The traces of lead in wine were separated from the matrix by ion exchange chromatography after HNO 3 /H 2 O 2 microwave digestion. The thallium isotope amount ratio (n( 205 Tl)/n( 203 Tl)) was used to correct for mass discrimination using an exponential model approach. The corrected lead isotope amount ratio n( 206 Pb)/n( 208 Pb) for the isotopic standard SRM 981 measured in our laboratory was compared with ratio values considered to be the least uncertain. The result has been compared in a so-called pilot study ''lead in wine'' organised by the CCQM (Comite Consultatif pour la Quantite de Matiere, BIPM, Paris; the highest measurement authority for analytical chemical measurements). The result for the lead amount content k(Pb) and the corresponding expanded uncertainty U given by our laboratory was:k(Pb)=1.329 x 10-10mol g-1 (amount content of lead in wine)U[k(Pb)]=1.0 x 10-12mol g-1 (expanded uncertainty U=k x uc, k=2) The uncertainty of the main influence parameter of the combined measurement uncertainty was determined to be the isotope amount ratio R 206,B of the blend between the enriched spike and the sample. (orig.)

  12. The measurement of mass spectrometric peak height ratio of helium isotope in trace samples

    International Nuclear Information System (INIS)

    Sun Mingliang

    1989-01-01

    An experiment study on the measurement of mass spectrometric peak height ratio of helium isotope in the trace gaseous sample is discussed by using the gas purification line designed by the authors and model VG-5400 static-vacuum noble gas mass spectrometer imported and air helium as a standard. The results show that the amount of He and Ne in natural gas sample is 99% after purification. When the amount of He in Mass Spectrometer is more than 4 x 10 -7 cm 3 STP, it's sensitivity remains stable, about 10 -4 A/cm 3 STP He and the precision of 3 He/ 4 He ratio within the following 17 days is 1.32%. The 'ABA' pattern and experiment condition in the measurement of mass spectrometric peak height ratio of He isotope are presented

  13. CARBON AND OXYGEN ISOTOPIC RATIOS FOR NEARBY MIRAS

    Energy Technology Data Exchange (ETDEWEB)

    Hinkle, Kenneth H. [National Optical Astronomy Observatory P.O. Box 26732, Tucson, AZ 85726 (United States); Lebzelter, Thomas [Department of Astrophysics, University of Vienna Türkenschanzstrasse 17, A-1180 Vienna (Austria); Straniero, Oscar, E-mail: khinkle@noao.edu, E-mail: thomas.lebzelter@univie.ac.at, E-mail: straniero@oa-teramo.inaf.it [INAF, Osservatorio Astronomico di Collurania I-64100 Teramo (Italy)

    2016-07-01

    Carbon and oxygen isotopic ratios are reported for a sample of 46 Mira and SRa-type variable asymptotic giant branch (AGB) stars. Vibration–rotation first and second-overtone CO lines in 1.5–2.5 μ m spectra were measured to derive isotopic ratios for {sup 12}C/{sup 13}C, {sup 16}O/{sup 17}O, and {sup 16}O/{sup 18}O. Comparisons with previous measurements for individual stars and with various samples of evolved stars, as available in the extant literature, are discussed. Models for solar composition AGB stars of different initial masses are used to interpret our results. We find that the majority of M-stars have main sequence masses ≤2 M {sub ⊙} and have not experienced sizable third dredge-up (TDU) episodes. The progenitors of the four S-type stars in our sample are slightly more massive. Of the six C-stars in the sample three have clear evidence relating their origin to the occurrence of TDU. Comparisons with O-rich presolar grains from AGB stars that lived before the formation of the solar system reveal variations in the interstellar medium chemical composition. The present generation of low-mass AGB stars, as represented by our sample of long period variables (LPVs), shows a large spread of {sup 16}O/{sup 17}O ratios, similar to that of group 1 presolar grains and in agreement with theoretical expectations for the composition of mass 1.2–2 M {sub ⊙} stars after the first dredge-up. In contrast, the {sup 16}O/{sup 18}O ratios of present-day LPVs are definitely smaller than those of group 1 grains. This is most probably a consequence of the the decrease with time of the {sup 16}O/{sup 18}O ratio in the interstellar medium due to the chemical evolution of the Milky Way. One star in our sample has an O composition similar to that of group 2 presolar grains originating in an AGB star undergoing extra-mixing. This may indicate that the extra-mixing process is hampered at high metallicity, or, equivalently, favored at low metallicity. Similarly to O

  14. Identification of the sources of metal (lead) contamination in drinking waters in north-eastern Tasmania using lead isotopic compositions.

    Science.gov (United States)

    Harvey, P J; Handley, H K; Taylor, M P

    2015-08-01

    This study utilises a range of scientific approaches, including lead isotopic compositions, to differentiate unknown sources of ongoing lead contamination of a drinking water supply in north-eastern Tasmania, Australia. Drinking water lead concentrations are elevated above the Australian Drinking Water Guideline (10 μg/L), reaching 540 μg/L in the supply network. Water lead isotopic compositions from the town of Pioneer ((208)Pb/(207)Pb 2.406, (206)Pb/(207)Pb 1.144 to (208)Pb/(207)Pb 2.360, (206)Pb/(207)Pb 1.094) and Ringarooma ((208)Pb/(207)Pb 2.398, (206)Pb/(207)Pb 1.117) are markedly different from the local bedrock ((208)Pb/(207)Pb 2.496, (206)Pb/(207)Pb 1.237). The data show that the lead in the local waters is sourced from a combination of dilapidated drinking water infrastructure, including lead jointed pipelines, end-of-life polyvinyl chloride pipes and household plumbing. Drinking water is being inadvertently contaminated by aging infrastructure, and it is an issue that warrants investigation to limit the burden of disease from lead exposure.

  15. Performance evaluation of nitrogen isotope ratio determination in marine and lacustrine sediments: An inter-laboratory comparison

    NARCIS (Netherlands)

    Bahlmann, E.; Bernasconi, S.M.; Bouillon, S.; Houtekamer, M.J.; Korntheuer, M.; Langenberg, F.; Mayr, C.; Metzke, M.; Middelburg, J.J.; Nagel, B.; Struck, U.; Voß, M.; Emeis, K.C.

    2010-01-01

    Nitrogen isotopes of organic matter are increasingly studied in marine biogeochemistry and geology, plant and animal ecology, and paleoceanography. Here, we present results of an inter-laboratory test on determination of nitrogen isotope ratios in marine and lacustrine sediments. Six different

  16. The isotope systematics of a juvenile intraplate volcano: Pb, Nd, and Srisotope ratios of basalts from Loihi Seamount, Hawaii

    International Nuclear Information System (INIS)

    Staudigel, H.; Zindler, A.; Leslie, T.

    1984-01-01

    Sr, Nd, and Pb isotope ratios for a representative suite of 15 basanites, alkali basalts, transitional basalts and tholeiites from Loihi Seamount, Hawaii, display unusually large variations for a single volcano, but lie within known ranges for Hawaiian basalts. Nd isotope ratios in alkali basalts show the largest relative variation (0.51291 - 0.51305), and include the nearly constant tholeiite value (approx.= 0.51297). Pb isotope ratios show similarly large ranges for tholeiites and alkali basalts and continue Tatsumoto's [31] 'Loa' trend towards higher 206 Pb/ 204 Pb, ratios, resulting in a substantial overlap with the 'Kea' trend. 206 Pb/ 204 Pb ratios for Loihi and other volcanoes along the Loa and Kea trends [31] are observed to correlate with the age of the underlying lithosphere suggesting lithosphere involvement in the formation of Hawaiian tholeiites. Loihi lavas display no correlation of Nd, Sr, or Pb isotope ratios with major element compositions or eruptive age, in contrast with observations of some other Hawaiian volcanoes. Isotope data for Loihi, as well as average values for Hawaiian volcanoes, are not adequately explained by previously proposed two-end-member models; new models for the origin and the development of Hawaiian volcanoes must include mixing of at least three geochemically distinct source regions and allow for the involvement of heterogeneous oceanic lithosphere. (orig.)

  17. Lead isotopes in tap water: implications for Pb sources within a municipal water supply system

    International Nuclear Information System (INIS)

    Cheng Zhongqi; Foland, Kenneth A.

    2005-01-01

    Residential tap waters were investigated to examine the feasibility of using isotopic ratios to identify dominant sources of water Pb in the Columbus (Ohio, USA) municipal supply system. Overall, both the concentrations, which are generally low (0.1-28 μg/L), and isotopic compositions of tap water Pb show wide variations. This contrasts with the situation for a limited number of available service lines, which exhibit only a limited Pb-isotope variation but contain Pb of two very different types with one significantly more radiogenic than the other. Most tap water samples in contact with Pb service lines have Pb-isotope ratios that are different from the pipe Pb. Furthermore, the Pb isotope compositions of sequentially drawn samples in the same residence generally are similar, but those from separate residences are different, implying dominant Pb sources from domestic plumbing. A separate pilot study at two residences without Pb service lines shows isotopic similarity between water and solders in each house, further suggesting that the major Pb sources are domestic in these cases and dominated by Pb from solder joints. Although complicated by the broad range of overall Pb-isotope variations observed and limited by sample availability, the results suggest that Pb isotopes can be used effectively to constrain the sources of Pb in tap waters, especially for individual houses where multiple source candidates can be identified

  18. Compound-specific chlorine isotope ratios of TCE, PCE and DCE isomers by direct injection using CF-IRMS

    International Nuclear Information System (INIS)

    Shouakar-Stash, Orfan; Drimmie, Robert J.; Zhang Min; Frape, Shaun K.

    2006-01-01

    A method for determining compound-specific Cl isotopic compositions (δ 37 Cl) was developed for tetrachloroethene (PCE), trichloroethene (TCE), cis-dichloroethene (cis-DCE), trans-dichloroethene (trans-DCE) and 1,1-dichloroethene (1,1-DCE). The isotope ratio mass spectrometry (IRMS) used in this study has nine collectors, including two for m/z 50 and 52 (CH 3 Cl) and two for m/z 94 and 96 (CH 3 Br). The development of this method is based on the fact that fragments with mass ratios of 94/96, 95/97 and 96/98 are produced from PCE, TCE and DCE isomers during ion bombardment in the source of a mass spectrometer. Using continuous flow isotope ratio mass spectrometry coupled with gas chromatography (GC-CF-IRMS), it is possible to separate these compounds on-line and directly measure the Cl isotopic ratios of the fragments with the specific mass ratios. Both pure phase and aqueous samples were used for Cl isotopic analysis. For pure phase samples, a vapour phase of the chlorinated ethenes was injected directly into the GC, whereas the solid phase micro extraction (SPME) method was used to extract these compounds from aqueous solutions. The precisions of this analytical technique were ±0.12 per mille (1σ, n = 30), ±0.06 per mille (1σ, n = 30), and ±0.08 per mille (1σ, n = 15) for PCE, TCE and DCE isomers, respectively. The limits of quantification (LOQ) for analyzing Cl isotopic composition in aqueous solutions were 20, 5, and 5 μg/L for PCE, TCE and DCE isomers, respectively. This corresponds to 6-9 nano-mole of Cl, which is approximately 80 times lower than the most sensitive existing method. Compared to methods previously available, this new development offers the following advantages: (1) The much lower LOQ make it possible to extract these compounds directly from aqueous solutions using SPME without pre-concentration; (2) The linking of a GC with an IRMS eliminates off-line separation; and (3) Because the fragments used for isotopic ratio measurement are

  19. Levels and source apportionment of children's lead exposure: could urinary lead be used to identify the levels and sources of children's lead pollution?

    Science.gov (United States)

    Cao, Suzhen; Duan, Xiaoli; Zhao, Xiuge; Wang, Beibei; Ma, Jin; Fan, Delong; Sun, Chengye; He, Bin; Wei, Fusheng; Jiang, Guibin

    2015-04-01

    As a highly toxic heavy metal, the pollution and exposure risks of lead are of widespread concern for human health. However, the collection of blood samples for use as an indicator of lead pollution is not always feasible in most cohort or longitudinal studies, especially those involving children health. To evaluate the potential use of urinary lead as an indicator of exposure levels and source apportionment, accompanying with environmental media samples, lead concentrations and isotopic measurements (expressed as (207)Pb/(206)Pb, (208)Pb/(206)Pb and (204)Pb/(206)Pb) were investigated and compared between blood and urine from children living in the vicinities of a typical coking plant and lead-acid battery factory. The results showed urinary lead might not be a preferable proxy for estimating blood lead levels. Fortunately, urinary lead isotopic measurements could be used as an alternative for identifying the sources of children's lead exposure, which coincided well with the blood lead isotope ratio analysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Precise isotope ratio and multielement determination in prehistoric and historic human skeletal remains by HR-ICPMS - a novel application to shed light onto anthropological and archaeological questions

    International Nuclear Information System (INIS)

    Watkins, M.

    2000-12-01

    for routine characterization. HR-ICPMS is a widely accepted reliable method for accurate and fast determination of isotope ratios with a precision better than 0.1% RSD. For strontium isotope ratio measurements this precision can be deemed sufficient; since there is enough natural variation in the strontium isotope ratio of the parent rocks, this ratio can be used to characterize and differentiate among local environments. The most important characteristics of isotope ratio measurements by ICPMS are the high sample throughput and comparatively negligible sample preparation prior to measurement, when compared with other techniques. A necessary technical prerequisite is the development of an online matrix separation of 87Rb (as 87Rb leads to an isobaric interference with 87Sr), which is mainly important for analysis of soil samples. This innovative approach will therefore be applied to analyze stable isotope ratios in human skeletal remains (of selected ancient series) but also in soil and rock samples, which should clarify possible diagenetic influences. The necessary sample pretreatment steps, as cleaning digesting and separating enamel from dentin, were established and optimized in order to grant reliable data. Furthermore, suggestive attempts for further research on this topic are presented - based on the critical results obtained from this study. (author)

  1. Precise Isotope ratio and multielement determination in prehistoric and historic human skeletal remains by HR-ICPMS - a novel application to shed light onto anthropological and archaeological questions

    International Nuclear Information System (INIS)

    Watkins, M.

    2000-12-01

    for routine characterization. HR-ICPMS is a widely accepted reliable method for accurate and fast determination of isotope ratios with a precision better than 0.1% RSD. For strontium isotope ratio measurements this precision can be deemed sufficient; since there is enough natural variation in the strontium isotope ratio of the parent rocks, this ratio can be used to characterize and differentiate among local environments. The most important characteristics of isotope ratio measurements by ICPMS are the high sample throughput and comparatively negligible sample preparation prior to measurement, when compared with other techniques. A necessary technical prerequisite is the development of an online matrix separation of 87Rb (as 87Rb leads to an isobaric interference with 87Sr), which is mainly important for analysis of soil samples. This innovative approach will therefore be applied to analyze stable isotope ratios in human skeletal remains (of selected ancient series) but also in soil and rock samples, which should clarify possible diagenetic influences. The necessary sample pretreatment steps, as cleaning digesting and separating enamel from dentin, were established and optimized in order to grant reliable data. Furthermore, suggestive attempts for further research on this topic are presented - based on the critical results obtained from this study. (author)

  2. Ratio of the dose factors of the isotopes of iodine

    International Nuclear Information System (INIS)

    Papadopoulos, D.; Thomas, P.

    1977-12-01

    The ratio of dose factors occurring during inhalation and ingestion to the respective dose factors of I-129 is calculated for the isotopes of I-123 to I-126 and I-129 to I-135. All the dose factors refer to the thyroid as the critical organ. A distinction is made between adults and infants up to 1 year of age. To calculate the ratios only the effective energies and the effective half-lives in the human body and on grass are required. Most of the data have been taken from the literature. The effective energies of I-123 and I-125 have been calculated as examples. (orig.) [de

  3. Dietary heterogeneity among Western industrialized countries reflected in the stable isotope ratios of human hair.

    Science.gov (United States)

    Valenzuela, Luciano O; Chesson, Lesley A; Bowen, Gabriel J; Cerling, Thure E; Ehleringer, James R

    2012-01-01

    Although the globalization of food production is often assumed to result in a homogenization of consumption patterns with a convergence towards a Western style diet, the resources used to make global food products may still be locally produced (glocalization). Stable isotope ratios of human hair can quantify the extent to which residents of industrialized nations have converged on a standardized diet or whether there is persistent heterogeneity and glocalization among countries as a result of different dietary patterns and the use of local food products. Here we report isotopic differences among carbon, nitrogen and sulfur isotope ratios of human hair collected in thirteen Western European countries and in the USA. European hair samples had significantly lower δ(13)C values (-22.7 to -18.3‰), and significantly higher δ(15)N (7.8 to 10.3‰) and δ(34)S (4.8 to 8.3‰) values than samples from the USA (δ(13)C: -21.9 to -15.0‰, δ(15)N: 6.7 to 9.9‰, δ(34)S: -1.2 to 9.9‰). Within Europe, we detected differences in hair δ(13)C and δ(34)S values among countries and covariation of isotope ratios with latitude and longitude. This geographic structuring of isotopic data suggests heterogeneity in the food resources used by citizens of industrialized nations and supports the presence of different dietary patterns within Western Europe despite globalization trends. Here we showed the potential of stable isotope analysis as a population-wide tool for dietary screening, particularly as a complement of dietary surveys, that can provide additional information on assimilated macronutrients and independent verification of data obtained by those self-reporting instruments.

  4. Dietary heterogeneity among Western industrialized countries reflected in the stable isotope ratios of human hair.

    Directory of Open Access Journals (Sweden)

    Luciano O Valenzuela

    Full Text Available Although the globalization of food production is often assumed to result in a homogenization of consumption patterns with a convergence towards a Western style diet, the resources used to make global food products may still be locally produced (glocalization. Stable isotope ratios of human hair can quantify the extent to which residents of industrialized nations have converged on a standardized diet or whether there is persistent heterogeneity and glocalization among countries as a result of different dietary patterns and the use of local food products. Here we report isotopic differences among carbon, nitrogen and sulfur isotope ratios of human hair collected in thirteen Western European countries and in the USA. European hair samples had significantly lower δ(13C values (-22.7 to -18.3‰, and significantly higher δ(15N (7.8 to 10.3‰ and δ(34S (4.8 to 8.3‰ values than samples from the USA (δ(13C: -21.9 to -15.0‰, δ(15N: 6.7 to 9.9‰, δ(34S: -1.2 to 9.9‰. Within Europe, we detected differences in hair δ(13C and δ(34S values among countries and covariation of isotope ratios with latitude and longitude. This geographic structuring of isotopic data suggests heterogeneity in the food resources used by citizens of industrialized nations and supports the presence of different dietary patterns within Western Europe despite globalization trends. Here we showed the potential of stable isotope analysis as a population-wide tool for dietary screening, particularly as a complement of dietary surveys, that can provide additional information on assimilated macronutrients and independent verification of data obtained by those self-reporting instruments.

  5. Effects of must concentration techniques on wine isotopic parameters.

    Science.gov (United States)

    Guyon, Francois; Douet, Christine; Colas, Sebastien; Salagoïty, Marie-Hélène; Medina, Bernard

    2006-12-27

    Despite the robustness of isotopic methods applied in the field of wine control, isotopic values can be slightly influenced by enological practices. For this reason, must concentration technique effects on wine isotopic parameters were studied. The two studied concentration techniques were reverse osmosis (RO) and high-vacuum evaporation (HVE). Samples (must and extracted water) have been collected in various French vineyards. Musts were microfermented at the laboratory, and isotope parameters were determined on the obtained wine. Deuterium and carbon-13 isotope ratios were studied on distilled ethanol by nuclear magnetic resonance (NMR) and isotope ratio mass spectrometry (IRMS), respectively. The oxygen-18 ratio was determined on extracted and wine water using IRMS apparatus. The study showed that the RO technique has a very low effect on isotopic parameters, indicating that this concentration technique does not create any isotopic fractionation, neither at sugar level nor at water level. The effect is notable for must submitted to HVE concentration: water evaporation leads to a modification of the oxygen-18 ratio of the must and, as a consequence, ethanol deuterium concentration is also modified.

  6. Determination of uranium in urine - measurement of isotope ratios and quantification by use of inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Krystek, P.; Ritsema, R.

    2002-01-01

    For analysis of uranium in urine determination of the isotope ratio and quantification were investigated by high-resolution inductively coupled plasma mass spectrometry (HR ICP-MS). The instrument used (ThermoFinniganMAT ELEMENT2) is a single-collector MS and, therefore, a stable sample-introduction system was chosen. The methodical set-up was optimized to achieve the best precision for both the isotope ratio and the total uranium concentration in the urine matrix.Three spiked urine samples from an European interlaboratory comparison were analyzed to determine the 235 U/ 238 U isotope ratio. The ratio was found to be in the range 0.002116 to 0.007222, the latter being the natural uranium isotope ratio. The first ratio indicates the abundance of depleted uranium.The effect of storage conditions and the stability for the matrix urine were investigated by using ''real-life'' urine samples from unexposed persons in the Netherlands. For samples stored under refrigeration and acidified the results (range 0.8 to 5.3 ng L -1 U) were in the normal fluctuation range whereas a decrease in uranium concentration was observed for samples stored at room temperature without acidification. (orig.)

  7. Strontium isotope ratios - a possible tool to study the authenticity of Indian tea using MC-ICP-MS

    International Nuclear Information System (INIS)

    Lagad, Rupali A.; Alamelu, D.; Aggarwal, Suresh K.; Singh, Sunil K.

    2011-01-01

    In the present study, an analytical procedure based on determination of the Sr isotope ratio 87 Sr/ 86 Sr in the Indian tea samples by MC-ICP-MS was developed and applied to 28 tea samples from four different Indian regions. The 87 Sr/ 86 Sr isotope ratio of the tea samples in different Indian regions is strongly dependent on the soil and growth environment condition. The analysis results of 28 Indian tea samples revealed that 87 Sr/ 86 Sr atom ratio follows the order Darjeeling > Kangra > Assam > Munnar

  8. Investigation of groundwater-streamflow interactions in the Bega alluvial aquifer using tritium and stable isotope ratios

    International Nuclear Information System (INIS)

    Stone, D.J.M.; Thomas, M.; Russell, G.

    2001-01-01

    An isotope hydrology study of the Bega Valley groundwater system has been made. The investigation which focussed on environmental tritium and stable isotope ratios confirms that that the groundwater in the alluvial aquifer of the Bega Valley is sustainable at the current usage rate

  9. A comparison of the isotopic composition of lead in rainwater, surface vegetation and tree bark at the long-term monitoring site, Glensaugh, Scotland, in 2007

    Energy Technology Data Exchange (ETDEWEB)

    Farmer, John G., E-mail: J.G.Farmer@ed.ac.uk [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); Eades, Lorna J. [School of Chemistry, University of Edinburgh, Edinburgh EH9 3JJ, Scotland (United Kingdom); Graham, Margaret C.; Cloy, Joanna M. [School of GeoSciences, University of Edinburgh, Edinburgh, EH9 3JN, Scotland (United Kingdom); Bacon, Jeffrey R. [The Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen, AB15 8QH, Scotland (United Kingdom)

    2010-08-01

    The lead concentrations and isotopic ratios ({sup 206}Pb/{sup 207}Pb, {sup 208}Pb/{sup 206}Pb, {sup 208}Pb/{sup 207}Pb) of 31 rainwater (September 2006-December 2007) and 11 surface vegetation (moss, lichen, heather) samples (October 2007) from the rural upland catchment of Glensaugh in northeast Scotland and of nine bark samples (October 2007) from trees, predominantly Scots pine, in or near Glensaugh were determined. The mean {sup 206}Pb/{sup 207}Pb ratios for rainwater in 2006 and 2007 were similar to those previously determined for 2000 to 2003 at Glensaugh, yielding an average mean annual value of 1.151 {+-} 0.005 ({+-} 1 SD) for the period from 2000, when an outright ban on leaded petrol came into force in the UK, to 2007. The mean {sup 206}Pb/{sup 207}Pb ratio (1.146 {+-} 0.004; n = 7) for surface vegetation near the top (430-450 m) of the catchment was not significantly different (Student's t test) from that of rainwater (1.148 {+-} 0.017; n = 24) collected over the 12-month period prior to vegetation sampling, but both were significantly different, at the 0.1% (i.e. p < 0.001) and 1% (p < 0.01) level, respectively, from the corresponding mean value (1.134 {+-} 0.006; n = 9) for the outermost layer of tree bark. When considered in conjunction with similar direct evidence for 2002 and indirect evidence (e.g. grass, atmospheric particulates, dated peat) for recent decades in the Glensaugh area, these findings confirm that the lead isotopic composition of surface vegetation, including that of suitably located moss, reflects that of the atmosphere while that of the outermost layer of Scots pine bark is affected by non-contemporaneous lead. The nature and relative extent of the different contributory sources of lead to the current UK atmosphere in the era of unleaded petrol, however, are presently not well characterised on the basis of lead isotopic measurements.

  10. Isotope ratios and chemical fractionation of CO in Lynds 134

    International Nuclear Information System (INIS)

    Dickman, R.L.; Langer, W.D.

    1977-01-01

    Mahoney, McCutcheon and Shuter (1976) reported observations of the J = 1 → 0 transition of three isotopes of CO in the dust cloud Lynds 134 using the 4.6 m telescope at Aerospace Corporation. In this paper a new observation of 12 C 17 O is discussed and the question of the ratio 13 C 16 O/ 12 C 18 O across the dust cloud is considered further. (Auth.)

  11. Carbon Isotope Measurements of Experimentally-Derived Hydrothermal Mineral-Catalyzed Organic Products by Pyrolysis-Isotope Ratio Mass Spectrometry

    Science.gov (United States)

    Socki, Richard A.; Fu, Qi; Niles, Paul B.

    2011-01-01

    We report results of experiments to measure the C isotope composition of mineral catalyzed organic compounds derived from high temperature and high pressure synthesis. These experiments make use of an innovative pyrolysis technique designed to extract and measure C isotopes. To date, our experiments have focused on the pyrolysis and C isotope ratio measurements of low-molecular weight intermediary hydrocarbons (organic acids and alcohols) and serve as a proof of concept for making C and H isotope measurements on more complicated mixtures of solid-phase hydrocarbons and intermediary products produced during high temperature and high pressure synthesis on mineral-catalyzed surfaces. The impetus for this work stems from recently reported observations of methane detected within the Martian atmosphere [1-4], coupled with evidence showing extensive water-rock interaction during Martian history [5-7]. Methane production on Mars could be the result of synthesis by mineral surface-catalyzed reduction of CO2 and/or CO by Fischer-Tropsch Type (FTT) reactions during serpentization reactions [8,9]. Others have conducted experimental studies to show that FTT reactions are plausible mechanisms for low-molecular weight hydrocarbon formation in hydrothermal systems at mid-ocean ridges [10-12]. Further, recent experiments by Fu et al. [13] focus on examining detailed C isotope measurements of hydrocarbons produced by surface-catalyzed mineral reactions. Work described in this paper details the experimental techniques used to measure intermediary organic reaction products (alcohols and organic acids).

  12. Determination of isotopic ratios of osmium and ruthenium in meteorites by pretreatment and radiochemical neutron activation analysis

    International Nuclear Information System (INIS)

    Chinfang Chai; Yongzhong Liu; Xueying Mao

    1996-01-01

    The isotopic abundance ratios of 190 Os/ 184 Os and 96 Ru/ 102 Ru for the metal phases of the Jilin and Taonan stone meteorites were determined by pretreatment and radiochemical neutron activation analysis. All experimental factors affecting Os and Ru isotopic ratios were discussed, including sampling, standard, irradiation, separation and counting. The statistical errors of measurements for the 199 Os/ 184 Os ratio can be controlled within 1%. The experimental results indicate that the statistically significant anomalies of the 190 Os/ 184 Os and 96 Ru/ 102 Ru ratios have not been found relative to the terrestrial Os and Ru standards. (author). 6 refs., 1 fig., 5 tabs

  13. Novel proxies for reconstructing paleohydrology from ombrotrophic peatlands: biomarker and compound-specific H and C stable isotope ratios

    Science.gov (United States)

    Wang, J.; Nichols, J. E.; Huang, Y.

    2008-12-01

    Ombrotrophic peatlands are excellent archives for paleohydrologic information because they are hydrologically isolated from their surroundings. However, quantitative proxies for deciphering peatland archives are lacking. Here, we present development and application of novel organic geochemical methods for quantitative reconstruction of paleohydrology from the ombrotrophic sediments, and comparison of organic geochemical data with conventional paleoecological proxies. Application of these methods to the sediments of several North American and European peatlands has revealed significant changes in the hydroclimate throughout the Holocene. The plant assemblage living at the surface of the peatland is tightly controlled by surface moisture. Under wet conditions, Sphagnum mosses, with no active mechanism for drawing water from below the surface of the peatland, are dominant. During dry conditions, vascular plants are more productive relative to Sphagnum. A ratio of the abundance of two biomarkers representing Sphagnum and vascular plants sensitively records changes in hydrologic balance (Nichols et al., 2006, Org. Geochem. 37, 1505-1513). We have further developed stable isotope models to compute climate parameters from compound-specific H and C isotope ratios of biomarkers to create a more comprehensive climate reconstruction. Vascular plant leaf waxes carry the D/H ratio signature of precipitation that is little affected by evaporation, whereas the Sphagnum biomarker records isotopic ratios of the water at the peatland surface, which is strongly enriched by evaporation. Evaporation amount can be calculated using the differences between D/H ratios of the two types of biomarkers. C isotope ratios of Sphagnum biomarkers can also be used to quantify surface wetness. Methanotrophic bacteria live symbiotically with Sphagnum, providing isotopically light carbon for photosynthesis. These bacteria are more active when the Sphagnum is wet, thus providing more 13C-depleted CO2

  14. 13CO2/12CO2 ratio analysis in exhaled air by lead-salt tunable diode lasers for noninvasive diagnostics in gastroenterology

    Science.gov (United States)

    Stepanov, Eugene V.; Zyrianov, Pavel V.; Miliaev, Valerii A.; Selivanov, Yurii G.; Chizhevskii, Eugene G.; Os'kina, Svetlana; Ivashkin, Vladimir T.; Nikitina, Elena I.

    1999-07-01

    An analyzer of 13CO2/12CO2 ratio in exhaled air based on lead-salt tunable diode lasers is presented. High accuracy of the carbon isotope ratio detection in exhaled carbon dioxide was achieved with help of very simple optical schematics. It was based on the use of MBE laser diodes operating in pulse mode and on recording the resonance CO2 absorption at 4.2 micrometers . Special fast acquisition electronics and software were applied for spectral data collection and processing. Developed laser system was tested in a clinical train aimed to assessment eradication efficiency in therapy of gastritis associated with Helicobacter pylori infection. Data on the 13C-urea breath test used for P.pylori detection and obtained with tunable diode lasers in the course of the trail was compared with the results of Mass-Spectroscopy analysis and histology observations. The analyzer can be used also for 13CO2/12CO2 ratio detection in exhalation to perform gastroenterology breath test based on using other compounds labeled with stable isotopes.

  15. The determination of initial ratio of strontium isotope in rocks and its geological application

    International Nuclear Information System (INIS)

    Ying Junlong; Zhao Puyun; Lin Xiulan

    1989-04-01

    The method to determine the initial ratio of strontium isotopes existed in rocks of poor rubidium and rich strontium and main carrier minerals is introduced. The initial ratio obtained from this method is equivalent to that acquired by Rb-Sr isochrone. Based on this result, information on regional rock genesis and mineralization regularities can be provided. It has great significance in the research on activities of ancient continental margin and material sources as well as their evolution. The migration of rock, and ore-forming materials, matallogenetic mechanism and its distribution in the space and time evolution are studied by using these data. In conclusion, the determination of strontium isotopes has broad prospects in the geological research

  16. Stable Carbon Isotope Ratio (δ13C Measurement of Graphite Using EA-IRMS System

    Directory of Open Access Journals (Sweden)

    Andrius Garbaras

    2015-06-01

    Full Text Available δ13C values in non-irradiated natural graphite were measured. The measurements were carried out using an elemental analyzer combined with stable isotope ratio mass spectrometer (EA-IRMS. The samples were prepared with ground and non-ground graphite, the part of which was mixed with Mg (ClO42. The best combustion of graphite in the oxidation furnace of the elemental analyzer was achieved when the amount of pulverized graphite ranged from 200 to 490 µg and the mass ratio C:Mg(ClO42 was approximately 1:10. The method for the graphite burning avoiding the isotope fractionation is proposed.DOI: http://dx.doi.org/10.5755/j01.ms.21.2.6873

  17. Laser ablation molecular isotopic spectrometry of water for {sub 1}D{sup 2}/{sub 1}H{sup 1} ratio analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Arnab [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States); Fuel Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Mao, Xianglei; Chan, George C.-Y. [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States); Russo, Richard E., E-mail: rerusso@lbl.gov [Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720 (United States)

    2013-10-01

    Laser Ablation Molecular Isotopic Spectrometry (LAMIS) has been investigated for optical isotopic analysis of the deuterium to protium ratio in enriched water samples in ambient air at atmospheric pressure. Multivariate PLSR (Partial Least Squares Regression) based calibrations were carried out and validated using multiple statistical parameters. Comparisons of results are reported using two spectrometers having two orders of magnitude difference in spectral resolution. The accuracy and precision of isotopic analysis depends on the spectral resolution and the inherent isotope shift of the elements. The requirements for spectral resolution of the measurement system can be significantly relaxed when the isotopic abundance ratio is determined using chemometric processing of the spectra. Large isotopic shifts in the individual rotational branches of OH/OD molecular emission spectra were measured. Optimized temporal conditions for LAMIS measurements were established. Several sub-regions of spectra were used for PLSR calibration and the results demonstrate that both the emission intensity and degree of spectral differentiation affect the quality of the PLSR calibration. LAMIS results also were compared with traditional LIBS results obtained using PLSR and a spectral deconvolution method, demonstrating the advantages of LAMIS over LIBS with respect to isotopic composition determination. - Highlights: • D/H isotopic ratio in water over a large dynamic range was measured by LAMIS. • PLSR based multivariate calibration was used for construction of calibrations. • Region of interest significantly affects the analytical results of isotopic ratio. • LAMIS has improved results over LIBS irrespective of the spectrometer resolution. • The superiority is more prominent in the case using low resolution spectrometer.

  18. On the source material of magmas - with special reference to Nd isotopic ratios of igneous rocks

    International Nuclear Information System (INIS)

    Shuto, Kenji

    1980-01-01

    In 1973, the Sm-Nd method was first used for the measurement of the absolute age of igneous rocks and meteorites. Subsequently in the following years, the research works by means of the Nd isotopic ratio in igneous rocks have been made strenuously in order to reveal the chemistry of the source materials of magma giving rise to the igneous rocks and further the evolution process of mantle and earth's crust. The fundamental items for the Sm-Nd method are explained. Then, the research results more important in the above connection are given. Finally, the ideas by the author concerning the source materials of magma are presented from the data available on the Nd isotopes in meteorites and igneous rocks. The following matters are described: the fundamentals of Sm-Nd method, the Nd content in seawater, the negative correlation between Nd and Sr isotopic ratios in igneous rocks, magma source materials and Nd isotopes, and considerations on magma source materials. (J.P.N.)

  19. Online Stable Isotope Analysis of Dissolved Organic Carbon Size Classes Using Size Exclusion Chromatography Coupled to an Isotope Ratio Mass Spectrometer

    Digital Repository Service at National Institute of Oceanography (India)

    Malik, A.; Scheibe, A.; LokaBharathi, P.A.; Gleixner, G.

    size classes by coupling high-performance liquid chromatography (HPLC) - size exclusion chromatography (SEC) to online isotope ratio mass spectrometry (IRMS). This represents a significant methodological contribution to DOC research. The interface...

  20. Lead contamination and transfer in urban environmental compartments analyzed by lead levels and isotopic compositions.

    Science.gov (United States)

    Hu, Xin; Sun, Yuanyuan; Ding, Zhuhong; Zhang, Yun; Wu, Jichun; Lian, Hongzhen; Wang, Tijian

    2014-04-01

    Lead levels and isotopic compositions in atmospheric particles (TSP and PM2.5), street dust and surface soil collected from Nanjing, a mega city in China, were analyzed to investigate the contamination and the transfer of lead in urban environmental compartments. The lead contents in TSP and PM2.5 are significantly higher than them in the surface soil and street dust (p lead to the major crustal elements (Al, Sr, Ti and Fe) indicates significant lead enrichment in atmospheric particles. The plots of (206)Pb/(207)Pb vs.(208)Pb/(206)Pb and (206)Pb/(207)Pb vs. 1/Pb imply that the street dust and atmospheric particles (TSP and PM2.5) have very similar lead sources. Coal emissions and smelting activities may be the important lead sources for street dust and atmospheric particles (TSP and PM2.5), while the deposition of airborne lead is an important lead source for urban surface soil. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Nitrogen-isotope ratios of nitrate in ground water under fertilized fields, Long Island, New York

    Science.gov (United States)

    Flipse, W.J.; Bonner, F.T.

    1985-01-01

    Ground-water samples from two heavily fertilized sites in Suffolk County, New York, were collected through the 1978 growing season and analyzed for nitrate-N concentrations and nitrogen-isotope ratios. Six wells were at a potato farm; six were on a golf course. The purpose of this study was to determine whether the 15N/14N ratios (??15N values) of fertilizer are increased during transit from land surface to ground water to an extent which would preclude use of this ratio to distinguish agricultural from animal sources of nitrate in ground water. Ground water at both sites contained a greater proportion of 15N than the fertilizers being applied. At the potato farm, the average ??15N value of the fertilizers was 0.2???; the average ??15N value of the ground-water nitrate was 6.2???. At the golf course, the average ??15N value of the fertilizers was -5.9???, and that of ground-water nitrate was 6.5???. The higher ??15N values of ground-water nitrate are probably caused by isotopic fractionation during the volatile loss of ammonia from nitrogen applied in reduced forms (NH4+ and organic-N). The ??15N values of most ground-water samples from both areas were less than 10???, the upper limit of the range characteristic of agricultural sources of nitrate; these sources include both fertilizer nitrate and nitrate derived from increased mineralization of soil nitrogen through cultivation. Previous studies have shown that the ??15N values of nitrate derived from human or animal waste generally exceed 10???. The nitrogen-isotope ratios of fertilizer-derived nitrate were not altered to an extent that would make them indistinguishable from animal-waste-derived nitrates in ground water.Ground-water samples from two heavily fertilized sites in Suffolk County, New York, were collected through the 1978 growing season and analyzed for nitrate-N concentrations and nitrogen-isotope ratios. Six wells were at a potato farm; six were on a golf course. The purpose of this study was to

  2. Geographical variations in Sr and Nd isotopic ratios of cryoconite on Asian glaciers

    International Nuclear Information System (INIS)

    Nagatsuka, Naoko; Takeuchi, Nozomu; Nakano, Takanori; Shin, Kicheol; Kokado, Emi

    2014-01-01

    Cryoconite is a dark-coloured surface dust deposited on glaciers that consists of wind-blown mineral particles, as well as organic matter derived from microbes living on glaciers. In this paper, we analyse the Sr and Nd isotopic ratios of four mineral fractions (i.e., the saline, carbonate, phosphate, and silicate mineral fractions), as well as the organic fraction, of cryoconite samples obtained from six Asian glaciers (the Altai, Pamir, Tien Shan, Qillian Shan, and Himalayan regions), and discuss their geographical variations in terms of the geological origins of the mineral particles and the biogeochemical processes on the glaciers. The silicate mineral fraction showed lower Sr and higher Nd ratios for the glaciers located to the north (Altai, 87 Sr/ 86 Sr: 0.713 490–0.715 284, εNd(0): −6.4 to −5.6), while higher Sr and lower Nd ratios for the glaciers located to the south (Himalayas, 87 Sr/ 86 Sr: 0.740 121–0.742 088, εNd(0): −16.4 to −15.7); the ratios were similar to those of desert sand, loess, and river sediments in the respective regions of the glaciers. This result suggests that the silicate minerals within the cryoconites were derived from different sources depending on the geographical locations of the glaciers. The isotopic ratios of the saline, carbonate, and phosphate mineral fractions were distinct from those of the silicate fraction, and were similar to those of evaporites and apatite deposits from the Asian deserts, but also varied geographically, indicating that they are likely to reflect their geological origin. The Sr isotopic ratios of the organic fraction were similar to those of the saline and carbonate fractions from glaciers in the central area (Tien Shan and Qillian Shan), but were higher than those of the saline and carbonate fractions, and lower than the phosphate mineral fraction, in the northern and southern areas. The ratios of organic fraction may be determined from the mixing ratio of calcium sources

  3. Traceability of different apple varieties by multivariate analysis of isotope ratio mass spectrometry data.

    Science.gov (United States)

    Mimmo, Tanja; Camin, Federica; Bontempo, Luana; Capici, Calogero; Tagliavini, Massimo; Cesco, Stefano; Scampicchio, Matteo

    2015-11-15

    The awareness of customers of the origin of foods has become an important issue. The growing demand for foods that are healthy, safe and of high quality has increased the need for traceability and clear labelling. Thus, this study investigates the capability of C and N stable isotope ratios to determine the geographical origin of several apple varieties grown in northern Italy. Four apple varieties (Cripps Pink, Gala, Golden Delicious, Granny Smith) have been sampled in orchards located in the Districts of Bolzano, Ferrara, Verona and Udine (northern Italy). Carbon (δ(13) C) and nitrogen (δ(15) N) isotope values of the whole apple fruits and three sub-fractions (peel, pulp and seed) have been determined simultaneously by isotope ratio mass spectrometry. The δ(13) C and δ(15) N values of apples and apple sub-fractions, such as peel, seed and pulp, were significantly affected by the geographical origin and the fruit variety. The four varieties could be distinguished to a certain extent only within each district. A 99% correct identification of the samples according to their origin was, however, achieved by cross validation with the 'leave-one-out' method. This study proves the potential of stable isotopes to discriminate the geographical origin of apples grown in orchards located only a few hundreds of kilometres apart. Stable isotopes were also able to discriminate different apple varieties, although only within small geographical areas. Copyright © 2015 John Wiley & Sons, Ltd.

  4. Central depression of the charge density distributions in lead isotopes

    International Nuclear Information System (INIS)

    Haddad, S.

    2008-01-01

    The central-depression parameters is determined by fitting the charge density distributions in lead isotopes to a three-parameter Fermi distribution. The central-depression parameter increases with the number of neutrons due to the isovector coupling channel of the nuclear interaction and its dependency on density. (author)

  5. Central depression of the charge density distributions in lead isotopes

    International Nuclear Information System (INIS)

    Haddad, S.

    2007-01-01

    The central-depression parameter is determined by fitting the charge density distributions in lead isotopes to a three-parameter Fermi distribution. The central-depression parameter increases with the number of neutrons due to the isovector coupling channel of the nuclear interaction and its dependency on density. (author)

  6. Determination of 240Pu/239Pu isotope ratios in Kara Sea and Novaya Zemlya sediments using accelerator mass spectrometry

    International Nuclear Information System (INIS)

    Oughton, D.H.; Skipperud, L.; Salbu, B.; Fifield, L.K.; Cresswell, R.C.; Day, J.P.

    1999-01-01

    Accelerator mass spectrometry (AMS) has been used to determine Pu activity concentrations and 240 Pu/ 239 Pu isotope ratios in sediments from the Kara Sea and radioactive waste dumping sites at Novaya Zemlya. Measured 239,240 Pu activities ranged from 0.06 - 9.8 Bq/kg dry weight, 240 Pu/ 239 Pu atom ratios ranged from 0.13 to 0.28, and 238 Pu/ 239,240 Pu activity ratios from 0.02 to 0.6. Perturbations from global fallout isotope ratios were evident at three sites: the Yenisey Estuary and Abrosimov Fjords where 240 Pu/ 239 Pu ratios were lower (0.13-0.14); and Stepovogo Fjord sediments where ratios were higher (up to 0.28) than fallout ratios. Based on procedural blanks, detection limits for AMS were below 1 fg Pu and the method showed good precision for isotope ratio measurements, minimal matrix, interference and memory effects. For high level samples, comparison between alpha spectrometry and AMS gave good agreement for measurement of 239,240 Pu activity concentrations. (author)

  7. The lead (Pb) isotope signature, behaviour and fate of traffic-related lead pollution in roadside soils in The Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Walraven, N., E-mail: n.walraven@geoconnect.nl [GeoConnect, Meester Dekkerstraat 4, 1901 PV Castricum (Netherlands); Os, B.J.H. van, E-mail: b.vanos@rce.nl [Rijksdienst voor Archeologie, Cultuurlandschap en Monumenten, P.O. Box 1600, 3800 BP Amersfoort (Netherlands); Klaver, G.Th., E-mail: g.klaver@brgm.nl [BRGM, 3 avenue Claude-Guillemin, BP 36009, 45060 Orléans Cedex 2 (France); Middelburg, J.J., E-mail: j.b.m.middelburg@uu.nl [University Utrecht, Faculty of Geosciences, P.O. Box 80021, 3508 TA Utrecht (Netherlands); Davies, G.R., E-mail: g.r.davies@vu.nl [VU University Amsterdam, Faculty of Earth and Life Sciences, Petrology, De Boelelaan 1085, 1081 HV Amsterdam (Netherlands)

    2014-02-01

    In this study the origin, behaviour and fate of anthropogenic Pb in sandy roadside soils were assessed by measuring soil characteristics, Pb isotope composition and content. In 1991 and 2003 samples were taken at different depth intervals at approximately 8 and 75 m from two highways in The Netherlands. The Pb isotope composition of the litter layer ({sup 206}Pb/{sup 207}Pb = 1.12–1.14) differs from the deeper soil samples ({sup 206}Pb/{sup 207}Pb = 1.20–1.21). Based on a mixing model it is concluded that the samples contain two Pb sources: natural Pb and anthropogenic Pb, the latter mainly derived from gasoline. {sup 206}Pb/{sup 207}Pb ratios demonstrate that the roadside soils were polluted to a depth of ∼ 15 cm. Within this depth interval, anthropogenic Pb content is associated with organic matter. Although Pb pollution only reached a depth of ∼ 15 cm, this does not mean that the topsoils retain all anthropogenic Pb. Due to the low pH and negligible binding capacity of soils at depths > 15 cm, anthropogenic Pb migrated towards groundwater after reaching depths of > 15 cm. The Pb isotope composition of the groundwater ({sup 206}Pb/{sup 207}Pb = 1.135–1.185) establishes that groundwater is polluted with anthropogenic Pb. The contribution of anthropogenic Pb to the groundwater varies between ∼ 30 and 100%. Based on the difference in soil Pb content and Pb isotope compositions over a period of 12 years, downward Pb migration is calculated to vary from 72 ± 95 to 324 ± 279 mg m{sup −2} y{sup −1}. Assuming that the downward Pb flux is constant over time, it is calculated that 35–90% of the atmospherically delivered Pb has migrated to the groundwater. - Highlights: • Lead isotope composition of litter and topsoil differs from the deeper soil samples. • Litter and topsoil contain anthropogenic Pb, with gasoline Pb as main source. • Anthropogenic Pb is strongly associated with organic matter in litter and topsoil. • Approximately 35–90% of

  8. Caution on the use of liquid nitrogen traps in stable hydrogen isotope-ratio mass spectrometry

    Science.gov (United States)

    Coplen, Tyler B.; Qi, Haiping

    2010-01-01

    An anomalous stable hydrogen isotopic fractionation of 4 ‰ in gaseous hydrogen has been correlated with the process of adding liquid nitrogen (LN2) to top off the dewar of a stainless-steel water trap on a gaseous hydrogen-water platinum equilibration system. Although the cause of this isotopic fractionation is unknown, its effect can be mitigated by (1) increasing the capacity of any dewars so that they do not need to be filled during a daily analytic run, (2) interspersing isotopic reference waters among unknowns, and (3) applying a linear drift correction and linear normalization to isotopic results with a program such as Laboratory Information Management System (LIMS) for Light Stable Isotopes. With adoption of the above guidelines, measurement uncertainty can be substantially improved. For example, the long-term (months to years) δ2H reproducibility (1& sigma; standard deviation) of nine local isotopic reference waters analyzed daily improved substantially from about 1‰ to 0.58 ‰. This isotopically fractionating mechanism might affect other isotope-ratio mass spectrometers in which LN2 is used as a moisture trap for gaseous hydrogen

  9. The distribution of lead concentrations and isotope compositions in the eastern Tropical Atlantic Ocean

    Science.gov (United States)

    Bridgestock, Luke; Rehkämper, Mark; van de Flierdt, Tina; Paul, Maxence; Milne, Angela; Lohan, Maeve C.; Achterberg, Eric P.

    2018-03-01

    Anthropogenic emissions have dominated marine Pb sources during the past century. Here we present Pb concentrations and isotope compositions for ocean depth profiles collected in the eastern Tropical Atlantic Ocean (GEOTRACES section GA06), to trace the transfer of anthropogenic Pb into the ocean interior. Variations in Pb concentration and isotope composition were associated with changes in hydrography. Water masses ventilated in the southern hemisphere generally featured lower 206Pb/207Pb and 208Pb/207Pb ratios than those ventilated in the northern hemisphere, in accordance with Pb isotope data of historic anthropogenic Pb emissions. The distributions of Pb concentrations and isotope compositions in northern sourced waters were consistent with differences in their ventilation timescales. For example, a Pb concentration maximum at intermediate depth (600-900 m, 35 pmol kg-1) in waters sourced from the Irminger/Labrador Seas, is associated with Pb isotope compositions (206Pb/207Pb = 1.1818-1.1824, 208Pb/207Pb = 2.4472-2.4483) indicative of northern hemispheric emissions during the 1950s and 1960s close to peak leaded petrol usage, and a transit time of ∼50-60 years. In contrast, North Atlantic Deep Water (2000-4000 m water depth) featured lower Pb concentrations and isotope compositions (206Pb/207Pb = 1.1762-1.184, 208Pb/207Pb = 2.4482-2.4545) indicative of northern hemispheric emissions during the 1910s and 1930s and a transit time of ∼80-100 years. This supports the notion that transient anthropogenic Pb inputs are predominantly transferred into the ocean interior by water mass transport. However, the interpretation of Pb concentration and isotope composition distributions in terms of ventilation timescales and pathways is complicated by (1) the chemical reactivity of Pb in the ocean, and (2) mixing of waters ventilated during different time periods. The complex effects of water mass mixing on Pb distributions is particularly apparent in seawater in the

  10. Analytical techniques for determination of framework oxygen isotope ratio of wairakite

    International Nuclear Information System (INIS)

    Noto, Masami; Kusakabe, Minoru; Uchida, Tetsuo.

    1990-01-01

    Dehydration techniques were developed for the analysis of isotopic ratios of framework oxygen of wairakite, one of calcium zeolites often encountered in geothermal systems. Channel water in wairakite were separated from aluminosilicate framework by dehydration in vacuum at 300 deg, 400 deg, 450 deg, 500 deg, 550 deg, 650 deg, 750 deg, 850 deg, and 950 degC, and by stepwise heating at temperatures from 300 deg to 700 degC. The oxygen isotopic analyses of the separated channel water and the residual aluminosilicate framework of wairakite indicated that dehydration at temperatures higher than 400 degC is accompanied by isotopic exchang between the framework oxygen and dehydrating water vapor. The isotopic exchange during the high temperature dehydration makes the δ 18 O of framework oxygen lower and that of channel water higher than those obtained by dehydration at 300 degC. These results are consistent with dehydration behavior of wairakite under vacuum that the maximum rate of dehydration of channel water is attained at about 400 degC. Consequently it is recommended to dehydrate wairakite at a temperature as low as possible in order to avoid the effect of the isotopic exchange. Time required to attain complete dehydration becomes longer with lowering the temperature of dehydration. To compromise these conflicting effects, the optimum conditions of dehydration have been found that most of the channel water is dehydrated at 300 degC for 24 hours, followed by stepwise heating for additional 17 hours up to 700 degC. We obtained a better than ± 0.1 reproducibility for the framework oxygen isotopic determinations with this technique. (author)

  11. Measurements of stable isotope ratios in milk samples from a farm placed in the mountains of Transylvania

    Energy Technology Data Exchange (ETDEWEB)

    Magdas, D. A., E-mail: gabriela.cristea@itim-cj.ro; Cristea, G., E-mail: gabriela.cristea@itim-cj.ro; Bot, A.; Puscas, R.; Radu, S.; Mirel, V. [National Institute for Research and Development of Isotopic and Molecular Technologies, 65-103 Donath Str., 400293 Cluj-Napoca (Romania); Cordea, D. V.; Mihaiu, M. [University of Agricultural Science and Veterinary Medicine, 3-5 Calea Manastur, 400372 Cluj-Napoca (Romania)

    2013-11-13

    Product origin is of great importance for consumers especially because its association in consumer's perception with food quality, freedom from disease or pollution. Stable isotope ratio analysis is a powerful technique in food authenticity and traceability control which has been introduced within the European wine industry to ensure authenticity of wine provenance and to detect adulteration. Isotopic ratios measurements have also been successfully to other food commodities like: fruit juices, honey and dairy foods. The δ{sup 18}O and δ{sup 2}H content in milk water reflects the isotope composition of the ground water drunk by animals. Seasonal effects are also very important: in summer, milk water contains higher δ{sup 18}O and δ{sup 2}H values due to the fresh plants that are ate by animals. Relative carbon stable isotope abundances in total milk reflect the isotopic composition of the diet fed to the dairy cows. In this study the hydrogen, oxygen and carbon isotopic composition of 15 milk samples coming from a unit placed in the mountains of Transylvania was investigated. The distribution of the obtained isotopic values was than discussed taking into account that all the animals were feed with the same type of forage and consumed water was taken from the same source.

  12. Measurements of stable isotope ratios in milk samples from a farm placed in the mountains of Transylvania

    International Nuclear Information System (INIS)

    Magdas, D. A.; Cristea, G.; Bot, A.; Puscas, R.; Radu, S.; Mirel, V.; Cordea, D. V.; Mihaiu, M.

    2013-01-01

    Product origin is of great importance for consumers especially because its association in consumer's perception with food quality, freedom from disease or pollution. Stable isotope ratio analysis is a powerful technique in food authenticity and traceability control which has been introduced within the European wine industry to ensure authenticity of wine provenance and to detect adulteration. Isotopic ratios measurements have also been successfully to other food commodities like: fruit juices, honey and dairy foods. The δ 18 O and δ 2 H content in milk water reflects the isotope composition of the ground water drunk by animals. Seasonal effects are also very important: in summer, milk water contains higher δ 18 O and δ 2 H values due to the fresh plants that are ate by animals. Relative carbon stable isotope abundances in total milk reflect the isotopic composition of the diet fed to the dairy cows. In this study the hydrogen, oxygen and carbon isotopic composition of 15 milk samples coming from a unit placed in the mountains of Transylvania was investigated. The distribution of the obtained isotopic values was than discussed taking into account that all the animals were feed with the same type of forage and consumed water was taken from the same source

  13. Validation of a dual-isotope plasma ratio method for measurement of cholesterol absorption in rats

    International Nuclear Information System (INIS)

    Zilversmit, D.B.; Hughes, L.B.

    1974-01-01

    Several methods for measuring cholesterol absorption in the rat have been compared. After administration of an oral dose of labeled cholesterol ( 14 C or 3 H) and an intravenous dose of colloidal labeled cholesterol ( 3 H or 14 C) the ratio of the two labels in plasma or whole blood 48 hr or more after dosing compared closely to the ratio of areas under the respective specific activity-time curves. The area ratio method is independent of a time lag between the appearance of oral and intravenous label in the bloodstream. Both measures of cholesterol absorption agree fairly well with a method based on measuring the unabsorbed dietary cholesterol in a pooled fecal sample. The plasma isotope ratio method gave more reproducible results than the fecal collection method when the measurement was repeated in the same animals 5 days after the first measurement. Cholesterol absorption was overestimated by the use of Tween 20-solubilized labeled cholesterol for the intravenous dose. The plasma disappearance curves of injected labeled colloidal cholesterol and cholesterol-labeled chylomicrons infused intravenously over a 3.5-h period in the same animal coincided within experimental error from the first day until 75 days after injection. The plasma isotope ratio method for cholesterol absorption gave the same results in rats practicing coprophagy as in those in which this practice was prevented. The addition of sulfaguanidine to the diet lowered cholesterol absorption as measured by the plasma isotope ratio to the same degree as that measured by the fecal collection method. (U.S.)

  14. Delayed visual maturation is not from lead pollution

    International Nuclear Information System (INIS)

    Gulson, B.L.; Howarth, D.

    2000-01-01

    radioactive decay, the amounts (abundances) have changed over geological time and this is reflected in the geological source of the lead. The abundances are usually expressed as ratios. Lead from the geologically old (∼1700 million years old) lead-zinc-silver deposits of Broken Hill in NSW has an 206 Pb/ 204 Pb abundance ratio of 16.00 whereas the ratio is 18.1-18.3 for geologically young deposits, 500-400 million years old, on the same continent or from the northern hemisphere. It is these isotopic differences that are used to evaluate the source of lead in the environment, humans and animals. Interpretations of lead isotopic data may not be straightforward because lead in the environment or animals may be a mixture of lead from different sources (mines). Hence, lead that is introduced to the body from air/food/water is largely dependent on the source of lead in the environment, which in turn is dependent on the age and hence isotopic composition of the rocks/ores from which the lead in the environment is derived

  15. Stable carbon isotope ratio profiling of illicit testosterone preparations--domestic and international seizures.

    Science.gov (United States)

    Brooker, Lance; Cawley, Adam; Drury, Jason; Edey, Claire; Hasick, Nicole; Goebel, Catrin

    2014-10-01

    Gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) is now established as a robust and mature analytical technique for the doping control of endogenous anabolic androgenic steroids in human sport. It relies on the assumption that the carbon isotope ratios of naturally produced steroids are significantly different to synthetically manufactured testosterone or testosterone prohormones used in commercial medical or dietary supplement products. Recent publications in this journal have highlighted the existence of black market testosterone preparations with carbon isotope ratios within the range reported for endogenous steroids (i.e. δ(13) C ≥ -25.8 ‰). In this study, we set out to profile domestic and international law enforcement seizures of illicit testosterone products to monitor the prevalence of 'enriched' substrates--which if administered to human subjects would be considered problematic for the use of current GC-C-IRMS methodologies for the doping control of testosterone in sport. The distribution of δ(13) C values for this illicit testosterone sample population (n = 283) ranged from -23.4 ‰ to -32.9 ‰ with mean and median of -28.6 ‰--comparable to previous work. However, only 13 out of 283 testosterone samples (4.6 %) were found to display δ(13) C values ≥ -25.8 ‰, confirming that in the vast majority of cases of illicit testosterone administration, current GC-C-IRMS doping control procedures would be capable of confirming misuse. Copyright © 2014 John Wiley & Sons, Ltd.

  16. Identification of Marchfeld asparagus using Sr isotope ratio measurements by MC-ICP-MS.

    Science.gov (United States)

    Swoboda, S; Brunner, M; Boulyga, S F; Galler, P; Horacek, M; Prohaska, T

    2008-01-01

    This work focuses on testing and application of Sr isotope signatures for the fast and reliable authentication and traceability of Asparagus officinalis originating from Marchfeld, Austria, using multicollector inductively coupled plasma mass spectrometry after optimised Rb/Sr separation. The major sample pool comprises freeze-dried and microwave-digested asparagus samples from Hungary and Slovakia which are compared with Austrian asparagus originating from the Marchfeld region, which is a protected geographical indication. Additional samples from Peru, The Netherlands and Germany were limited in number and allowed therefore only restricted statistical evaluation. Asparagus samples from Marchfeld were harvested within two subsequent years in order to investigate the annual variation. The results show that the Sr isotope ratio is consistent within these 2 years of investigation. Moreover, the Sr isotope ratio of total Sr in soil was found to be significantly higher than in an NH4NO3 extract, reflecting the mobile (bioavailable) phase. The isotope composition in the latter extract corresponds well to the range found in the asparagus samples in Marchfeld, even though the concentration of Sr in asparagus shows no direct correlation to the concentration of Sr in the mobile phase of the soil. The major question was whether the 'Marchfelder Spargel' can be distinguished from samples from the neighbouring countries of Hungary and Slovakia. According to our findings, they can be clearly (100%) singled out from the Hungarian samples and can be distinguished from the Slovakian asparagus samples with a probability of more than 80%.

  17. Field Sample Preparation Method Development for Isotope Ratio Mass Spectrometry

    International Nuclear Information System (INIS)

    Leibman, C.; Weisbrod, K.; Yoshida, T.

    2015-01-01

    Non-proliferation and International Security (NA-241) established a working group of researchers from Los Alamos National Laboratory (LANL), Pacific Northwest National Laboratory (PNNL) and Savannah River National Laboratory (SRNL) to evaluate the utilization of in-field mass spectrometry for safeguards applications. The survey of commercial off-the-shelf (COTS) mass spectrometers (MS) revealed no instrumentation existed capable of meeting all the potential safeguards requirements for performance, portability, and ease of use. Additionally, fieldable instruments are unlikely to meet the International Target Values (ITVs) for accuracy and precision for isotope ratio measurements achieved with laboratory methods. The major gaps identified for in-field actinide isotope ratio analysis were in the areas of: 1. sample preparation and/or sample introduction, 2. size reduction of mass analyzers and ionization sources, 3. system automation, and 4. decreased system cost. Development work in 2 through 4, numerated above continues, in the private and public sector. LANL is focusing on developing sample preparation/sample introduction methods for use with the different sample types anticipated for safeguard applications. Addressing sample handling and sample preparation methods for MS analysis will enable use of new MS instrumentation as it becomes commercially available. As one example, we have developed a rapid, sample preparation method for dissolution of uranium and plutonium oxides using ammonium bifluoride (ABF). ABF is a significantly safer and faster alternative to digestion with boiling combinations of highly concentrated mineral acids. Actinides digested with ABF yield fluorides, which can then be analyzed directly or chemically converted and separated using established column chromatography techniques as needed prior to isotope analysis. The reagent volumes and the sample processing steps associated with ABF sample digestion lend themselves to automation and field

  18. Mixed-mode chromatography/isotope ratio mass spectrometry.

    Science.gov (United States)

    McCullagh, James S O

    2010-03-15

    Liquid chromatography coupled to molecular mass spectrometry (LC/MS) has been a standard technique since the early 1970s but liquid chromatography coupled to high-precision isotope ratio mass spectrometry (LC/IRMS) has only been available commercially since 2004. This development has, for the first time, enabled natural abundance and low enrichment delta(13)C measurements to be applied to individual analytes in aqueous mixtures creating new opportunities for IRMS applications, particularly for the isotopic study of biological molecules. A growing number of applications have been published in a range of areas including amino acid metabolism, carbohydrates studies, quantification of cellular and plasma metabolites, dietary tracer and nucleic acid studies. There is strong potential to extend these to new compounds and complex matrices but several challenges face the development of LC/IRMS methods. To achieve accurate isotopic measurements, HPLC separations must provide baseline-resolution between analyte peaks; however, the design of current liquid interfaces places severe restrictions on compatible flow rates and in particular mobile phase compositions. These create a significant challenge on which reports associated with LC/IRMS have not previously focused. Accordingly, this paper will address aspects of chromatography in the context of LC/IRMS, in particular focusing on mixed-mode separations and their benefits in light of these restrictions. It aims to provide an overview of mixed-mode stationary phases and of ways to improve high aqueous separations through manipulation of parameters such as column length, temperature and mobile phase pH. The results of several practical experiments are given using proteogenic amino acids and nucleosides both of which are of noted importance in the LC/IRMS literature. This communication aims to demonstrate that mixed-mode stationary phases provide a flexible approach given the constraints of LC/IRMS interface design and acts as a

  19. Production of He-, Ne-, Ar-, Kr-, and Xe-isotopes by proton-induced reactions on lead

    International Nuclear Information System (INIS)

    Leya, I.; Michel, R.

    2003-01-01

    We measured integral thin target cross sections for the proton-induced production of He-, Ne-, Ar-, Kr-, and Xe-isotopes from lead from the respective reaction thresholds up to 2.6 GeV. The production of noble gas isotopes in lead by proton-induced reactions is of special importance for design studies of accelerator driven systems and energy amplifiers. In order to minimise the influences of secondary particles on the production of residual nuclides a new Mini-Stack approach was used instead of the well-known stacked-foil techniques for all experiments with proton energies above 200 MeV. With some exceptions our database for the proton-induced production of noble gas isotopes from lead is consistent and nearly complete. In contradistinction to the production of He from Al and Fe, where the cross sections obtained by thin-target irradiation experiments are up to a factor of 2 higher than the NESSI data, both datasets agree for the He production from lead. (orig.)

  20. Stable carbon isotopic composition of gasolines determined by isotope ratio monitoring gas chromatography mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Smallwood, B.J.; Philp, R.P.; Allen, J.D. [University of Oklahoma, Norman, OK (United States). School of Geology and Geophysics

    2002-07-01

    A large number of underground gasoline storage facilities in the United States continuously leak gasoline into the subsurface, which makes gasoline a major groundwater contaminant. Gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) are used currently to characterize contaminated groundwater and soils. Correlations of contaminants with suspected source(s) are extremely difficult by these techniques because many gasolines have similar hydrocarbon distributions. The present study applied the technique of isotope ratio monitoring gas chromatography-mass spectrometry (irmGC-MS) to 19 gasoline samples from different areas of the USA. This allows a much better correlation of gasoline contaminants to source. Data obtained indicate a wide range of {sup {delta}}{sup 13}C values for 16 ubiquitous compounds in the gasolines. The majority of samples could be distinguished from each other on the basis of {sup {delta}}{sup 13}C hydrocarbon composition. The oxygenated additive methyl tertiary butyl ether (MTBE) was present in ten of the gasolines analyzed, and had a relatively narrow range of {sup {delta}}{sup 13}C values (-30.4 to -28.3 per mille). Preliminary investigations were also made to determine the extent of carbon isotopic fractionation after simple water washing and evaporation experiments. Results indicate that the majority of compounds did not undergo significant carbon isotopic fractionation as a result of these processes. (author)

  1. Genetic interpretation of lead-isotopic data from the Columbia River basalt group, Oregon, Washington, and Idaho.

    Science.gov (United States)

    Church, S.E.

    1985-01-01

    Lead-isotopic data for the high-alumina olivine plateau basalts and most of the Colombia River basalt group plot within the Cascade Range mixing array. The data for several of the formations form small, tight clusters and the Nd and Sr isotopic data show discrete variation between these basalt groups. The observed isotopic and trace-element data from most of the Columbia River basalt group can be accounted for by a model which calls for partial melting of the convecting oceanic-type mantle and contamination by fluids derived from continental sediments which were subducted along the trench. These sediments were transported in the low-velocity zone at least 400 km behind the active arc into a back-arc environment represented by the Columbia Plateau province. With time, the zone of melting moved up, resulting in the formation of the Saddle Mt basalt by partial melting of a 2600 m.y.-old sub-continental lithosphere characterized by high Th/U, Th/Pb, Rb/Sr and Nd/Sm ratios and LREE enrichment. Partial melting of old sub-continental lithosphere beneath the continental crust may be an important process in the formation of continental tholeiite flood basalt sequences world-wide. -L.di H.

  2. Enhanced forensic discrimination of pollutants by position-specific isotope analysis using isotope ratio monitoring by (13)C nuclear magnetic resonance spectrometry.

    Science.gov (United States)

    Julien, Maxime; Nun, Pierrick; Höhener, Patrick; Parinet, Julien; Robins, Richard J; Remaud, Gérald S

    2016-01-15

    In forensic environmental investigations the main issue concerns the inference of the original source of the pollutant for determining the liable party. Isotope measurements in geochemistry, combined with complimentary techniques for contaminant identification, have contributed significantly to source determination at polluted sites. In this work we have determined the intramolecular (13)C profiles of several molecules well-known as pollutants. By giving additional analytical parameters, position-specific isotope analysis performed by isotope ratio monitoring by (13)C nuclear magnetic resonance (irm-(13)C NMR) spectrometry gives new information to help in answering the major question: what is the origin of the detected contaminant? We have shown that isotope profiling of the core of a molecule reveals both the raw materials and the process used in its manufacture. It also can reveal processes occurring between the contamination site 'source' and the sampling site. Thus, irm-(13)C NMR is shown to be a very good complement to compound-specific isotope analysis currently performed by mass spectrometry for assessing polluted sites involving substantial spills of pollutant. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Lead isotopes in mantle derived xenoliths from Japan and South Africa

    International Nuclear Information System (INIS)

    Morioka, Masana; Kigoshi, Kunihiko.

    1978-01-01

    The lead isotopic compositions and the uranium, thorium and lead contents of eclogite and harzburgite inclusions from South African Kimberlite-pipes and lherzolite inclusions from Itinomegata crater, Japan and of their main mineral fractions have been determined. The observed 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 238 U/ 204 Pb in lherzolite samples from Itinomegata range from 17.9 to 18.2, from 15.1 to 15.5 and from 1.9 to 23, respectively. The results suggest that the lherzolites were of recent crystallization. The observed data on eclogite inclusions show no consistent pattern and suggest that they have a complicated history. The observed lead isotopic compositions of harzburgite inclusions from kimberlite-pipes are 206 Pb/ 204 Pb = 17.3 -- 19.0 and 207 Pb/ 204 Pb = 15.3 -- 15.6. These results are distributed in a wide range on two regression lines, suggesting that they had been formed from the same source material but with different ages or have been formed recently by mixing of two different source materials and host rock of kimberlite. (author)

  4. An improved FT-TIMS method of measuring uranium isotope ratios in the uranium-bearing particles

    International Nuclear Information System (INIS)

    Chen, Yan; Wang, Fan; Zhao, Yong-Gang; Li, Li-Li; Zhang, Yan; Shen, Yan; Chang, Zhi-Yuan; Guo, Shi-Lun; Wang, Xiao-Ming; Cui, Jian-Yong; Liu, Yu-Ang

    2015-01-01

    An improved method of Fission Track technique combined with Thermal Ionization Mass Spectrometry (FT-TIMS) was established in order to determine isotope ratio of uranium-bearing particle. Working standard of uranium oxide particles with a defined diameter and isotopic composition were prepared and used to review the method. Results showed an excellent agreement with certified values. The developed method was used to analyze isotope ratio of single uranium-bearing particle in swipe samples successfully. The analysis results of uranium-bearing particles in swipe samples accorded with the operation history of the origin. - Highlights: • The developed method was successfully applied in the analysis of real swipe sample. • Uranium-bearing particles were confined in the middle of track detector. • The fission tracks of collodion film and PC film could be confirmed each other. • The thickness of collodion film should be no more than about 60 μm. • The method could avoid losing uranium-bearing particles in the etching step.

  5. Determination of integrated neutron flux by the measurement of the isotopic ratios of cadmium and gadolinium

    International Nuclear Information System (INIS)

    Tomiyoshi, Irene Akemy

    1982-01-01

    In this work, the possibility of the indirect determination of the integrated neutron flux, through the change of isotopic ratios of cadmium and gadolinium was investigated. The samples of cadmium we/e gadolinium were irradiated in the IEA-Rl reactor. These elements were chosen because they have high thermal neutron absorption cross section which permit the change in the isotopic composition during a short irradiation time to be measured accurately. The isotopic ratios were measured with a thermionic mass spectrometer the silica-gel technique and arrangement with single filament were used for the cadmium analysis, where as the oxi - reduction technique and arrangement with double filaments were used for gadolinium analysis. The mass fractionation effects for cadmium and gadolinium were corrected respectively by the exponential and potential expansion of the isotopic fractionation factor per atomic mass unit. The flux values supplied by the Centro de Operacao e Utilizacao do Reator de Pesquisas do IPEN were extrapolated. These values and the integrated flux values obtained experimentally were compared. (author)

  6. Determination of isotope ratio of elements by mass distribution in molecules of varied chemical compounds

    International Nuclear Information System (INIS)

    Gladkikh, I.S.; Babichev, A.P.

    1999-01-01

    The procedure and program for calculation of isotope ratio of elements involving in the compound being studied using data of mass spectrometry were elaborated. The methods developed for the O 2 , SiH 4 , Cd(CH 3 ) 2 molecules were demonstrated for the illustration. The results of calculation provide support for the efficiency of the program and satisfactory reliability of the results during calculation of the isotope and complex compound concentrations. The program may be used for the estimation of the degree of nonequilibrium isotope distributions, it may indicate on the errors of the mass spectroscopy results [ru

  7. Evaluation of precision in measurements of uranium isotope ratio by thermionic mass spectrometry

    International Nuclear Information System (INIS)

    Moraes, N.M.P. de; Rodrigues, C.

    1977-01-01

    The parameters which affect the precision and accuracy of uranium isotopic ratios measurements by thermionic mass spectrometry are discussed. A statistical designed program for the analysis of the internal and external variances are presented. It was done an application of this statistical methods, in order to get mass discrimination factor, and its standard mean deviation, by using some results already published for 235 U/ 238 U ratio in NBS uranium samples, and natural uranium [pt

  8. Yields and isomeric ratio of xenon and krypton isotopes from thermal neutron fission of 235U

    International Nuclear Information System (INIS)

    Hsu, S.S.; Lin, J.T.; Yang, C.M.; Yu, Y.W.

    1981-01-01

    The experimental cumulative yields of 85 Kr/sup m/, 87 Kr, 88 Kr, 133 Xe/sup g/, 135 Xe/sup m/, and 135 Xe/sup g/ and the independent isomeric yield of 133 Xe/sup m/ in the thermal neutron fission of 235 U have been measured by the gas chromatographic method. The independent yields of 133 Xe/sup g/, 135 Xe/sup m/, and 135 Xe/sup g/ were deduced with the aid of 133 I and 135 I data. The isomeric yield ratios of 133 Xe and 135 Xe have been computed and compared with theoretical values since they have the same high spin state J = 11/2 - and low spin ground state J = 3/2 + . The influence of the shell effect on the fission isomeric yield ratio is discussed. From the measured independent yield of Xe isotopes plus the reported data, the Xe-isotopic distribution curve has been constructed. The curve is compared with the isotopic distribution curves of Xe isotopes formed in 11.5 GeV proton interactions with 238 U and Cs isotopes formed in 24 GeV proton interactions with 238 U. Upon fitting the yield curves we find that only those products with N/Z> or =1.48 fit a curve typical of a binary fission process

  9. Identification of Marchfeld asparagus using Sr isotope ratio measurements by MC-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Swoboda, S; Brunner, M; Boulyga, S F; Galler, P; Prohaska, T [University of Natural Resources and Applied Life Sciences, Department of Chemistry-VIRIS Project, Vienna (Austria); Horacek, M [Austrian Research Centers GmbH, Seibersdorf (Austria)

    2008-01-15

    This work focuses on testing and application of Sr isotope signatures for the fast and reliable authentication and traceability of Asparagus officinalis originating from Marchfeld, Austria, using multicollector inductively coupled plasma mass spectrometry after optimised Rb/Sr separation. The major sample pool comprises freeze-dried and microwave-digested asparagus samples from Hungary and Slovakia which are compared with Austrian asparagus originating from the Marchfeld region, which is a protected geographical indication. Additional samples from Peru, the Netherlands and Germany were limited in number and allowed therefore only restricted statistical evaluation. Asparagus samples from Marchfeld were harvested within two subsequent years in order to investigate the annual variation. The results show that the Sr isotope ratio is consistent within these 2 years of investigation. Moreover, the Sr isotope ratio of total Sr in soil was found to be significantly higher than in an NH{sub 4}NO{sub 3} extract, reflecting the mobile (bioavailable) phase. The isotope composition in the latter extract corresponds well to the range found in the asparagus samples in Marchfeld, even though the concentration of Sr in asparagus shows no direct correlation to the concentration of Sr in the mobile phase of the soil. The major question was whether the 'Marchfelder Spargel' can be distinguished from samples from the neighbouring countries of Hungary and Slovakia. According to our findings, they can be clearly (100%) singled out from the Hungarian samples and can be distinguished from the Slovakian asparagus samples with a probability of more than 80%. (orig.)

  10. Identification of Marchfeld asparagus using Sr isotope ratio measurements by MC-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Swoboda, S.; Brunner, M.; Boulyga, S.F.; Galler, P.; Prohaska, T. [University of Natural Resources and Applied Life Sciences, Department of Chemistry-VIRIS Project, Vienna (Austria); Horacek, M. [Austrian Research Centers GmbH, Seibersdorf (Austria)

    2008-01-15

    This work focuses on testing and application of Sr isotope signatures for the fast and reliable authentication and traceability of Asparagus officinalis originating from Marchfeld, Austria, using multicollector inductively coupled plasma mass spectrometry after optimised Rb/Sr separation. The major sample pool comprises freeze-dried and microwave-digested asparagus samples from Hungary and Slovakia which are compared with Austrian asparagus originating from the Marchfeld region, which is a protected geographical indication. Additional samples from Peru, the Netherlands and Germany were limited in number and allowed therefore only restricted statistical evaluation. Asparagus samples from Marchfeld were harvested within two subsequent years in order to investigate the annual variation. The results show that the Sr isotope ratio is consistent within these 2 years of investigation. Moreover, the Sr isotope ratio of total Sr in soil was found to be significantly higher than in an NH{sub 4}NO{sub 3} extract, reflecting the mobile (bioavailable) phase. The isotope composition in the latter extract corresponds well to the range found in the asparagus samples in Marchfeld, even though the concentration of Sr in asparagus shows no direct correlation to the concentration of Sr in the mobile phase of the soil. The major question was whether the 'Marchfelder Spargel' can be distinguished from samples from the neighbouring countries of Hungary and Slovakia. According to our findings, they can be clearly (100%) singled out from the Hungarian samples and can be distinguished from the Slovakian asparagus samples with a probability of more than 80%. (orig.)

  11. Direct isotope ratio measurement of uranium metal by emission spectrometry on a laser-produced plasma

    International Nuclear Information System (INIS)

    Pietsch, W.; Petit, A.; Briand, A.

    1995-01-01

    The method of Optical Emission Spectrometry on a Laser-Produced Plasma (OES/LPP) at reduced pressure has been studied for the determination of the uranium isotope ratio ( 235 U/ 238 U). Spectral profiles of the investigated transition U-II 424.437 nm show the possibility to obtain an isotopic spectral resolution in a laser-produced plasma under exactly defined experimental conditions. Spectroscopic data and results are presented. (author)