Environ. Sci. Technol. 2009, 43, 33–39
Tracing Mercury Contamination from the Idrija Mining Region (Slovenia) to the Gulf of Trieste Using Hg Isotope Ratio Measurements D E L P H I N E F O U C H E R * ,†N I V E S O G R I N C ‡ AND HOLGER HINTELMANN† Department of Chemistry, Trent University, 1600 West Bank Drive, Peterborough, Ontario, K9J 7B8, Canada, and Department of Environmental Sciences, Jozef Stefan Institute, Jamova 39, SI-1000 Ljubljana, Slovenia
Received June 26, 2008. Revised manuscript received October 10, 2008. Accepted October 20, 2008.
To demonstrate the power of precise isotope ratio measurements of Hg in environmental samples and, more particularly, to test the use of stable isotopes as distinct tracers of the contamination source, we investigated a well-documented system, the Hg mining region near Idrija, Slovenia. Sediments alongside the Idrijca River, the Socˇa/Isonzo River, and in the Gulf of Trieste were analyzed to determine the variation in Hg isotopic composition versus distance from the source. Similar Hg isotopic signatures were observed among samples collected from the rivers Idrijca, Socˇa/Isonzo, and around the river mouth in the Gulf of Trieste, suggesting that sediments throughout the watershed of the Socˇa/Isonzo River to the Gulf of Trieste are dominated by Hg exported from the headwaters of the Idrijca River. Only locations on the southern part of the gulf, outside the river plume, showed lower values of the isotopic composition comparable to the Hg isotopic signature of Adriatic Sea sediments. Using a simple binary mixing-model, we could demonstrate that all samples investigated in this study were a result of variable proportions of Hg originating from the Idrija region (progressively decreasing from >90% in the northern part to 98%, Aldrich) was prepared in 1.20 M HCl. Prior to use, the reductant solution was vigorously purged with Hg-free nitrogen for few hours to liberate any mercury. All acids were of analytical grade (HNO3 and HCl, certified ACS Plus, Fisher Scientific) and all samples, standard solutions, and reagents were diluted with high quality water that was provided by a Milli-Q purification system (Millipore, Bedford, U.S.) capable of producing 18.2 ΩM-grade water.
Results and Discussion Isotopic Composition of Mercury in Sediments. Spatial distribution of δ-values in surface sediments of the Socˇa/ Isonzo River, the Gulf of Trieste and the Adriatic Sea are presented in Figure 2 (for isotope ratio 202Hg/198Hg) and Supporting Information Table S1 (for isotope ratios 202Hg/ 198Hg, 201Hg/198Hg, 200Hg/198Hg, and 199Hg/198Hg). The isotopic composition in the sediments varied between δ202Hg ) -0.13 to -2.53‰. It is worth noting that, for all samples, the magnitude of the Hg fractionation per amu was constant and independent of the pair of Hg isotopes chosen. As seen in Figure 3 on the three-isotope plot δ201Hg vs δ202Hg, measured Hg isotopic composition plotted well against the theoretical mass-dependent fractionation line, demonstrating that sediments of this study were not subject to mass independent fractionation. So far, the only processes known to induce MIF are photoreduction of Hg(II) and photodemethylation (14). However, considering the very high Hg concentrations in Idrijca River sediments, photochemical processes would only affect a very minor fraction, and we would not expect a detectable mass independent Hg isotope ratio shift in this large Hg pool. Similar Hg isotopic compositions (mean δ202Hg ) -0.30 ( 0.11‰, n ) 16) were detected along the Idrijca-Socˇa/Isonzo fluvial system and around the mouth of the river in the Gulf of Trieste. An ANOVA test showed that there was no significant difference (P ) 0.22) in δ202Hg obtained among surface sediments originating from the Idrijca River (Travnik), collected along the river (Socˇa-Y12 and -Y1), from the estuary (Socˇa-Stn6 and -Stn8) of the Socˇa/Isonzo River, or in the northern and central regions of the Gulf of Trieste (GT-D6, GT-1, GT-3, GT-A4, GT-AA1, GT-CZ, and GT-A20). The erosion VOL. 43, NO. 1, 2009 / ENVIRONMENTAL SCIENCE & TECHNOLOGY
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FIGURE 3. Three-isotope plot δ201Hg vs δ202Hg. Isotopic compositions are reported in per mil (‰) relative to the Hg standard NIST 1641d. The solid line represents the theoretical mass-dependent fractionation line based on the exponential law (32) and using IUPAC atomic weight values: δ201Hg ) 0.7520 × δ202Hg. of contaminated soils, in which cinnabar accounts for more than 80% of the total Hg, is the most important source of Hg in the area (33, 34). Sediments throughout the watershed of the Idrijca and Socˇa/Isonzo River to the Gulf of Trieste (over a distance of more than 100 km) proved to have the same mercury isotopic signature, suggesting that Hg originating from a single source dominates these sites. Sediment samples showed an Hg isotopic composition very close to red cinnabar (δ202Hg ) -0.26 ( 0.12‰, P ) 0.60), which suggest that most Hg in the investigated sediments is predominantly red cinnabar rather than black metacinnabar. This observation supports previous studies (35, 36) using solid-phase-Hgthermo-desorption technique, which demonstrated a clear predominance of natural red cinnabar (compared to black metacinnabar and noncinnabar Hg compounds) in sediment samples taken between the city of Idrija and the Socˇa/Isonzo river mouth and in the Gulf of Trieste around the river delta. To our knowledge, this work represents the first attempt to assess the Hg isotopic composition of sediments heavily impacted by mining activities. Therefore, it is difficult to directly compare our results to previous studies. However, during the past few years, Hg isotopic signatures of cinnabar samples from various mines worldwide have been investigated (see Supporting Information Section S1.1). Previously published data (2) suggested an isotopic deviation for δ198Hg/ 204Hg of +0.04‰ (compared to Hg from the Almaden Mine) for cinnabar samples of the Idrija Mine, which would translate into a δ202Hg value of approximately -0.60‰ relative to NIST 1641d Hg. In contrast to the northern part and the fluvial system, sediments found in the southern region and on the fringe of the Gulf of Trieste (GT-A3, GT-A28 and GT-F1) showed a largely different (P < 0.0007 and P < 0.0001, respectively) and much lower isotopic composition (δ202Hg ranging from -1.19 to -2.53‰). Further away from the river mouth, Hg isotopic compositions tend to be closer (P ) 0.59) to the one observed for marine sediments of the Adriatic Sea (δ202Hg varying from -1.49 to -2.39‰). These results coincided with low total mercury contents suggesting that these areas of the Gulf are located outside the Socˇa/Isonzo River plume and are therefore less impacted by anthropogenic mercury. Extensive research has been carried out on measurements and models to describe and understand the spatial distribution and fate of mercury in the Gulf of Trieste. It has been 36
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shown that the spatial distribution in the basin is related to the distance from the riverine source creating a positive gradient of contamination from the southern to the northern sector of the Gulf (20-24). High mercury contents were found in the near shore sediments of the northern (Italian) sector and, particularly along the shoreline of two sides of the river delta. While maximum values were obtained within the Socˇa/ Isonzo River mouth and the northwestward littoral zone, they demonstrated that Hg contamination becomes progressively less extensive toward southern areas. Hg concentrations obtained in the southern part were found to be significantly lower and in some locations (southeast, Slovenia shoreline) very close to the estimated natural geochemical background value of the Mediterranean sediments (0.1 mg kg-1), suggesting that only a small amount of Hg from the Idrija region reaches this sector of the Gulf. Modeling studies (25-27) concluded that the transport and dispersion of Hg in the Gulf of Trieste are driven by the combined action of winds, Socˇa/Isonzo River flood events and by the water circulation system in the basin. Simulations showed that the export of Hg from the fluvial system is only effective with strong riverine flows, during which suspended matter is spread as a plume away from the river mouth into the coastal waters of Trieste. The water circulation in the Gulf is mostly affected by the anticlockwise northern Adriatic circulation system. Induced currents tend therefore to divert and transport the fluvial plume toward the west along the northern coast. Authors observed that wind conditions also play an important role and emphasize the dispersion of Hg in the Gulf. When strong wind blows, mercury rich sediments near the river mouth are partly resuspended and transported along the northwestern littoral. As a result of this flow pattern, most of the mercury coming into the Gulf of Trieste by the Socˇa/Isonzo River is transported along the northern shore toward the west and eventually, out of the Gulf (24). This scenario completely agrees with the extensive contamination observed in the northern part and also explains clearly why the southern area is less impacted by anthropogenic mercury. Ogrinc et al. (30) determined the elemental and Cand N-isotopic compositions of organic material in surface sediments of the Gulf of Trieste to distinguish between terrestrial and marine sources. They estimated that organic carbon of surficial sediments in the northern part of the Gulf and around the Socˇa/Isonzo River mouth are >90% of terrestrial origin. In contrast, sediments from the southern half of the basin (with the exception of the Koper and Piran bays) exhibited a predominance of marine organic matter arriving by currents from the Adriatic Sea. The isotopic characteristics of the Hg in sediments analyzed in this work are consistent with the distinction observed by all these authors between the northern and the southern part of the Gulf of Trieste. The general visualization of isotopic composition in the three-isotope plot (Figure 3) shows a systematic change in Hg isotope ratios. Endmembers are either dominated by Hg enriched with heavy isotopes (including sediments from the river, the estuary, and the northern part of the Gulf of Trieste) or by Hg showing a lower isotopic composition (including samples from the southern part of the basin). Only a couple of sediments originating from the southern shore and on the fringe of the Gulf of Trieste (GT-A3 and GT-A28, respectively) are situated in the center of the plot, suggesting significant contributions of both components. A picture starts to emerge, whereby Hg derived originally from the Idrija region is distinctively different from Hg present in uncontaminated samples of the Gulf of Trieste and the Adriatic Sea. In all samples analyzed during this work, the Hg isotope ratios in pristine sediments appeared enriched with lighter isotopes compared to Hg found at contaminated sites. This observation leads to the hypothesis that the magnitude of deviation from uncon-
taminated sediments will allow the calculation of the proportion of Hg from the Idrija region in the sediments of the Gulf of Trieste. In other terms, according to Hg isotopic fingerprints, one could expect to determine relative contribution of anthropogenic Hg in the environment. An alternative explanation for the measured Hg isotope deviations would be geochemical processes resulting in a fractionation of Hg isotopes. However, all known processes so far have shown enrichment of the residual solid phase with heavier isotopes. Microbial reduction (17), photoreduction (14), photodemethylation (14), methylation (18), and evasion processes (15, 16) preferentially act on the light Hg isotopes, which subsequently leave the system. The expected enrichment of heavy Hg isotopes in sediments is inconsistent with our observations in the Gulf of Trieste and the Adriatic Sea sediments. As well, a recent study has shown that partitioning of Hg between solid and dissolved phases does not generate measurable Hg isotope fractionation in natural environments (37). We therefore conclude that dilution of Idrija Hg with marine sediments is the cause for the measured variations. Binary Mixing-Model. Using simple binary mixing models, Pb isotope ratios have been used successfully to estimate Pb pollution sources in many ecosystems (38-40), and more particularly to investigate the impact of Pb mining on the surrounding environment (41-43). These models are based on the precise characterization of two distinctive sources of the element of interest (e.g., contaminant and natural background) and work satisfactory provided that each defined end-member has a significantly different isotopic composition. Before applying this principle to our case study, we simulated a binary mixing process in the laboratory by measuring the resulting Hg isotopic composition when two sediments of distinct isotopic fingerprint are mixed together. Due to constraints on available sample mass, this experiment could not be performed with sediments from the Gulf of Trieste area. Instead, we selected two samples from our sediment collection from the surroundings of the Murray Brook Mine located in New Brunswick, Canada. Both samples were carefully chosen to reproduce a similar situation: (i) a large discrepancy between the respective isotopic composition of the contaminant and the regional background components, and (ii) a Hg source (Sed-CONT.) enriched with heavier isotopes compared to the less contaminated sediment (Sed-NAT.). The two sediments were digested separately, and aliquots of the digests were combined prior to the measurement to create a series of solutions, each composed by different contributions of the two sediments. Hg isotopic measurements were compared to estimates obtained using the traditional isotopic mass balance mixing equations: δ202HgSAMP ) XCONT. × δ202HgCONT. + XNAT. × δ202HgNAT. (2) 1 ) XCONT. + XNAT.
(3)
XCONT. ) 1 - [Hg]NAT. ⁄ [Hg]SAMP.
(4)
where δ202HgSAMP., δ202HgCONT., and δ202HgNAT. are the isotopic deviation values of the sample, and of the Hg contaminant and regional background end-members, respectively; XCONT. and XNAT. are the respective anthropogenic and natural Hg fractions in the sample and [Hg]SAMP. and [Hg]NAT. correspond to the concentrations of total mercury in the considered sample and in the uncontaminated component, respectively. Hg isotopic compositions of end-members used for the simulation and results from the mixing experiment are compiled in Supporting Information Figure S1. For all four isotopic pairs investigated, measured Hg isotope ratios were nearly identical to those predicted by the binary mixing model. Isotopic composition of mixed solutions became progressively enriched in heavier isotopes (i.e., higher δ202Hg
FIGURE 4. Plot of δ202HgSAMP. (in ‰) vs (a) [Hg]SAMP. (in µg kg-1, log scale), and (b) 1/[Hg]SAMP. (mg kg-1). Diamonds represent the distribution of Hg isotopic compositions in sediments of the Idrijca River, the Socˇa/Isonzo River and the Gulf of Trieste, and triangles identify samples from the Adriatic Sea. The solid curve in a) was constructed from a binary mixing model between a background component [Hg]NAT. ) 0.07 mg kg-1, δ202HgNAT. ) -2.13 ( 0.46‰ (average between Adriatic Sea samples and GT-F1) and a contaminant source characterized by a δ202HgCONT. value of -0.26 ( 0.12‰ (red-cinnabar). The dashed line in (b) represents the linear regression for sediment samples. Grey filled symbols are outliers (GT-A20 as a diamond and Ad-STZB as a triangle, see discussion) that were not considered for the regression. values) as the contribution of the contaminant source increased. As anticipated, the correlation between δ-values and percentage of anthropogenic mercury proved to be perfectly linear and indistinguishable from the theoretically expected relationship (δ202HgSAMP. ) +4.11 × XCONT. - 3.40, R2 ) 0.999; δ201HgSAMP. ) +2.99 × XCONT. - 2.52, R2 ) 0.997; δ200HgSAMP. ) +2.05 × XCONT. - 1.69, R2 ) 0.998; δ199Hg SAMP. ) +0.87 × XCONT. - 0.75, R2 ) 0.988). Considering these results we can safely assume that samples with varying Hg isotope ratios mix conservatively and do not produce any analytical artifacts, which will therefore allow quantifying contributions from different Hg sources. The same binary mixing model was applied to predict δ-values in surface sediments of the Gulf of Trieste as a function of their mercury content (Figure 4a). A δ202Hg value of -0.26 ( 0.12‰ (mean ( 1 SD) corresponding to the isotopic signature of the red cinnabar (Supporting Information Table S1) was used as the contaminant end-member (δCONT.) in eq 2. For the characterization of the regional background component (δNAT.), all three sediments (Ad-STZB, Ad-STZ6, and Ad-STZ5) from the Adriatic Sea and the sample GT-F1 from the Gulf of Trieste were considered and averaged values of -2.13 ( 0.46‰ and 0.07 ( 0.05 mg kg-1 were applied to the δ202HgNAT. and [Hg]NAT. parameters, respectively. An acceptable agreement between simulated and measured deviations of Hg isotope ratios in surface sediments of the area was achieved with the binary mixing approach. A significant decrease of δ202Hg was characteristic for the less contaminated sediments and therefore consistent with a lower contribution of the anthropogenic component. With the exception of two samples (GT-A20 and Ad-STZB, see VOL. 43, NO. 1, 2009 / ENVIRONMENTAL SCIENCE & TECHNOLOGY
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additional discussion in Supporting Information Section, S1.2), we were able to reasonably explain all Hg isotope ratios as resulting from variable combinations of Hg originating from the Idrija mining area (Figure 4b). Indeed, the strong linear correlation between δ202HgSAMP. and 1/[Hg]SAMP. (δ202Hg ) -0.118 ((0.016) × 1/THg - 0.373 ((0.089), R2 ) 0.7492, P < 0.0001) revealed a close relationship between these two parameters. According to the model, Hg from the Idrija region contributes for more than 90% of the mercury found in the Socˇa/Isonzo River and in the northern part of the Gulf of Trieste. The southern area was the only region to exhibit a predominance of marine Hg with a percentage of Hg from the Idrija area of approximately 40-50%. In this study, we evaluated the possibility of employing Hg isotopic fingerprints as a tool to trace contamination sources in a relatively well understood Hg polluted marine environment, the Gulf of Trieste. Hg isotope ratios were successfully applied to track, differentiate and quantify Hg sources in the environment. Our results support many previous studies (19-22, 25, 27, 36), which concluded that most Hg found in the Socˇa/Isonzo River and the Gulf of Trieste originates from the Idrija region. By measuring Hg isotope ratios in environmental samples and applying a binary mixing model, we demonstrated that this methodology could provide evidence of anthropogenic impacts in heavily contaminated sediments. Without doubt the coupled concentration/isotope ratio approach has the potential to play an important role in investigating the distribution of mercury in ecosystems where Hg contents alone would not provide sufficient evidence. This work is a step forward in employing Hg isotope ratios as a tool to study and ultimately to better understand its biogeochemical cycling in the environment.
Acknowledgments This research project was funded by an NSERC grant to HH. We thank Jadran Faganeli and Nevenka Mikac for providing sediment samples.
Supporting Information Available Additional text, figure, and table. This material is available free of charge via the Internet at http://pubs.acs.org.
Literature Cited (1) Lauretta, D. S.; Klaue, B.; Blum, J. D.; Buseck, P. R. Mercury abundances and isotopic compositions in the Murchison (CM) and Allende (CV) carboneous chondrites. Geochim. Cosmochim. Acta 2001, 65 (16), 2807–2818. (2) Klaue, B.; Kesler, S. E.; Blum, J. D. Investigation of Natural Fractionation of Stable Mercury Isotopes by Multi-Collector Inductively Coupled Plasma Mass Spectrometry. Presented at the Annual International Conference on Heavy Metals in the Environment, Ann Arbor, MI, 2000. (3) Hintelmann, H.; Lu, S. Y. High precision isotope ratio measurements of mercury isotopes in cinnabar ores using multi-collector inductively coupled plasma mass spectrometry. Analyst 2003, 128, 635–639. (4) Smith, C. N.; Kesler, S. E.; Klaue, B.; Blum, J. D. Mercury isotope fractionation in fossil hydrothermal systems. Geology 2005, 33 (10), 825–828. (5) Blum, J. D.; Bergquist, B. A. Reporting of variations in the natural isotopic composition of mercury. Anal. Bioanal. Chem. 2007, 388, 353–359. (6) Evans, R. D.; Hintelmann, H.; Dillon, P. J. Measurement of high precision isotope ratios for mercury from coals using transient signals. J. Anal. At. Spectrom. 2001, 16, 1064–1069. (7) Biswas, A.; Blum, J. D.; Bergquist, B. A. Variation in natural mercury isotopic ratios of coal formations. Geochim. Cosmochim. Acta 2007, 71, A94. (8) Xie, Q.; Lu, S.; Evans, D.; Dillon, P.; Hintelmann, H. High precision Hg isotope analysis of environmental samples using gold trapMC-ICP-MS. J. Anal. At. Spectrom. 2005, 20 (6), 515–522. (9) Jackson, T. A.; Muir, D. C. G.; Vincent, W. F. Historical variations in the stable isotope composition of mercury in arctic lake sediments. Environ. Sci. Technol. 2004, 38 (10), 2813–2821. 38
9
ENVIRONMENTAL SCIENCE & TECHNOLOGY / VOL. 43, NO. 1, 2009
(10) Jackson, T. A.; Whittle, D. M.; Evans, M. S.; Muir, D. C. G. Evidence for mass-independent and mass-dependent fractionation of the stable isotopes of mercury by natural processes in aquatic ecosystems. Appl. Geochem. 2008, 23, 547–571. (11) Foucher, D.; Hintelmann, H. High-precision measurement of mercury isotope ratios in sediments using cold-vapor generation multi-collector inductively coupled plasma mass spectrometry. Anal. Bioanal. Chem. 2006, 384, 1470–1478. (12) Gehrke, G. E.; Blum, J. D.; Meyers, P. A. Hg accumulation in reducing sediments of the Mediterranean Sea: Trace metal and Hg isotope evidence. Geochim. Cosmochim. Acta 2007, 71, A314. (13) Laffont, L.; Sonke, J. E.; Foucher, D.; Hintelmann, H.; Behra, P.; Maurice-Bourgoin, L. Mercury stable isotope variations in a Bolivian watershed: evidence for mass-independent fractionation. Geochim. Cosmochim. Acta 2007, 71, A535. (14) Bergquist, B. A.; Blum, J. D. Mass-dependent and -independent fractionation of Hg isotopes by photoreduction in aquatic systems. Science 2007, 318, 417–420. (15) Zheng, W.; Foucher, D.; Hintelmann, H. Mercury isotope fractionation during volatilisation of Hg(0) from solution into the gas phase. J. Anal. At. Spectrom. 2007, 22, 1097–1104. (16) Estrade, N.; Carignan, J.; Sonke, J. E.; Donard, O. F. X. Mass independent fractionation of Hg isotopes during evaporation and condensation processes. Geochim. Cosmochim. Acta 2007, 71, A262. (17) Kritee, K.; Blum, J. D.; Johnson, M. W.; Bergquist, B. A.; Barkay, T. Mercury stable isotope fractionation during reduction of Hg(II) to Hg(0) by mercury resistant microorganisms. Environ. Sci. Technol. 2007, 41, 1889–1995. (18) Dzurko, M.; Foucher, D.; Hintelmann, H. Determination of compound-specific Hg isotope ratios from transient signals using gas chromatography coupled to multicollector inductively coupled plasma mass spectrometry (MC-ICP/MS). Anal. Bioanal. Chem. 2008, doi: 10.1007/s00216-008-2165-y. (19) Gosar, M.; Pirc, S.; Bidovec, M. Mercury in the Idrijca River sediments as a reflection of mining and smelting activities of the Idrija mercury mine. J. Geochem. Explor. 1997, 58, 125–131. (20) Horvat, M.; Covelli, S.; Faganeli, J.; Logar, M.; Mandiæ, V.; Rajar, ˇ agar, D. Mercury in contaminated coastal R.; Sˇirca, A.; Z environments; a case study: the Gulf of Trieste. Sci. Total Environ. 1999, 237/238, 43–56. (21) Hines, M. E.; Horvat, M.; Faganeli, J.; Bonzongo, J. C. J.; Barkay, T.; Major, A. B.; Scott, K. J.; Bailey, E. A.; Warwick, J. J.; Lyons, W. B. Mercury biogeochemistry in the Idrija River, Slovenia, from above the mine into the Gulf of Trieste. Environ. Res. 2000, 83, 129–139. (22) Covelli, S.; Faganeli, J.; Horvat, M.; Brambati, A. Mercury contamination of coastal sediments as the result of long-term cinnabar mining activity (Gulf of Trieste, northern Adriatic Sea). Appl. Geochem. 2001, 16, 541–558. (23) Covelli, S.; Piani, R.; Kotnik, J.; Horvat, M.; Fraganeli, J.; Brambati, A. Behaviour of Hg species in a microtidal deltaic system: the Isonzo River mouth (northern Adriatic Sea). Sci. Total Environ. 2006, 368 (1), 210–223. (24) Covelli, S.; Piani, R.; Acquavita, A.; Predonzani, S.; Fraganeli, J. Transport and dispersion of particulate Hg associated with a river plume in coastal Northern Adriatic environments. Mar. Pollut. Bull. 2007, 55, 436–450. ˇ agar, D.; Knap, A.; Warwick, J. J.; Rajar, R.; Horvat, M.; cˇetina, (25) Z M. Modelling of mercury transport and transformation processes in the Idrijca and Socˇa river system. Sci. Total Environ. 2006, 368 (1), 149–163. ˇ ibret, G.; Gosar, M. Calculation of the mercury accumulation (26) Z in the Idrijca River alluvial plain sediments. Sci. Total Environ. 2006, 368 (1), 291–297. ˇ agar, D.; Sˇirca, A.; Horvat, M. Three-dimensional (27) Rajar, R.; Z modelling of mercury cycling in the Gulf of Trieste. Sci. Total Environ. 2000, 260, 109–123. (28) Meischner, D.; Rumohr, J. A light-weight high-momentum gravity corer for subaqueous sediments. Senckenbergiana Marit. 1974, 6, 105–117. (29) Horvat, M. Mercury analysis and speciation. In Sources, Fluxes and Mass Balances NATO ASI Series 2, Environment; Baeyens, W., Ebinghaus, R., Vasiliev, O., Eds; Kluwer: Dordrecht, 1996; Vol. 21, pp 1-31. (30) Ogrinc, N.; Fontolan, G.; Faganeli, J.; Covelli, S. Carbon and nitrogen isotope compositions of organic matter in coastal marine sediments (the Gulf of Trieste, N Adriatic Sea): indicators of sources and preservation. Mar. Chem. 2005, 95, 163–181.
(31) Klaue, B.; Blum, J. D. Trace analyses of arsenic in drinking water by inductively coupled plasma mass spectrometry: high resolution versus hydride generation. Anal. Chem. 1999, 71, 1408– 1414. (32) Albare`de, F.; Telouk, P.; Blichert-Toft, J.; Boyet, M.; Agranier, A.; Nelson, B. Precise and accurate isotopic measurements using multiple-collector ICPMS. Geochim. Cosmochim. Acta 2004, 68 (12), 2725–2744. (33) Kocman, D.; Horvat, M.; Kotnik, J. Mercury fractionation in contaminated soils from the Idrija mercury mine region. J. Environ. Monit. 2004, 6, 696–703. (34) Gosar, M.; Sˇajn, R.; Biester, H. Binding of mercury in soils and attic dust in the Idrija mercury mine area (Slovenia). Sci. Total Environ. 2006, 369, 150–162. (35) Biester, H.; Gosar, M.; Mu ¨ ller, G. Mercury speciation in tailings of the Idrija mercury mine. J. Geochem. Explor. 1999, 65, 195– 204. (36) Biester, H.; Gosar, M.; Covelli, S. Mercury speciation in sediments affected by dumped mining residues in the drainage area of the Idrija mercury mine, Slovenia. Environ. Sci. Technol. 2000, 34, 3330–3336. (37) Foucher, D.; Hintelmann, H.; Al, T. Hg Isotope Fractionation in Waters and Sediments of the Murray Brook Mine Watershed, Tracing Mercury Contamination and Transformation; New Brunswick, Canada, in preparation. (38) Monna, F.; Lancelot, J.; Croudace, I. W.; Cundy, A. B.; Lewis, J. T. Pb isotopic composition of airbone particulate material
(39)
(40)
(41)
(42)
(43)
from France and the southern United Kingdom: implications for Pb pollution sources in urban areas. Environ. Sci. Technol. 1997, 31, 2277–2286. Aberg, G.; Charalampides, G.; Fosse, G.; Hjelmseth, H. The use of Pb isotopes to differentiate between contemporary and ancient sources of pollution in Greece. Atmos. Environ. 2001, 35, 4609–4615. Weiss, D. J.; Kober, B.; Dolgopolova, A.; Gallagher, K.; Spiro, B.; Le Roux, G.; Mason, T. F. D.; Kylander, M.; Coles, B. J. Accurate and precise Pb isotope ratio measurements in environmental samples by MC-ICP-MS. Int. J. Mass Spectrom. 2004, 232, 205– 215. Monna, F.; Hamer, K.; Le´veˆque, J.; Sauer, M. Pb isotopes as a reliable marker of early mining and smelting in the Northern Harz province (Lower Saxony, Germany). J. Geochem. Explor. 2000, 68, 201–210. Nova´k, M.; Emmanuel, S.; Vile, M. A.; Erel, Y.; Ve´ron, A.; Pacˇes, T.; Wieder, R. K.; Vaneˇcˇek, M.; Sˇteˇpa´nova´, M.; Brˇ´ızova´, E.; Hovorka, J. Origin of lead in eight central European peat bogs determined from isotope ratios, strengths, and operation times of regional pollution sources. Environ. Sci. Technol. 2003, 37 (3), 437–445. Ettler, V.; Mihaljevicˇ, M.; Koma´rek, M. ICP-MS measurements of lead isotopic ratios in soils heavily contaminated by lead smelting: tracing the sources of pollution. Anal. Bioanal. Chem. 2004, 378, 311–317.
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