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The (87)Sr/(86)Sr isotope ratios were measured on grape, wine and soil samples collected in 13 commercial vineyards located in three major wine producing areas of Quebec (Canada). The soils yield Sr isotope ratios that are intimately related to the local geology and unambiguously discriminate the different producing areas. A strong relationship exists between the (87)Sr/(86)Sr isotope ratios of the wine and the grapes. This suggests that the vinification process does not alter the overall Sr budget. Although the Sr isotope ratios of the grapes do not show a strong correlation with the bulk Sr isotope composition of the soil, they do correlate strongly with the Sr isotope composition contained in the labile fraction of the soil. This indicates that the labile fraction of the soil represents the Sr reservoir available to the plant during its growth. This study demonstrates that the Sr isotope approach can be used as a viable tool in forensic science for investigating the provenance of commercial wines., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The isotope ratios of strontium (Sr) and lead (Pb) in water derive from local geology and their isotopic signature can be linked to the age and type of underlying bedrocks and soils (if applicable), and are transferred up the food-chain. Both elements are transferred to human blood through diet and water, and some of it will ultimately be incorporated into the hair structure, making Sr and Pb isotopes interesting tools for tracing human mobility. In this study, we analyzed both the elemental concentration and isotope ratios of Sr and Pb from four different women of different ages to monitor their permanent relocation from central France to Eastern Canada during the summer 2012. For comparison, we also characterized bulk hair samples of sedentary individuals and local tap waters from their regions of origin and of settlement. Our results indicate that the 87Sr/86Sr and 206Pb/204Pb ratios are significantly modified by the change of environment, but also confirm that human hair compositions are impacted by other external factors (such as dust). Sr and Pb isotope systematics demonstrate their added value for detecting human mobility, but require further studies to better constrain the main sources and processes controlling their respective budgets in human hair for provenancing purposes., (Copyright © 2014 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.)

Bioindicators, by naturally cumulating the impacts of chemical contaminants over time, have demonstrated their added value in evaluating environmental quality. We studied Pb, Sr and Os isotope systematics from Cladonia rangiferina lichens collected along a transect between two smelting complexes located in Rouyn-Noranda and Sudbury (Canada) to identify sources of these metals in the Abitibi region and to delineate the extent of their respective emission plumes. Results show that metals present in the study area are explained by the contamination of the regional background by deposition from the atmospheric emissions of the different smelters over distances up to 250 km. A rough estimate of the respective metal contributions of each smelter to the lichen samples was calculated. At low metal concentrations, lichen samples indicate that dispersion plumes may differ for the Pb and Os contamination, perhaps to be linked to differential volatility. [ABSTRACT FROM AUTHOR]

The rare earth element (REE) concentrations and the neodymium (Nd) and strontium (Sr) isotope compositions of the detrital fraction and authigenic Fe Mn oxyhydroxide coatings of marine sediments may provide valuable information for better understanding the pathways of weathering inputs and estuarine and coastal exchange processes on different time scales. Here, we present the REE concentrations and 143Nd/144Nd (expressed in epsilon units, εNd) and 87Sr/86Sr ratios of detrital and authigenic (leached Fe Mn oxyhydroxides) fractions from sediment core-top samples and of estuarine water samples collected in the Estuary and Gulf of St. Lawrence (EGSL) and continental shelf off southeastern Canada. The REE distribution patterns, εNd values, and 87Sr/86Sr isotopic values from the detrital fraction allow for the discrimination of sediment from continental sources in the EGSL. Sediments in the Baie des Chaleurs and on the continental shelf, which have εNd values ranging from −14.3 to −16, 87Sr/86Sr values ranging from 0.72708 to 0.71475, and low La/Yb and Gd/Yb ratios, are mainly supplied by the early Paleozoic Appalachian Mountains. In contrast, sediments in the Laurentian and Esquiman channels (εNd = −18.7 to −21.8, 87Sr/86Sr = 0.72068 to 0.72607, and high La/Yb and Gd/Yb ratios) come from the Grenvillian metamorphic rocks in the Canadian Shield, and surface sediments on the southern Labrador Shelf (εNd = −28.7, 87Sr/86Sr = 0.73062, and high La/Yb and Gd/Yb ratios) mainly originate from the Hudson Strait and Baffin Bay. The εNd values obtained from estuarine water samples and bulk sediment leachates are unradiogenic, with values ranging between −18.9 and − 21.7 and between −16.1 and − 27.2, respectively. Based on these results and the dissolved REE concentrations, we speculate that salt-induced coagulation of colloidal matter, dissolution of lithogenic sediments from the adjacent continents (notably from the erosion of the Grenville Province on the North Shore), bottom scavenging within the nepheloid layer, and brine rejection during sea ice formation significantly influence the distribution of REEs and the authigenic εNd signal throughout the water column in the EGSL. Overall, our results both underscore the fact that caution must be exercised when interpreting authigenic εNd records due to bottom water-mass mixing in estuarine and coastal marine environments and highlight the potential of REE and Nd Sr isotope compositions in investigating changes in sediment sources and transport pathways in the EGSL. • εNd, 87Sr/86Sr and REE records of estuarine waters and sediments are presented. • Detrital εNd, La/Yb and Gd/Yb allow for tracking changes in detrital provenance. • All εNd signals reflects unradiogenic isotopic signatures from the Canadian Shield. • Dissolution of the labile mineral phases influences the dissolved REE distribution. • Particle-scavenging and brine rejection redistribute REEs within the water column. [ABSTRACT FROM AUTHOR]

Soils are a crucial interface of Earth's Critical Zone, responsible for the biogeochemical cycling of mineral nutrients. While the sources of essential nutrients such as Ca (and Sr) in plants have been widely studied, the processes by which these nutrients are transferred from the soil to the plants is less clear. We present new evidence for systematic nutrient fractionation between soils, grapes and wines from five vineyards from the Quebec terroir (Canada) using the novel stable Sr (δ88/86Sr) isotope system. We coupled this approach with traditional radiogenic 87Sr/86Sr measurements on the same samples (bulk soils, labile fraction of these soils, whole grapes, and wines) from five vineyards from the Quebec terroir (Canada) to ensure that variations in δ88/86Sr values were provoked by processes involved in Sr transfer instead of mixing between different sources. The δ88/86Sr values generally decrease from the bulk to the labile fractions of the soils to the grapes. A decrease in the difference between the soil fractions (Δ88/86Sr bulk-labile) with increasing δ88/86Sr values in the labile fraction is interpreted to reflect increasing pedogenic mineral precipitation and higher soil fertility. The depleted δ88/86Sr values of the grapes are consistent with a preferential uptake of lighter isotopes by plants. This effect is magnified in soils showing higher secondary mineral precipitation. An increase in the δ88/86Sr values from the grapes to the wines reflects the separation of the skin/seeds and the juice (pulp enriched in 88Sr) in the winemaking process. This mixing relationship is supported by a correlation between the Sr concentrations and the δ88/86Sr values of the wines and grapes. These findings suggest promising new applications of stable Sr isotopes values for studying soil fertility and the impact of nutrient availability for plant growth in agricultural ecosystems as well as the impact of the maceration processes in the production of wine. The overall similarity of 87Sr/86Sr ratios of the labile soil fractions, grapes and wines from the same vineyard support the hypothesis of a same Sr source, from the soil solution to its transfer to the grape and wine and confirm the potential of the 87Sr/86Sr ratios as a proxy for geographic provenance of wine. However, slightly lower 87Sr/86Sr ratios in the grape pulps (by 0.00040 on average compared to the skins and seeds) suggest that the sources of nutrients available for plant uptake vary during the vegetative cycle. The grape seeds and skins formed in the early growth cycle are characterized by rapid growth due to enhanced rhizosphere activity (enhanced mineral dissolution) providing higher nutrient levels. The enhanced mineral solubility results in higher 87Sr/86Sr ratios in the skin and seeds derived from enhanced dissolution of 87Sr-enriched silicate minerals. In contrast, the pulp develops later in the growth cycle when rhizosphere activity and mineral solubility is reduced, resulting in a lesser contribution from silicate minerals and thus reflect a higher proportion of dissolved carbonate contributing to the lower 87Sr/86Sr ratios of the pulps. [ABSTRACT FROM AUTHOR]