講　　題：Analytical strategies using combined isotopic signatures or multi - isotopic - dilution methods to ascertain the origine of wines and foods
講　　者：Olivier Donard /法國法蘭西學院院士

講　　題：Hg stable isotope and speciation to decipher marine Hg biogeochemistry and impact on marine life
講　　者：David Amouroux /法國國家科學研究中心所長

地　　點：甲子廳
日　　期：2024年12月17日(二)
時　　間：15:10~16:55

二位學者皆為當今此領域之頂尖學術研究者. 專精於分析與環境化學，利用感應耦合電漿多頻道質譜儀進行微量元素物種及同位素分析， 應用於環境、海洋、生物、食品和工業領域， 尤其專注於汞、硒、錫和鉛的生物地球化學循 環，目前研究對象包括海洋黑鮪、鳥類及其他 生物並葡萄酒等食品.

Analytical strategies using combined isotopic signatures or multi - isotopic - dilution methods to ascertain this origin of wines and foods.

Olivier F.X Donard, IPREM CNRS, Hélioparc, Pau, 64000, France

Wine is one of the oldest beverages consumed worldwide. Since beverages are among the foods most likely to be subject to fraudulent activities, wine traceability and authenticity represent key factors for quality assessment for the winemakers. This aspect is also of concern for both the producer and consumer protection. The geographical signature is related to the mineral signature of the soil. Since the grapes import mineral elements from the soil for their development, they then are, for one part, defining the basis of the “terroir”, tracing the soil and thus their geographical origin. Elements may also later be added by wine producers to either stimulate and protect the growth of the plant. As a result, the multi-elemental content of a wine is a strong testimony of its origin as well as of the process that resulted to make it available to the final consumer. Multi-elemental signatures are very well suited to the use of ICP-MS based methods. They are now extensively used to evaluate the trace element composition in foodstuffs and specifically wines. Their application for food traceability has been rapidly increased over the last decade.

After using the combination of 3 high precision isotopic systems of elements such as Sr, Pb and B and apply it to Champagne origin. Combined MC-ICP/MS determination are very efficient but long and costly. To further improve the discrimination potential of the multi-elemental signatures of wines, we have developed an original multi-isotopic dilution approach added directly as a spike simply prior detection by a QQQ-ICP/MS. This new approach allows to quantify simultaneously these 22 elements with an excellent precision on a routine basis that is usually less than 2% RSD. Other elements are quantified by the traditional calibration methods. This approach allows to address an extremely large array of elements, majors, minors and trace elements resulting from a most precise discrimination of origin. It allows to promote the development or an European data basis for European wines for the moment within the EU project TraceWindu.

This presentation will present the development of this new method, its analytical performances, and its application to discriminate the geographical origin of wines at the country or even at the regional level. We will present the original developments of wine discrimination using Artificial Intelligence and its innovation for data basis processing. It will be applied to an exceptionally long-term series of on specific prestigious Champagne that has been produced over a century. We will detail the different results obtained both with very high precision using MC - ICP/MS for Sr, Pb, B and Cu isotopes. Then the multi-elemental signatures obtained by multi-dilution QQQ-ICP/MS, will clearly major features that that Champagne like any other wine is a good mirror of the evolution of our environment. These approaches may also be used to other matrices originating from the soils.

Hg stable isotope and speciation to decipher marine Hg biogeochemistry and impact on marine life

David Amouroux, IPREM, CNRS, France

Mercury (Hg) is considered as a global pollutant and has a highly dynamic biogeochemistry in the environment due to its fast reactivity and chemical speciation changes. Hg has also seven stable isotopes which undergo mass dependent fractionation (MDF) during abiotic and biotic transformations. In addition, photochemical transformations can generate significant mass independent fractionation (MIF). A large range in MDF and MIF has been observed in a whole set of marine and biological samples making the combination of Hg molecular speciation and Hg isotopic signatures as a very promising tool. Hg stable isotopes signatures associated to its chemical form can be then used throughout the marine environment and along trophic chains, providing important insights into Hg biogeochemical cycling and exposure. This presentation present the importance of experimental and analytical investigations to understand Hg isotopic fractionation pathways and highlight some of our recent scientific findings on Hg isotopes in marine biogeochemical and ecological studies.