The marine biogeochemistry of zinc isotopes

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2007Zinc (Zn) stable isotopes can record information about important oceanographic processes. This thesis presents data on Zn isotopes in anthropogenic materials, hydrothermal fluids and minerals, cultured marine phytoplankton, natural plankton, and seawater. By measuring Zn isotopes in a diverse array of marine samples, we hope to understand how Zn isotopes are fractionated in the oceans and how Zn isotopes may be used as tracers of marine biogeochemical processes. Common forms of anthropogenic Zn had δ66Zn from +0.08‰ to +0.32‰, a range similar to Zn ores and terrigenous materials. Larger variations were discovered in hydrothermal fluids and minerals, with hydrothermal fluids ranging in δ66Zn from 0.02‰ to +0.93‰, and chimney minerals ranging from -0.09‰ to +1.17‰. Lower-temperature vent systems had higher δ66Zn values, suggesting that precipitation of isotopically light Zn sulfides drives much of the Zn isotope fractionation in hydrothermal systems. In cultured diatoms, a relationship was discovered between Zn transport by either high-affinity or low-affinity uptake pathways, and the magnitude of Zn isotope fractionation. We established isotope effects of δ66Zn = -0.2‰ for high-affinity uptake and δ66Zn = -0.8‰ for low-affinity uptake. This work is the first to describe the molecular basis for biological fractionation of transition metals. Biological fractionation of Zn isotopes under natural conditions was investigated by measuring Zn isotopes in plankton collected in the Peru Upwelling Region and around the world. Seawater dissolved Zn isotopes also reflect the chemical and biological cycling of Zn. The δ66Zn of deep seawater in the North Pacific and North Atlantic is about 0.5‰, and the dissolved δ66Zn gets lighter in the upper water column. This is unexpected based our observations of a biological preference for uptake of light Zn isotopes, and suggests that Zn transport to deep waters may occur by Zn adsorption to sinking particles rather than as primary biological Zn. The thesis, by presenting data on several important aspects of Zn isotope cycling in the oceans, lays the groundwork for further use of Zn isotopes as a marine biogeochemical tracer.This research was funded by NSF Research Grants OCE-0002273 and OCE-0326689, the Martin Family Society Fellowship for Sustainability, the Woods Hole Ocean Ventures Fund, and Arunas and Pam Chesonis through an MIT Earth Systems Initiative Ignition Grant

A study into the effects of pyrolysis fuels, pyrolysis conditions and the identification of chemical markers in grapes and wine as smoke taint

Taxonomically distinct vegetation fuels were used to generate smoke for fumigating grapevines to examine the influence of lignin makeup on smoke taint compounds that accrue in wine. Vegetation type had no effect on taint accumulation. Phenol, m-cresol and p-cresol glycoconjugates were closely associated with harsh smoke taint descriptors. While cultivars had similar smoke uptake sensitivity, winemaking method had distinct impact: red winemaking releases 80% of grape phenols compared to 20-35% for white winemaking

Implementation of Sensors and Artificial Intelligence for Environmental Hazards Assessment in Urban, Agriculture and Forestry Systems

The implementation of artificial intelligence (AI), together with robotics, sensors, sensor networks, Internet of Things (IoT), and machine/deep learning modeling, has reached the forefront of research activities, moving towards the goal of increasing the efficiency in a multitude of applications and purposes related to environmental sciences. The development and deployment of AI tools requires specific considerations, approaches, and methodologies for their effective and accurate applications. This Special Issue focused on the applications of AI to environmental systems related to hazard assessment in urban, agriculture, and forestry areas

Interim Design Report

The International Design Study for the Neutrino Factory (the IDS-NF) was established by the community at the ninth "International Workshop on Neutrino Factories, super-beams, and beta- beams" which was held in Okayama in August 2007. The IDS-NF mandate is to deliver the Reference Design Report (RDR) for the facility on the timescale of 2012/13. In addition, the mandate for the study [3] requires an Interim Design Report to be delivered midway through the project as a step on the way to the RDR. This document, the IDR, has two functions: it marks the point in the IDS-NF at which the emphasis turns to the engineering studies required to deliver the RDR and it documents baseline concepts for the accelerator complex, the neutrino detectors, and the instrumentation systems. The IDS-NF is, in essence, a site-independent study. Example sites, CERN, FNAL, and RAL, have been identified to allow site-specific issues to be addressed in the cost analysis that will be presented in the RDR. The choice of example sites should not be interpreted as implying a preferred choice of site for the facility

Accumulation of Platinum Group Elements by the Marine Microalga, Chlorella stigmatophora

Very little information exists on the marine biogeochemistry of Rh, Pd and Pt, or the platinum group elements (PGE), an emerging group of contaminants whose principal emissions are associated with the abrasion of the catalytic converter in motor vehicles and chemotherapy drugs discharged in hospital wastes. In this study, Rh(III), Pd(II) and Pt(IV) were added individually and in combination to cultures of the marine microalga, Chlorella stigmatophora, maintained in coastal seawater at 15oC and under fluorescence lighting both in the presence and absence of trace nutrients (e.g. Fe, Co, Zn and EDTA). The accumulation of PGE was established under varying conditions (pH, algal biomass, PGE concentration, time) by ICP-MS analysis of seawater and nitric acid digests and EDTA washes of the alga, the latter giving a measure of PGE adsorption by C. stigmatophora. Under all conditions the extent of accumulation was in the order: Rh > Pd >> Pt. In short-term (24-h) exposures, accumulation isotherms were quasi-linear up to PGE concentrations of 30 ug L-1, although Pd displayed convexity, hence saturation of available binding sites, at greater concentrations. The pH, adjusted between about 5.5 and 9.5 by addition of acid or base, did not have a great impact on PGE accumulation, with Rh displaying a moderate increase in accumulation and Pd a moderate reduction with increasing pH. More important, all PGE displayed a significant reduction in accumulation on a weight-normalized basis with increasing concentration of algae, an effect not reported for metal-marine algal interactions previously in the literature. Longer-term experiments showed that the rates of both overall accumulation and internalization were greatest for Pd and least for Pt. Consistent with this observation, the toxicity to C. stigmatophora evaluated by both pigment content and growth rate, was significantly greater for Pd than for Pt. Differences in the biogeochemical behaviours among the PGE are attributed to differences in their aqueous speciation in seawater, different affinities for the algal surface, different tendencies to cross the cell membrane, and especially with regard to Pd and Pt, differences in the rates of these interactions. Thus, although the equilibrium chemistries of Pd and Pt are very similar, their differential biogeochemistries are the result of kinetic constraints on reactions involving the latter. Because the environmental concentrations of PGE are predicted to increase with increasing emissions from vehicles and hospitals, the results of this study make an important contribution to an improved understanding of the likely effects and fates of these emerging contaminants in the marine environment. The results are also more generally important to an improved understanding of the interactions of trace metals with microalgae in seawater

The importance of long-term capture-mark-recapture archives for wildlife monitoring and research: Two examples from bat populations

Long-term capture-mark-recapture (CMR) projects provide useful data to study and monitor wildlife. Specifically, CMR data can help identify how an animal interacts with its environment and how these interactions change throughout its life. In this thesis, I use data and sample archives from temperate hibernating bats captured and tagged as part of a long-term project in Newfoundland and Labrador, Canada. In Chapter 2, I use fur collected from adult female captured multiple times from 2012-2017 to investigate age dependent changes in the concentration of the toxic compound, methylmercury (MeHg). Results suggest total mercury concentrations, which are highly correlated with MeHg, decrease with age in the fur of adult female bats. This pattern indicates that adult female bats can eliminate enough MeHg from their tissues to have steady or decreasing concentrations in their fur. In Chapter 3, I use forearm measurements taken by multiple observers from captured and tagged . and to quantify the measurement error and observer bias associated with this morphometric variable. Results suggest measurement error can add enough variation to mask relationships between forearm length and related variables. Further, observer bias can cause type I errors when comparing populations with small differences in forearm length that were measured by different observers. These two studies exemplify the use of long-term CMR projects as an invaluable tool to assess research techniques, study wildlife biology, and monitor ecological changes

Devising quality assurance procedures for assessment of legacy geochronological data relating to deglaciation of the last British-Irish Ice Sheet

This contribution documents the process of assessing the quality of data within a compilation of legacy geochronological data relating to the last British-Irish Ice Sheet, a task undertaken as part of a larger community-based project (BRITICE-CHRONO) that aims to improve understanding of the ice sheet's deglacial evolution. As accurate reconstructions depend on the quality of the available data, some form of assessment is needed of the reliability and suitability of each given age(s) in our dataset. We outline the background considerations that informed the quality assurance procedures devised given our specific research question. We describe criteria that have been used to make an objective assessment of the likelihood that an age is influenced by the technique specific sources of geological uncertainty. When these criteria were applied to an existing database of all geochronological data relating to the last British-Irish Ice Sheet they resulted in a significant reduction in data considered suitable for synthesis. The assessed data set was used to test a Bayesian approach to age modelling ice stream retreat and we outline our procedure that allows us to minimise the influence of potentially erroneous data and maximise the accuracy of the resultant age models

Investigações da biogeoquímica isotópica de Zn em áreas costeiras e de mangue

Tese (doutorado)—Universidade de Brasília, Instituto de Geociências, Programa de Pós-Graduação em Geologia, 2016.Zonas costeiras do mundo afora estão sob forte pressão da contaminação antrópica, uma vez que a população global e as atividades econômicas concentram-se ao longo das costas e dos estuários. A ameaça de contaminantes nestes ecossistemas torna imperativo o desenvolvimento de ferramentas capazes de detectar mudanças biogeoquímicas no intuito de auxiliar a prevenção, o monitoramento e a predição de riscos em estudos ambientais. Assim, esta tese investiga a geoquímica isotópica do Zinco (Zn) de forma a desenvolver uma ferramenta capaz de traçar fontes naturais e antrópicas, identificar processos biogeoquímicos e possibilitar o biomonitoramento de contaminação metálica em áreas costeiras e mangues. Para este fim, composições isotópicas de Zn foram determinadas em várias amostras naturais coletadas na baía de Sepetiba (sudeste do Brasil), um estuário lagunar impactado por uma costa industrializada próximo à cidade do Rio de Janeiro. Esta baía constitui um laboratório natural ideal para avaliação do sistema isotópico de Zn para questões ambientais, pois apresenta importantes ecossistemas de interesse comercial e ecológico – estuários, mangues e planícies de maré – ameaçados pela contaminação de uma antiga atividade galvânica e outras fontes difusas. As amostras coletadas incluem testemunhos de sedimento, sedimentos superficiais de mangue, folhas de árvores de mangue, tecido mole de moluscos bivalves (ostras e mexilhões) e rochas. Minérios do depósito de Vazante (Minas Gerais, Brasil), também foram coletadas para representar a matéria-prima utilizada na antiga atividade galvânica. Primeiramente, um trabalho laboratorial inicial estabeleceu um método acurado e preciso para determinações isotópicas de Zn em amostras naturais por espectrometria de massa com plasma indutivamente acoplado e multi-coletor (MC-ICP-MS). Análises espaciais e temporais dos resultados das composições isotópicas de Zn de amostras de sedimento e rocha se ajustam à um modelo de mistura entre três membros finais: i) materiais continentais carreados pelos rios; ii) fontes marinhas; e iii) uma fonte antropogênica principal associada a antigos rejeitos de galvanoplastia lançados na baía. Testemunhos de sedimento coletados na planície lamosa mostraram altas correlações entre as composições isotópicas de Zn e fator de enriquecimento de Zn, sugerindo (i) uma boa preservação dos registros isotópicos de fontes naturais e antrópicas, e (ii) ausência de fracionamento isotópicos significativos durante o transporte de sedimentos ou em reações diagenéticas pós-deposição no sistema estuarino. O testemunho de sedimento coletado em um mangue localizado na zona impactada pelos antiga atividade galvânica apresentou níveis de Zn acima de 4% (peso seco) e preservou as assinaturas isotópicas dos rejeitos da galvanoplastia. Entretanto, há evidências de que processos biogeoquímicos promovidos por processos hidrodinâmicos, biotubarção e rizosfera podem alterar sutilmente as assinaturas isotópicas em algumas camadas do perfil. Cálculos baseados neste modelo de mistura quantificaram contribuições da principal fonte antropogênica variando de valores desprezíveis em períodos pré-industriais até 80% durante períodos da atividade eletrogalvânica entre as décadas de 60 e 90. A sistemática dos isótopos de Zn de bivalves não foi associada a processos de mistura de fonte. Em vez disso, suas assinaturas bioisotópicas parecem estar relacionadas às diferentes rotas de bioacumulação, i.e, via incorporação da fase dissolvida ou particulada. A hipótese é que na zonas severamente impactadas pelos antigos rejeitos da galvanoplastia, os bivalves incorporam altas concentrações de Zn na fase dissolvida através das brâquias, enquanto fora desta zona, estes organismos incorporam o Zn lábil ligado ao material partículado durante a digestão. Assinaturas isotópicas de Zn de folhas também não permitiram a identificação de fontes por causa do significativo fracionamento isotópico durante a incorporação do Zn pelas raízes. Folhas de ambientes contaminados apresentaram padrões isotópicos de Zn diferentes dos padrões encontrados em folhas de áreas pouco ou não contaminadas. Estes padrões podem estar associados à ativação de mecanismos de tolerância pelas árvores do mangue onde as concentrações de Zn atingem concentrações tóxicas. Em conclusão, as composições isotópicas de Zn de amostras abióticas como sedimentos são efetivas para detectar mudanças biogeoquímicas desencadeadas por atividades antrópicas e, portanto, podem ser úteis para dar suporte à prevenção, ao monitoramento e à predição de riscos em áreas impactadas pela contaminação metálica. Amostras biológicas de moluscos bivalves e folhas de árvores de mangue não são adequadas para traçar fontes, porém, os distintos padrões isotópicos de Zn encontrados para amostras de ambientes altamente contaminados são promissores para aplicar isótopos de Zn como biomarcadores de reações metabólicas e efeitos fisiológicos associados à contaminação metálica. Futuras investigações são necessárias para compreender as relações entre a especiação de Zn, mecanismos de incorporação e as assinaturas bioisotópicas de tecidos de bivalves e folhas.Coastal areas worldwide are under strong pressure from anthropogenic contamination, as most of the global population and of economic activities are concentrated along the coasts and estuaries. The threaten of contaminant releasing into these ecosystems makes imperative the development of tools capable of detecting biogeochemical changes in order to help prevention, monitoring and prediction of risks in environmental studies. In this way, this thesis investigates the isotope biogeochemistry of Zinc (Zn) in order to develop a tool capable of tracing natural and anthropogenic sources, identifying biogeochemical processes and enabling the biomonitoring of metal contamination in coastal areas and mangroves. To this end, Zn isotopes compositions were determined in several natural samples collected from Sepetiba bay (southeastern Brazil), an estuarine-lagoon impacted by an industrialized coastal area near Rio de Janeiro. This bay constitutes an ideal natural laboratory for evaluating the Zn isotopic system to environmental issues, since it hosts important ecosystems of commercial and ecological interest – estuaries, mangroves and tidal flats – threaten by the metal contamination resultant of old electroplating activity and other anthropogenic diffuse sources. The collected samples include sediment cores, surface mangrove sediments, suspended particulate matter (SPM), leaves of mangrove’s trees, tissues of bivalve mollusks (oysters and mussels) and rocks. Ores from Vazante deposit, Brazil were collected to represent the raw material used in the old electroplating industry. Firstly, an initial laboratory work established a method for accurate and precise determinations of Zn isotope compositions in natural samples by multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS). Spatial and temporal analysis of Zn isotope compositions of sediment and rock samples fits well in a model of mixing between three main end-members: i) continental materials brought via rivers; ii) marine sources; and iii) a major anthropogenic source associated to the old electroplating wastes released into the bay. Sediment cores collected in the mud flat showed high correlation between Zn isotope compositions and Zn enrichment factors, suggesting (i) good preservation of isotopic records of natural and anthropogenic sources and (ii) no significant isotopic fractionation during sediment transport or as a result of diagenetic reactions post-deposition in the estuarine system. The sediment core sampled from a mangrove located in the zone impacted by the old electroplating activity presented levels of Zn up to 4% (dry weight) and preserved the isotopic signatures of electroplating wastes. However, there is evidence that biogeochemical processes triggered by hydrodynamics, bioturbation or rhizosphere processes slightly changed the isotopic signatures in some layers. Calculations based in this mixing model quantified contributions of the major anthropogenic source of Zn, ranging from negligible values in the pre-industrial period to nearly 80% during periods of electroplating activities between the 60’s and 90’s. The Zn isotope systematics of mollusc bivalves were not associated to mixing process of sources. Instead, these bioisotopic signature seems related to different routes of bioaccumulation, i.e. uptake via dissolved or particulate phase. It is hypothesized that in the zone heavily impacted zone by old electroplating wastes, the bivalves incorporate the high levels of Zn in the dissolved phase though the bivalve gills, while outside this zone, these organisms incorporate the labile Zn bound to particulate matter during the gut digestion. Zinc isotopic signatures of leaves did not also allowed identification of sources due to the significant isotopic fractionation during Zn uptake by the roots. Leaves of sites highly contaminated presented different Zn isotopic patterns of those of low or no contaminated sites. These patterns may be associated to activation of tolerance mechanisms of mangrove’s trees where Zn reach toxic levels. To conclude, Zn isotopes compositions of abiotic samples such as sediments are effective to detect biogeochemical changes triggered by anthropogenic activities and, therefore, can be useful to support prevention, monitoring and prediction of risks in coastal sites impacted by metal contamination. Biological samples of mollusc bivalves and leaves of mangrove’s trees are not suitable to sources tracing, but the distinct isotopic patterns of Zn found for those samples from sites highly contaminated are promising as biomarkers of metabolic pathways and physiological effects associated to metal contamination. Future investigations are required to constrain the relationships among Zn speciation, uptake mechanisms and the Zn bioisotopic of leaves and bivalve tissues.Les zones côtières du monde entier sont sous fort pression de contamination anthropique comme conséquence de la concentration de la plupart de la population mondiale et des activités économiques le long des côtes et des estuaires. La menace de contaminant sur les écosystèmes rend primordial le développement d’outils capable de détecter les modifications biogéochimiques en vue d’aider dans la prévention, la gestion, et la prédiction de risques dans les études environnementales. Dans ce but, cette thèse étudie la biogéochimie des isotopes du Zinc (Zn) en vue de développer un outil capable de tracer les sources naturelles et anthropiques, d’identifier les processus biogéochimiques et de permettre à la biosurveillance de la contamination par les métaux dans les zones côtières et les mangroves. A cette fin, les compositions isotopiques du Zn ont été déterminées à plusieurs échantillons naturels prélevés dans la baie de Sepetiba (au sud-est du Brésil), un estuaire lagunaire affecté par une côte industrialisée située près de Rio de Janeiro. Cette baie constitue un laboratoire naturel idéal pour valider le système isotopique du Zn. En effet, cette zone héberge des écosystèmes d’intérêt commercial et écologique –estuaire, mangrove, estran- menacés par la contamination d’une ancienne activité de galvanoplastie, et d’autres sources diffuses. Les échantillons collectés comprennent des carottes de sédiments, des sédiments de la superficie des mangroves, des matériaux particulaires en suspension (SPM), des feuilles provenant d’arbres de mangrove, des tissus de mollusques bivalves (huîtres et moules) et des roches. Minéraux de dépôt de Vazante (Brésil) ont été collecté pour representé matière première utilisée par l’industrie de la galvanoplastie. Tout d’abord, un travail initial de laboratoire a établi une méthode exacte et précise pour les déterminations isotopiques Zn en échantillons naturelles par spectrométrie de masse avec plasma couplé par induction et multicollecteur (MC-ICP-MS). Des analyses spatiales et temporelles des compositions isotopiques du Zn des échantillons de sédiments et de roches s’ajustent bien à un modèle de mélange entre trois principales extrémités : i) les matériaux continentaux charriés par les rivières ; ii) les sources marines ; et iii) une source anthropique majeure associée aux anciens déchets de galvanoplastie jetés dans la baie. Les carottes de sédiment collectées dans la vasière ont montré une haute corrélation entre la composition isotopique du Zn et le facteur d’enrichissement du Zn. Ceci suggère : i) une bonne préservation du registre isotopique des sources naturelle et anthropique, ii) l’absence de fractionnement isotopique significatif durant le transport de sédiments ou durant les réactions diagénétiques pos-dépositions dans le système estuarien. La carotte de sédiments collectée dans la mangrove, située dans la zone impactée par l’ancienne activité galvanoplastique a présenté des concentrations de Zn au-dessus de 4% (pèse sec) et a préservé les signatures isotopiques des déchets de la galvanoplastie. Cependant, il est évident que les processus biogéochimiques déclenchés par les processus hydrodynamiques, par la bioturbation, et par la rhizosphère peuvent altérer les signatures isotopiques de certaines couches de sédiment. Les calculs basés sur ce modèle de mélange quantifient les contributions de la principale source anthropique variant de valeurs négligeables en périodes préindustrielles jusqu’aux 80% pendant les périodes d’activités de galvanoplastie entre les années 60 and 90. La systémique des isotopes du Zn des mollusques bivalves n’est pas associée au processus de mélange des sources. Au lieu de cela, ces signatures bioisotopiques semblent liées à différentes routes de bioaccumulations, i.e. par l’incorporation de phase dissoute ou de particules. L’hypothèse est que, dans les zones sévèrement impactées par les anciens rejets de galvanoplastie, les bivalves incorporent les hautes concentrations du Zn sous forme dissoute via les branchies. Cependant, hors de cette zone, ces organismes incorporent via la digestion le Zn labile. Les signatures isotopiques du Zn des feuilles également n’ont pas permis l’identification des sources en raison du fractionnement isotopique significatif au cours de l’incorporation du Zn par les racines. Les feuilles des sites hautement contaminé ont montré des standards isotopiques du Zn diffèrent des feuilles des sites peu ou non contaminé. Ces standards peuvent être associés à l’activation de mécanismes de tolérance par les arbres de la mangrove où le Zn atteint des niveaux toxiques. En conclusion, les compositions isotopiques du Zn des échantillons abiotiques, comme les sédiments, permettent de détecter les changements biogéochimiques déclenchés par des activités anthropiques. Ainsi, elles sont utiles pour donner des supports á la prévention, á la gestion, et á la prédiction de risques dans les zones impactées par la contamination métallique. Échantillons biologiques de mollusques bivalves et de feuilles provenant d’arbres de mangroves ne sont pas appropriés pour tracer les origines du Zn. Cependant, les distinctes compositions isotopiques du Zn des échantillons collecté aux sites hautement contaminé sont prometteurs pour l’application de ces isotopes comme marqueurs biologiques de réactions métaboliques et de réponse physiologiques. Toutefois, il faut plus de recherches afin de comprendre la relation entre la speciation du Zn, mécanismes de d’incorporation et les signatures bioisotopiques de cet élément dans les tissus de bivalves et feuilles

The isotopic composition of Zn in natural materials

This work represents the most recent development of Zn isotopic measurements, and the first identification of Zn isotopic fractionation in natural materials using Thermal Ionisation Mass Spectrometry (TIMS). The procedures developed in this research systematically evaluates and solves several critical analytical issues involved in TIMS Zn isotopic measurements such as, reducing the size of sample needed to perform an accurate and precise measurement, minimizing the effect of interferences on the Zn fractionation, reducing the blank associated with the analyses, dissolution and purification of different natural samples, and the generally ignored issue of the effect of the ion exchange chemistry (Zn separation) to the fractionation of Zn. These procedures have allowed sub-permil fractionations in the isotopic composition of Zn to be revealed in small Zn sample (1µg), and the determination of low level (ng) elemental abundance of Zn in samples to be measured accurately by the means of isotope dilution mass spectrometry IDMS. This thesis uses the rigorous double spike technique to measure fractionation, relative to the internationally proposed absolute Zn isotopic reference material (δ zero), based on a high purity Alfa Aesar 10759, now available to the international isotope community. All the isotopic measurements in natural materials were performed on bulk samples purified by ion exchange chemistry.The isotopic composition of the Zn minerals and igneous rocks agreed with that of the absolute reference material, which makes it possible to consider this reference material as being representative of “bulk Earth” Zn. Significant and consistent fractionation of ~+0.3 ‰ per amu were found in 5 sediments from a range of localities. The consistency of this is attributed to conveyor type oceanic circulations effects. The results from the two metamorphic samples indicate that the fractionation of Zn in these rocks is the same as found in igneous rocks but are different from the Zn found in sedimentary rocks. This supports the widely held assumption that high temperature and pressure processes do not fractionate the isotopic composition of chalcophile elements, such as has been found for Cd. Clay sample TILL-3 appears to exhibit a consistently slightly positive Zn fractionation of +0.12 ± 0.10 ‰ amu-1, although inside the uncertainties of both igneous and sedimentary rocks, which is not surprising since Till is thought to be a formed from a range of mixed glacial sediments The isotopic composition of Zn was measured in two plants and one animal sample. The fractionation of (-0.088 ± 0.070 ‰ amu-1) of Zn in the Rice (a C3 type plant material) sample suggested that Zn may be used to study Zn systematics in plants. The result obtained for MURST-Iss-A2 (Antarctic Krill) was +0.21 ± 0.11 ‰ amu-1 relative to the laboratory standard which is similar to the average Zn fractionation results of +0.281 ± 0.083 ‰ amu-1 obtained for marine sediments.In this work, the isotopic composition of Zn was measured in five stone and two iron meteorites. The range of Zn fractionation in stone meteorites was between -0.287 ± 0.098 and + 0.38 ± 0.16 ‰ amu-1, and was consistent with previous work, although more measurements would be needed to generalize this to all stone meteorites. In iron meteorites; Canyon Diablo was found to have the greatest fractionation of +1.11 ± 0.11 ‰ amu-1 relative to the laboratory standard. Of all the meteorites studied, Redfields clearly showed an anomalous isotopic composition indicating that this meteorite possesses a significantly different Zn isotopic composition compared to all of the other natural materials measured. Using 64Zn as a reference isotope, significant differences relative to the laboratory standard were found of +5.6 ± 0.4‰, +4.4 ± 3.6 ‰, and +21.0± 0.9 ‰ and +27.4 ± 18.8 ‰ on 66Zn and 67Zn, 68Zn and 70Zn respectively. These significant “Redfields anomalies” can be interpreted in a number of ways in relation to their nucleosynthetic production. Whether Redfields is a primitive type of iron meteorite or not, the Redfields anomaly strongly suggests wide spread isotopic heterogeneity of at least one part of the Solar System and does not support the suggestion that “Zn was derived from an initially single homogeneous reservoir in the early Solar System”. A pilot study to determine the concentration and the isotopic composition of Zn in River and tap water was performed.The concentration of Zn in River water averaged 6.9 ± 0.8 ngg-1, while for tap water it ranged from 13.1 ngg-1 to 5.2 μgg-1. River water was fractionated by -1.09 ± 0.70 ‰ amu-1, while restrained tap water yielded the maximum fractionation of -6.39 ± 0.62 ‰ amu-1 relative to the laboratory standard. The Zn fractionation of tap water is much larger than all other natural samples, although the uncertainty is also significantly greater due to the use of the less precise Daly detector used for these preliminary experimental measurements. The fractionation of Zn in seven ultra pure Zn standard materials was measured relative to the laboratory standard and found to range from -5.11 ± 0.36 ‰ amu-1 for AE 10760 to +0.12 ± 0.16 ‰ amu-1 for Zn IRMM 10440. There appears to be some evidence for a relationship between Zn fractionation and its purity. As well as natural materials, the fractionation of Zn was measured in a number of processed materials. None of these results or those obtained for natural materials impact on the currently IUPAC accepted value for the atomic weight of Zn. Along with fractionation determinations, the concentration of Zn was also measured by Isotope Dilution Mass Spectrometry in all of the samples. The concentration of Zn in five stony meteorites ranged from 26 ± 13 to 302 ± 14 μgg-1 for Plainview and Orgueil respectively. For ordinary Chondrites, the concentration of Zn in the three samples analysed ranged from 26 ± 13 to 64 ± 34 μgg-1 for Plainview and Brownfield 1937 respectively.The concentration of Zn was measured in two metamorphic rocks standard materials; the maximum concentration was 101.5 ± 1.7 µgg-1 in SDC-1. The concentration of Zn present in plant samples studied in this research was 22.15 ± 0.42, 14.62 ± 0.27 µgg-1 for Rice IMEP-19 and Sargasso NIES-Number 9 respectively which is within the normal range of Zn concentrations. Except for meteorites, the final uncertainties consistently cover the ranges of individual concentration measurements and indicate the homogeneity of the samples, including samples from different bottles where available. The final fractional uncertainties obtained for SRMs were all less than 2.8 %, demonstrating the high level of precision possible using IDMS