Dissertations / Theses on the topic 'Trace metal concentrations'

Samples were taken from 72 high-rise apartment suites (6 suites in 12 individual high-rise towers) and 60 single-family houses located within the Greater Vancouver Regional District. The influence of the following factors on trace metal concentrations in 1-L first-flush drinking water samples and running hot water samples was investigated: building height, location, plumbing age, type of plumbing and type of building. Results of this survey show that with the exception of building height, all factors had a correlation with one or more of the trace metals investigated. The trace metals examined were lead, copper, iron and zinc. Lead was influenced primarily by building type, copper by plumbing age and type of plumbing and iron by location. Elevated lead levels were associated with high-rise samples. New copper plumbing systems resulted in high copper levels. Highest iron levels in the drinking water were measured in the East location. Zinc did not show a distinct correlation with any of the factors investigated. Brass faucets were the primary source of zinc in tap water. They also contributed substantially to the lead detected in the 1-L first-flush sample. Metal concentrations measured in high-rise and house samples were compared with U.S. Environmental Protection Agency's (USEPA) maximum contaminant levels (MCLs) and the proposed no-action level for lead1. In high-rise samples, the 0.01 mg/L "no-action" proposed for lead was exceeded in 43% of the samples and 62% of the samples exceeded the current 1.0 mg/L MCL standard for copper. In single-family house samples, these values were 1 Compliance with the proposed 0.01 mg/L no action limit for lead is based on a sample average. Individual samples may exceed this value and still be in compliance. 47% and 73%, respectively. The average lead concentration for all high-rise samples was 0.020 mg/L and 0.013 mg/L for house samples. Regulatory levels stated above would still be exceeded in 6% of the cases for lead and 9% of the cases for copper, even after prolonged flushing of the tap in a high-rise building. In all cases associated with single-family houses, flushing the cold water tap for 5 minutes was successful in achieving compliance levels.
Applied Science, Faculty of
Civil Engineering, Department of
Graduate

Sediments from 21 Oregon lakes were analyzed for seven metals (Fe, Mn, Zn, Cu, Co, Ni, V) in three forms (exchangeable, organic+sulfides, and oxyhydroxides+ oxides+ carbonates) using a sequential fractionation procedure. The summer epilimnetic filterable concentration of an eighth (Mo) was also determined. Sedimentary diatom remains and summer phytoplankton populations of the lakes were correlated with the 22 metal parameters and with conservative water chemistry parameters, estimators of lake productivity, and watershed geology. Both the sedimentary metals and the two populations of primary producers correlated best with the ecoregions of Omernik and Gallant (1986). A number of species possessed correlations with specific trace metal extractions or ratios of those extractions. Bloom-forming Anabaenas strongly correlated with sedimentary organic and filterable epilimnetic nickel. Possible Ni limitation of this group was observed in one Cascade lake (Lava). The ratio of organic nickel to cobalt appeared to control the abundance of several sedimentary diatoms. Organic vanadium strongly correlated with a number of diatoms, particularly in the genera, Cyclotella and Fragilaria. Possible V pollution was observed in one lake (Woahink), and frustule remains of C. stelligera significantly increased with increasing total sedimentary V concentrations there. Zinc was the trace metal most frequently found to apparently limit diatom growth. Diatoms may have developed three different responses to Zn limitation; the three groups have been labelled affinity-, velocity-, and (possibly) storage- specialists following Sommer (1985). Possible Zn pollution was observed in two lakes (Oswego and Clear). Phytoplankton and sedimentary diatoms weakly correlated with sedimentary iron by comparison to Ni, V, or Zn. Few strong relationships were observed with manganese, copper, or cobalt. No statistically significant correlations were found with molybdenum, and few correlations between a conservative chemical parameter and a species of phytoplankton were found. There was poor correlation between trace metal concentrations and lake productivity, despite frequently observed correlations between individual species and particular trace metal fractions. These findings suggest that variations in absolute trace metal concentrations, and/or ratios, may be important factors for controlling species distribution, but have relatively little influence upon lake primary productivity or standing stocks.

The concentrations of trace metals: cadmium, copper, nickel, lead and mercury, in addition to aluminium, iron and manganese were determined in the sediments and pore water (except aluminium) of the Forth estuary. Organic matter (as loss on ignition), total organic carbon (TOe), total organic nitrogen (TON), particle size and redox potential were also determined in the sediments. In addition, chloride, sulphate, conductivity, alkalinity, pH, dissolved organic carbon, phosphate and nitrate were determined in the sediments pore water. Trace metals in the pore water were determined using a modified preconcentration technique and measurements were carried out by graphite furnace. Mercury was measured using the p.s.a mercury specific fluorescence detector. organic matter (TOC & TON) in the sediments were measured using CHNS/O analyzer. Samples were collected at seasonal intervals for a period of 18 months on board the survey vessel "Forth Ranger". Six stations were selected to represent upper, middle and lower estuary. Sediment cores collected at each station were subjected to centrifugation under nitrogen gas atmosphere to separate the pore water after being sectioned at 2.5 cm intervals for a depth of 10 centimetres. Concentrations of trace metals in the Forth estuary varied from station to station and from one season to another. Mean concentrations for sediments were as follows (mg\kg): lead, 56.9; cadmium, 0.22; copper, 38.9; nickel, 33.7 and mercury, 1.86. For pore water, the mean concentraxxi tions (Jlg\l) were as follows: lead, 3.14; cadmium, 1.86; copper, 31.9; nickel, 24.7 and mercury, 0.075. Measurements of sulphates, nitrates, phosphate, conductivity and dissolved organic carbon were used to examine the processes controlling their distributions in the pore water. The results indicated that the distributions of nutrients (phosphate and nitrate) in the upper 10 cm seemed to be controlled by macro-infaunal irrigation activities and their values varied according to the overlying water conditions. The distributions of trace metals in the sediments were found to be controlled by particle size and organic matter both spatially and temporally. Vertical distribution of trace metals in the pore water were found to be controlled by redox potential variations especially for iron and manganese. Concentrations of trace metals (Pb, Hg, Ni, Cd and CU) in the pore water were found to be higher than that in the overlying water. Enrichment factors were limited to 10-50 fold increase. Lead and mercury were 10 fold higher while 50 fold higher were found for nickel, copper and cadmium. Benthic flux calculations showed a significant flux of trace metals both in the summer and winter. However, flux of copper, nickel and lead tended to increase in the summer. Spatially, the lower estuary showed a higher flux of trace metals than the upper and middle reaches of the estuary.

This study examines the occurrence, distribution and storage of selenium in seagrass communities of Lake Macquarie, which is a heavily industrialised area of NSW, where notably high trace metal concentrations have been reported previously. Initially a suite of organisms was collected from a seagrass bed (Zostera capricornia) in the southeastern section of the lake to investigate the bioaccumulation and biomagnification of selenium. All organisms contained selenium, with sediment-dwelling organisms containing the highest Se concentrations. No consistent pattern of significant Se-metal correlations with Cu, Zn and Cd was found. Biomagnification of Se was evident, as concentrations increased from sediments and water to flora (algae and seagrass) to bivalves to Crustacea. However, this trend was not continued to the higher trophic groups of invertebrate predators and teleost fish. The bivalve Anadara trapezia was further studied. Intrinsic and extrinsic factors affecting the accumulation of Se were examined. Gender and mass were assessed in a single day study, followed by a temporal investigation of the effect of gender, reproductive cycle, temperature and salinity on Se accumulation. Gender had no effect on the accumulation of Se in A. trapezia. Se was present in all tissues (adductor, blood, foot, gills, intestine and mantle) and not immobilised or stored in a specific tissue, indicating that it plays a structural role in the tissues of A. trapezia. Se burden increased relative to size (shell length and dry mass) suggesting that Se is metabolically controlled within the organism. Se concentrations were found to fluctuate temporally because of: food availability in response to water temperatures; the reproductive cycle; and associated metabolic activities responding to temperature changes and food availability. Subcellular selenium associations in A. trapezia were examined to assist in the understanding of the fate of Se in marine tissues. Most of the Se was associated with proteins, suggesting that Se has a metabolic role in this marine organism. Proteins are intrinsically associated with the lipid bilayer of the cell membranes. A number of proteins (94, 85, 43, 36.5, 30, 23.4, 17.4 and 15 kDa) were separated by SDS PAGE from ethanol fractions. Determination of the Se concentration within individual proteins was not possible because the ratio of Se to protein was too low for further analysis. These findings indicated that Se plays a metabolic role in the tissues of the marine organism A. trapezia. The biochemical regulatory mechanism responsible for maintaining Se concentrations within the tissues is currently unknown.

Thesis (PhD (Soil Science))--University of Stellenbosch, 2007.
Trace elements occur naturally in soils, usually at low concentrations (<0.1% or <1000 mg kg-1 of the earth’s crust), as a result of weathering and pedogenic processes acting on the rock fragments from which soil develops (parent material). Since about 98% of human food is produced on land, soil is the primary source supplying these elements to the food chain. Although cases of trace element deficiency and toxicity have been documented in many parts of South Africa, no comprehensive description of trace element concentration has yet been attempted for South Africa as a whole. The Natural Resources Land Type mapping project, initiated in the mid-1970s, has provided a collection of samples (approximately 4500) from soil profiles selected to represent the main soil forms in each land type and therefore to provide representative coverage of most of the soils of South Africa. These archived samples have now been analysed for a spectrum of trace elements, in terms of both available and total concentrations as well as other soil properties. Although detailed information is available on a wide range of trace metals, the seven trace metals considered to be of most interest in a South African context due to natural geological occurrences were selected for this study, including Cd, Co, Cr, Cu, Pb, Ni and Zn. This data was used to: • determine baseline concentrations in SA soils; • determining threshold values for South African agricultural soils receiving sewage sludge at agronomic rates; • determining the influence of certain soil properties on the baseline concentrations of these trace elements in SA soils; and • development of a bioavailable trace element distribution map for SA. The range, the mean and standard deviation (both arithmetic and geometric), and the median were used to summarize the data statistically. The baseline concentration range was calculated using the quotient and product of the geometric mean and the square of the geometric standard deviation, including data below the instrument detection limit. The upper limit of the baseline concentration range was set at the 0.975 percentile value of the population in order to minimize the influence of contamination and the lower limit at the 0.025 percentile value to minimize problems that might be associated with analytical uncertainty near the lower limit of detection. The quantile regression statistical approach was followed to illustrate the relationship between soil properties and trace element concentrations in soils. The soil properties that showed the strongest relation were CEC, clay content, pH (H2O) and S value (base status). The soils were then divided into different classes according to these soil properties and baseline concentrations were derived for the different classes. Soils with low clay contents have lower trace element concentrations than soils with higher clay contents, soils with low or high pH levels have lower trace element contents than soils with intermediate pH values and mesotrophic soils have higher trace element concentrations than dystrophic soils. This information is useful for the compilation of trace element distribution maps for South Africa where different soil forms and series/families could be classified into different classes to determine areas of potential deficiencies as well as toxicities. South Africa, with its diverse geology, has areas of both trace element toxicities and deficiencies and for decision-making purposes it is necessary to identify these areas. Mapping of trace element levels based on soil samples would provide valuable information, which cannot be obtained from geological or geographical maps. Statistical analyses of the data (clay %, base status, pH (H2O) and NH4EDTA extractable trace element concentrations) indicated that soils could be divided into five trace element classes based on their clay content, pH and base status (dystrophic, mesotrophic and eutrophic). The soil series according to the binomial soil classification system for South Africa were then divided into these different classes. The geometric means for each clay class were determined and the baseline concentration range for each class was calculated. The land type maps were used as basis for the distribution maps. A general trace element distribution map for South Africa was derived from this data as well as Cu and Zn distribution maps. A random selection of 500 soil samples across the country was used to verify the accuracy of the distribution map. The general trace element distribution map indicate, with a confidence level between 89 and 96%, where the potentially available trace element content of South African soils are low (deficient) too moderately high, excluding rocky areas and areas with limited soil. The Cu and Zn maps indicate the distribution and expected baseline concentrations of these specific elements in South African soils. The same methodology could be applied to derive risk maps for all the individual trace elements to indicate the distribution and expected baseline concentrations of the elements in South Africa. This presentation of baseline concentrations, reflecting likely natural ranges in South African soils, is the first quantitative report on the spatial extent and intensity of Zn, Cu and Co deficiency in South African soils. The proposal of new threshold values for trace elements in agricultural soils will be valuable in setting more realistic norms for environmental contamination that accommodate the geochemical peculiarities of the region, one example being rather high Cr and Ni concentrations with low bio-availability. This information should be of value not only in environmental pollution studies but also in health, agriculture, forestry and wildlife management. The following recommendations are made: • The baseline concentrations could be used to determine site specific threshold values based on soil properties and soil type. Soils with lower pH, clay content and CEC would require more protection than soils with high pH, clay content and CEC and therefore the threshold levels for these soils should be lower. • Although the distribution maps can be used to indicate broad areas of trace element deficiencies and toxicities, more detailed investigations are recommended for areas where problems are experienced. The same methodology could be applied on smaller scale to increase the value of the map and to add more value on a regional scale. The maps could be used for regional soil quality assessment especially in areas where trace element deficiencies or toxicities could result in negative effects on plants and animals.

This study combined concentration-discharge analyses (filtration at 0.45 m), cascade filtrations (at 1.2, 0.4, and 0.025 m) and asymmetrical flow field flow fractionation (AF4) to probe the influence of colloidal carriers (dissolved organic matter and inorganic nanoparticles) on observed concentration-discharge relationships for trace metals in a 155 ha forested catchment of the Santa Catalina Mountains Critical Zone Observatory (SCM CZO), Arizona. Many major elements (Na, Mg, Si, K, Ca) show no colloidal influence, and concentration-discharge relationships for these species are explained by previous work. However, the majority of trace metals (Al, Ti, V, Mn, Fe, Cu, Y, REE, U) show at least some influence of colloids on chemistry when filtered at the standard 0.45 m cutoff. Concentration-discharge slopes of trace metals with modest colloidal influence are shallow (approximate to 0.3) similar to that measured for dissolved organic carbon (DOC, 0.24), whereas elements with greater colloidal influence have steeper concentration-discharge slopes approaching that of Al (0.76), the element with the largest colloidal influence in this study (on average 68%). These findings are further supported by AF4 measurements that show distinct and resolvable pools of low hydrodynamic diameter DOC-sized material coexistent with larger diameter inorganic colloids, and the ratio of these carriers changes systematically with discharge because the DOC pool has a concentration-discharge relationship with shallower slope than the inorganic colloidal pool. Together these data sets illustrate that positive concentration-discharge slopes of trace metals in stream waters may be explained as the relative partitioning of trace metals between DOC and inorganic colloids, with contributions of the latter likely increasing as a result of increased prevalence of macropore flow.

Concentrations of Fe, Al, Mn and Zn were measured monthly from April to October at 24 rural riverine sites in Ontario and Quebec. Empirical models were developed predicting riverine metal concentrations from a small set of within-stream and catchment variables. Models explained a significant proportion of the variation in Fe (85%), Al (90%), Mn (57%) and Zn (37%). Simple models predicting annual catchment exports of metals from average riverine suspended particulate concentrations and runoff were also developed. These models explained most of the variation in annual exports of Fe (94%), Al (92%), Mn (62%) and Zn (75%) from the 24 catchments.
Models such as these can be used both to estimate catchment exports of metals to lakes, and to estimate riverine metal concentrations without requiring chemical analyses. The models also serve to distinguish background levels from those indicating metal contamination, and will, therefore, be useful in design of water quality guidelines.

This work represents a first look at the general spatial distribution of trace metals and the inorganic carbon system in the surface waters of Tampa Bay. Tampa Bay's chemical environment bears many influences ranging from hydrological and geological to anthropogenic and meteorological. A large y-shaped estuary on the west-central side of the Florida Peninsula, Tampa Bay extends over 400 square miles and has a 2200 square mile watershed that includes extensive swamps, scrub, agricultural lands and densely urbanized areas. Reaching 37 miles from the northernmost point of Old Tampa Bay to the mouth of the estuary near the Sunshine Skyway Bridge, it is home to the largest port in Florida, and overall places 17th in the nation for tonnage. In addition to its ports, Tampa Bay supports the requirements of a broad range of industries including: ship building and repair, power generation, wastewater processing, development, and recreational and commercial fishing. The region experiences high rainfall during the summer and much reduced rainfall during the remaining portions of the year. The bay has a broad gradient of mixing intensities, with residence times ranging from 100+ days in Old Tampa Bay to less than 20 days at the mouth. Seventy-one percent of Tampa Bay's freshwater input is delivered by four primary rivers: the Hillsborough, Alafia, Manatee and Little Manatee; and the region is strongly influenced by spring outflow from the Floridan Aquifer. The largest river, the Hillsborough, spans 54 miles from the Green Swamp to its mouth in Hillsborough Bay. Samples were collected over a two-week period in January of 2013 along 13 sites on the Hillsborough River and 26 stations in Tampa Bay. Metal concentration analyses were conducted on twelve elements using inductively coupled plasma mass spectrometry (ICP-MS). These twelve elements included sodium, lithium, magnesium, calcium, strontium, barium, vanadium, molybdenum, manganese, nickel, antimony, and uranium. Within Tampa Bay, sodium, lithium, and magnesium exhibited strongly conservative behavior (showing simple two-end-member mixing). Calcium, strontium, molybdenum, and uranium show quasi-conservative behavior, with localized deviations from simple mixing of fresh water and seawater end members. The remaining elements showed variable behavior driven by solubility, redox reactions, and/or unique localized inputs based on local geology. Comparisons of baywater calcium concentrations and the concentrations of lithium, magnesium, strontium and barium revealed simple relationships that are promising for use in interpretations of otolith chemistry of teleosts and some agnatha (Campana, 1999; Carlström, 1963). Samples were collected from both the river and the bay for CO2 system analyses. Spectrophometric pH measurements were obtained using purified m-Cresol Purple (mCP) and the procedures of Liu et al. (2011). Dissolved inorganic carbon (DIC) was processed according to CDIAC's Guide to Best Practices, SOP:2 (Dickson, Sabine, & Christian, 2007). Total alkalinity samples were processed using the spectrophotometric procedures of Yao and Byrne (1998). Dissolved inorganic carbon in the bay ranged between 3500 µMol/L and 2250 µMol/L and, in the Hillsborough River, peaked at 3700 µMol/L just below the Green Swamp. A comparison of measured total alkalinity and calculated alkalinity (obtained using pH and DIC and CO2sys software) demonstrated the presence of substantial organic base concentrations within the bay.

Les lacs jouent un rôle particulier dans le cycle de l’eau dans les bassins versants urbains. La stratification thermique et le temps de séjour de l’eau élevé favorisent le développement phytoplanctonique. La plupart des métaux sont naturellement présents dans l’environnement à l’état de traces. Ils sont essentiels pour les organismes vivants. Néanmoins, certains métaux sont connus pour leurs effets toxiques sur les animaux et les humains. La concentration totale des métaux ne reflète pas leur toxicité. Elle dépend de leurs propriétés et de leur spéciation (fractions particulaires, dissoutes: labiles ou biodisponibles et inertes). Dans les systèmes aquatiques, les métaux peuvent être absorbés par des ligands organiques ou minéraux. Leur capacité à se complexer avec la matière organique dissoute (MOD), particulièrement les substances humiques, a été largement étudiée. Dans les lacs, le développement phytoplanctonique peut produire de la MOD non-humique, connue pour sa capacité complexante des métaux. Pourtant, peu de recherche sur la spéciation des métaux dans la colonne d’eau des lacs urbains a été réalisée jusqu’à présent.Les objectifs principaux de cette thèse sont (1) d’obtenir une base de données fiables des concentrations en métaux traces dans la colonne d’eau de lacs urbains représentatifs; (2) d’évaluer leur biodisponibilité via une technique de spéciation adéquate ; (3) d’analyser leur évolution saisonnière et spatiale et leur spéciation; (4) d’étudier l’impact des variables environnementales, en particulier de la MOD autochtone sur leur biodisponibilité; (5) de lier la concentration des métaux au mode d’occupation du sol du bassin versant.Notre méthodologie est basée sur un suivi in-situ des lacs en complément d’analyses spécifiques en laboratoire. L’étude a été conduite sur trois sites: le lac de Créteil (France), le lac de Pampulha (Brésil) et 49 lacs péri-urbains (Ile de France). Sur le lac de Créteil, plusieurs dispositifs de mesure en continu nous ont fourni une partie de la base de données limnologiques. Dans le bassin versant du lac de Pampulha, la pression anthropique est très importante. Le climat et le régime hydrologique des 2 lacs sont très différents. Les 49 lacs de la région d’Ile de France ont été échantillonnés une fois pendant trois étés successifs (2011-2013). Ces lacs nous ont fourni une base de données synoptique, représentative de la contamination métallique à l’échelle d’une région fortement anthropisée.Afin d’expliquer le rôle des variables environnementales sur la concentration métallique, le modèle Random Forest a été appliqué sur les bases de données du lac de Pampulha et des 49 lacs urbains avec 2 objectifs spécifiques: (1) dans le lac de Pampulha, comprendre le rôle des variables environnementales sur la fraction labile des métaux traces, potentiellement biodisponible et (2) dans les 49 lacs, comprendre la relation des variables environnementales, particulièrement au niveau du bassin versant, sur la concentration dissoute des métaux. L’analyse des relations entre métaux et variables environnementales constitue l’un des principaux résultats de cette thèse. Dans le lac de Pampulha, environ 80% de la variance du cobalt labile est expliqué par des variables limnologiques: Chla, O2, pH et P total. Pour les autres métaux, le modèle n’a pas réussi à expliquer plus de 50 % de la relation entre fraction labile et variables limnologiques. Dans les 49 lacs, le modèle Random Forest a donné un bon résultat pour le cobalt (60% de la variance expliquée) et un très bon résultat pour le nickel (86% de la variance expliquée). Pour Ni les variables explicatives sont liées au mode d’occupation du sol : « Activités » (Equipements pour l’eau et l’assainissement, entrepôts logistiques, bureaux…) et « Décharge ». Ce résultat est en accord avec le cas du lac de Créteil où la concentration en Ni dissous est très élevée et où les catégories d’occupation du sol « Activités » et « Décharges » sont dominantes
Lakes have a particular influence on the water cycle in urban catchments. Thermal stratification and a longer water residence time in the lake boost the phytoplankton production. Most metals are naturally found in the environment in trace amounts. Trace metals are essential to growth and reproduction of organisms. However, some are also well known for their toxic effects on animals and humans. Total metal concentrations do not reflect their ecotoxicity that depends on their properties and speciation (particulate, dissolved: labile or bioavailable and inert fractions). Trace metals can be adsorbed to various components in aquatic systems including inorganic and organic ligands. The ability of metal binding to dissolved organic matter (DOM), in particular humic substances, has been largely studied. In urban lakes, the phytoplankton development can produce autochthonous DOM, non humic substances that can have the ability of metal binding.. But there are few studies about trace metal speciation in lake water column.The main objectives of this thesis are (1) to obtain a consistent database of trace metal concentrations in the water column of representative urban lakes; (2) to access their bioavailability through an adapted speciation technique; (3) to analyze the seasonal and spatial evolution of the metals and their speciation; (4) to study the potential impact of environmental variables, particularly of dissolved organic matter related to phytoplankton production on metal bioavailability and (5) to link the metal concentrations to the land use in the lake watershed.Our methodology is based on a dense field survey of the water bodies in addition to specific laboratory analysis. The research has been conducted on three study sites: Lake Créteil (France), Lake Pampulha (Brazil) and a panel of 49 peri-urban lakes (Ile de France). Lake Créteil is an urban lake impacted by anthropogenic pollution. It benefits of a large number of monitoring equipment, which allowed us to collect a part of the data set. In Lake Pampulha catchment, the anthropogenic pressure is high. Lake Pampulha has to face with many pollution point and non-point sources. The climate and limnological characteristics of the lakes are also very different. The panel of 49 lakes of Ile de France was sampled once during three successive summers (2011-2013); they provided us with a synoptic, representative data set of the regional metal contamination in a densely anthropized region.In order to explain the role of the environmental variables on the metal concentrations, we applied the Random Forest model on the Lake Pampulha dataset and on the 49 urban lake dataset with 2 specific objectives: (1) in Lake Pampulha, understanding the role of environmental variables on the trace metal labile concentration, considered as potentially bioavailable and (2) in the 49 lakes, understanding the relationship of the environmental variables, more particularly the watershed variables, on the dissolved metal concentrations. The analysis of the relationships between the trace metal speciation and the environmental variables provided the following key results of this thesis.In Lake Pampulha, around 80% of the variance of the labile cobalt is explained by some limnological variables: Chl a, O2, pH, and total phosphorus. For the other metals, the RF model did not succeed in explaining more than 50% of the relationships between the metals and the limnological variables.In the 49 urban lakes in Ile de France, the RF model gave a good result for Co (66% of explained variance) and very satisfying for Ni (86% of explained variance). For Ni, the best explanatory variables are landuse variables such as “activities” (facilities for water, sanitation and energy, logistical warehouses, shops, office…) and “landfill”. This result fits with Lake Creteil where dissolved Ni concentration is particularly high and where the “activities” and “landfill” landuse categories are the highest

La réutilisation des eaux usées traitées pour l’irrigation est globalement acceptée et pratiquée pour faire face à la pénurie d'eau et économiser les ressources de haute qualité. Bien que cette pratique présente des avantages indéniables et contribue à un usage plus durable de l'eau douce, elle n’est pas exempt de problèmes liés à l'impact potentiel sur la qualité des sols récepteurs et sur les cultures de micropolluants contenus dans l'eau réutilisée. Parmi ces polluants, les métaux lourds (ML) en concentrations traces jouent un rôle primordial en raison de leur présence systématique dans l'eau utilisée et de leur persistance une fois libéré dans l'environnement. Le devenir des ML dans les sols peut difficilement être prédit parce que les mécanismes de mobilité à travers les sols sont extrêmement variés et liés à des phénomènes simultanés et très complexes impliquant différents équilibres chimiques. Les ML, comme beaucoup d'autres contaminants, ne sont pas seulement partagé entre la phase immobile (le sol) et les phases mobiles présentes dans l'eau. En effet, les colloïdes et les nanoparticules agissent comme une troisième phase mobile, avec leurs propres propriétés rhéologiques et des vitesses de migrations qui leur sont propres. Ce dernier aspect a été l'un des principaux objectifs d’étude de la thèse. Plusieurs essais expérimentaux ont été menés en irriguant un sol standard selon l'Organisation de coopération et de développement économiques (OCDE) avec une eau usés traités réel et / ou synthétiques, contenant des ML en concentrations traces. Pour chaque test, un sol spécifique (avec différentes teneurs en matière organique) et des eaux usées traitées de composition différente (avec différentes concentrations en métaux traces, de salinité, de la teneur en matière organique pour les eaux usées synthétiques, ou des eaux usées traitées réelles) ont été choisi afin d'évaluer les effets des conditions différentes sur le devenir global des ML. L'augmentation de la matière organique du sol de 2,5 à 10% a linéairement amélioré la mobilité des Cd, Cu et Ni avec une augmentation de la mobilité maximum de 35,6, 43,7 et 49,19% pour le Cd, Cu et Ni, respectivement. Pour la plupart des expériences, les ML ont été capturés dans la couche superficielle du sol (0,5 à 1 cm). Néanmoins, des pics de contamination ont été détectés à des profondeurs différentes dans les couches plus profondes du sol. L’étude de la composition des lixiviats montre des variations de concentrations fonction du métal étudié et des caractéristiques du sol et des eaux usées. Des pics de métaux dans le lixiviat sont apparus en même temps que la libération de la matière et / ou la libération de silicates organiques, ce qui démontre l'implication significative des colloïdes dans le transport des métaux. La concentration en sodium (20 mM) a été démontrée un impact fort sur la réduction de la mobilisation colloïdale et que plus de 95% du métal apporté a été détecté dans la couche superficielle du sol en dépit de sa teneur en matière organique. La salinité affiche donc des effets significatifs. L'irrigation avec des eaux usées traitées présentant une très haute teneur en Ca et Mg (111 et 134 mg / L, respectivement) a abouti à la libération moyenne plus élevée de silicium à partir de la matrice inorganique du sol (8,2 mg / L) par rapport à la faible salinité des eaux usées artificielle (1,9 mg / L). Par conséquent, la mobilisation ultérieure de Cd, Cu, Ni et Zn a été observée lorsque le sol a été irrigué avec des eaux usées traitées réelles. Une caractérisation spectroscopique avancée des lixiviats a été réalisée pour identifier les agrégats colloïdaux libérés par le sol dans le but d’en déterminer leur nature, leurs propriétés chimiques et leur état d'agrégation
Reuse of treated wastewater for agricultural purposes is worldwide accepted and practiced to face water scarcity and save high quality resources. Although such practice has undoubtable advantages and is certainly more sustainable respect to the use of fresh water, it is not exempt from severe concerns related to the potential impact on the receiving soil and on the crops of potentially harmful pollutants contained in the reused water at trace levels. Among these pollutants, trace heavy metals (HMs) play a primary role due to their spread presence in the used water and to their persistence once released in the environment. The fate of HMs in the soils can be hardly predicted as mechanisms of mobility through soils are extremely diverse and related to highly complex simultaneous phenomena and chemical equilibria. HMs, in fact, as many other contaminants, are not only partitioned between the solid immobile and the water mobile phases. Indeed, colloids and nanoparticles act as a third mobile phase, with their own rheological properties and velocity. This latter aspect has been one of the main focus of the thesis. In details the thesis describes the results of several experiments conducted irrigating the OECD standard soil with real and/or synthetic wastewater, containing HMs in trace. For each test a specific soil (e.g. varying the organic matter content) and wastewater composition (e.g. varying the metals concentration, the salinity, the organic matter content, or testing real treated wastewaters) has been chosen in order to evaluate the effects of different conditions on the overall HMs fate. The increase of soil organic matter from 2,5 to 10% linearly enhanced the mobility of Cd, Cu and Ni up to a maximum mobility increase of 35.6, 43.7 and 49.19 % for Cd, Cu and Ni, respectively. In most experiments metals accumulated in the top soil layer (0.5 - 1 cm). Nevertheless peaks of contamination were detected at different depths in the soil deeper layers and at different leaching time in the leachates depending on the metal and on the soil and wastewater characteristics. Peaks of metals in the leachate appeared simultaneously with release of organic matter and/or release of silicates, demonstrating outstanding involvement of colloids in metals transport. Sodium concentration (20mM) decidedly reduced colloidal mobilization whereas more than 95 % of the influent metal was detected in the top layer despite the soil organic matter content. Salinity displayed different effects. The irrigation with real treated wastewater with quite high content of Ca and Mg (111 and 134 mg/L, respectively) resulted in higher average release of silicon from the soil inorganic matrix (8.2 mg/L) compared to the low salinity artificial wastewater (1.9 mg/L). Consequently higher mobilization of Cd, Cu, Ni and Zn was observed when the soil was irrigated with real treated wastewater. An advanced spectroscopical characterization of the leachates was performed to identify such colloidal aggregates. The observation of 3D excitation-emission matrix demonstrated in all the leachates samples the presence of fulvic (230-450 nm ex-em fluorescence area) and humic (330-445 nm ex-em) substances. In this context, a novel analytical method was developed to quantify phenolic substances in soil matrices allowing the monitoring of humic matter migration in soil profiles. The novel method was more accurate and more precise respect to the traditional one, allowing to obtain higher recovery of total phenols in peat soil (15.5 % increase) with a decrease of the coefficient of variation (30.1% decrease). Organic water soluble colloids were extracted from the peat used to prepare the OECD standard soil and characterized. Results of size exclusion chromatography highlighted the supramolecular structure of the extracted organic matter. Such structure was further confirmed through fluorescence and 1H-NMR spectroscopy

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CNPQ
Os ditiocarbamatos (carboditioatos) têm sido muito utilizados em operações de pré-concentração de traços de metais por extração (líquido-líquido ou em fase sólida) e co-precipitação. No presente trabalho, apresentam-se os resultados encontrados com a co-precipitação de cobre, níquel, cobalto, chumbo e cádmio empregando piperazina-bis-ditiocarbamato, dietilditiocarbamato e N, N’dibenziletileno bisditiocarbamato sob a forma de compostos do zinco(II). Os reagentes foram preparados a partir da reação entre uma solução da amina correspondente, dissolvida em etanol, alcalinizada com NaOH e resfriada a 10OC com o dissulfeto de carbono (CS2). O precipitado que se forma é separado por filtração e pode ser usado como solução aquosa 1% (m/v) e pode ser conservado por mais de 15 dias. O zinco (II) reage com os ditiocarbamatos de sódio correspondentes e precipita, arrastando os demais metais. O procedimento pode ser executado com soluções com valores de pH entre 6,0 e 9,5 e não é afetado pela ordem de adição dos reagentes. O tempo de centrifugação para deposição da fase precipitada é de 15-30 minutos com uma rotação de 1000-2000 rpm. A co-precipitação simultânea de Cd, Co, Cu, Ni e Pb em níveis de 0,2 g/mL em alíquotas de 50,0 mL de água é possível empregando esta metodologia. As metodologias desenvolvidas foram aplicadas a amostras de água do mar e soluções salinas sintéticas (NaSO4, KCl, NaCl, Na2CO3). Os resultados mostram recuperações superiores a 90% para os metais, exceto para cobalto que tem recuperação superior a 90% apenas quando é empregada a ZnPDC como reagente em soluções salinas 1% (m/v). O método apresentou boa reprodutibilidade e tempo de análise de aproximadamente 4 horas. A metodologia com ZnPDC foi mais precisa para Co e Cu do que as outras metodologias. Sendo o ZnDDC o menos preciso para estes dois metais. Foram realizados experimentos com suporte sólido (naftaleno impregnado com ZnDDC) para a extração de Cd, Co, Cu, Ni e Pb.
The dithiocarbamates (carbodithioates) have been used in operations of pre-concentration of lines of metals by extraction (liquid-liquid or in solid phase) and co-precipitation. In the present work we presented results found for copper co-precipitation, nickel, cobalt, lead and cadmium using the zinc(II) compounds of piperazine-bis-dithiocarbamate, diethildithiocarbamate and N, N' dibenzylethylene bisdithiocarbamate. The reagents were prepared starting from the reaction among a solution of the corresponding amine dissolved in ethanol, alcalized with NaOH and caught a cold to 10O C, with the dissulfide of carbon (CS2). The precipitate that it forms was separated by filtration. The reagent is used as aqueous solution 1% (m/v) and it is stable by 15 days. The zinc (II) reacts with the sodium dithiocarbamates corresponding and co-precipitating with the other metals. The procedure can be executed with solutions with pH values between 4.0 and 10.0, and it is not affected by the order of addition of the reagents. The time of centrifugation is of 15-30 minutes with a rotation of 1000-2000 rpm. A simultaneous co-precipitation of Cd, Co, Cu, Ni and Pb in levels of 0.2 µg/mL in aliquots of 50.0 mL of water are possible using this methodology. The developed methodologies were applied the samples of water of the sea and synthetically saline solution s (NaSO4, KCl, NaCl, Na2CO3). The results show recoveries up to 90%, except for cobalt that has recovery around 90% only when the ZnPDC was used as reagent in saline solutions 1%. The method showed god reproducibility and the time’s analysis during around four hours. The methodology using ZnPDC was more precise to Co and Cu than the others methodologies. The ZnDDC was the less precise for these two metals. We also used a solid support (naphtalene impregnated with ZnDDC) for the extraction of Cd, Co, Cu, Ni and Pb.

In dieser Arbeit wird ein industriell genutzter Metallreiniger auf Basis nichtionischer Tenside untersucht. Dabei werden ausschließlich Messmethoden verwendet, die sich auch für eine industrielle Fertigung eignen. Zu Anfang enthält die Arbeit kurze Abrisse zum gegenwärtigen Kenntnisstand bezüglich der Inhaltstoffe industriell genutzten Reiniger, der Analytik von Tensiden in Reinigern und der Adsorption der Tenside auf Feststoffoberflächen. Im Mittelpunkt der Arbeit steht neben der Charakterisierung und Analyse des Reinigers die quantitative Bestimmung der im Reiniger enthaltenen Tenside in industriellen Reinigungsbädern. Mit Hilfe der Hochleistungsflüssigkeitschromatografie mit einem Verdampfungs - Lichtstreudetektor wird die quantitative Verteilung der Tenside in Reinigungsbädern unter verschiedenen der industriellen Fertigung entsprechenden Bedingungen untersucht. Die Adsorption der im Reiniger enthaltenen Tenside auf der Metalloberfläche unter Fertigungsbedingungen wird mit Fluoreszenzspektroskopie und IR-Spektroskopie quantitativ bestimmt. Im letzten Kapitel wird auf die Umsetzung der gefundenen Ergebnisse in die industrielle Praxis eingegangen.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
This study aimed the evaluation and application of methodology for multielement analyses by total reflection X-ray fluorescence spectrometry (TXRF) in order to provide analyte concentration measurements with accuracy and precision. Using the energy and intensity of the spectral lines of characteristic X-ray, a series of chemicals were identified and quantified, respectively, with a concentration below part per million to a few parts per billion, especially for transition metals. To ensure statistical reliability and reproducibility, a methodology based on the deposition of fine particles, less than 50 m, representative sample and uniformly spread on a quartz flat reflector, which was extremely clean and positioned at the angular condition of maximum reflectivity of monochromatic X-rays was applied. To ensure uniformity on the support surface and the sample representativeness, a number of replicas of specific quantities of samples, in the form of a fine powder was added in a diluted viscous organic solution containing a well-known concentration of an element choosing as internal standard. An aliquot of the viscous solution containing both the suspended particulate sample and an internal standard was deposited at the center of the quartz reflector and dried, yielding a very thin layer of particulates. First, the instrumental TXRF was previously evaluated for its operation, spectral response and recovery of transition metal concentrations in a test sample supplied by the manufacturer. The reproducibility of the elemental concentration measurements was tested with a combination of the number of experimental replicates (five) and analytical (three) for each type of environmental matrix samples, namely certified reference materials or CRMs. Six types of CRMs were tested: river sediment, tomato leaves, rice, fish muscle, bone and bovine liver. The data were statistically processed data, resulting in a series of average and uncertainty values of the analyte concentrations was compared to certified reference values, reported in the technical reports of CRM. Regarding the multielement character of the TXRF technique, there was a good recovery, about 100%, for most of the certified concentrations of the referenced analytes in the six CRMs within the margin of variability of results found by both the TXRF technique and reports. It was also found that the detection limit depends on the density matrix of the material under study. However, the transition elements were those with the lowest values of detection limits. Having a good recovery of majority analyte concentrations in Buffalo River sediment reference material, the same methodology was applied to sediment material analysis of Bezerra stream that was collected in three locations and for a period of three years. A number of chemicals has been identified through their spectral lines K and L and quantified following the internal standard method. The set of concentration data was statistically processed from the point of view of the normality of the data and an analysis of principal components, revealing a systematic presence of high concentrations of heavy metals such as lead and chromium, comparatively higher those recommended by current environmental legislation (CONAMA 420/2009) as the maximum permissible limits.
Este trabalho teve como objetivo a avaliação e aplicação de metodologia para análise multielementar por meio da espectrometria de fluorescência de raios X por reflexão total (TXRF), a fim de fornecer medidas de concentração de analitos com acurácia e precisão. Usando a energia e a intensidade das linhas espectrais de raios X característicos, uma série de elementos químicos foram identificados e quantificados, respectivamente, com concentração abaixo de parte por milhão até poucas partes por bilhão, principalmente para metais de transição. A fim de garantir a confiabilidade e reprodutibilidade estatística, foi aplicada uma metodologia que se baseia na deposição de particulados finos, menores que 50 m, representativos da amostra e uniformemente distribuídos sobre um refletor plano de quartzo, previamente limpo, na condição angular de máxima refletividade de raios X monocromáticos. Para garantir a uniformidade no suporte e a representatividade da amostra, uma série de réplicas de quantidades específicas de amostras, na forma de um pó fino, foi adicionada em solução orgânica viscosa diluída contendo uma concentração conhecida de um elemento na qualidade de padrão interno. Uma alíquota da solução viscosa contendo ambos o particulado de amostra em suspensão e o padrão interno foi depositada no centro do refletor de quartzo e seca, obtendo-se uma camada fina de particulado. Primeiramente, o instrumental TXRF foi previamente avaliado quanto a operação, resposta espectral e recuperação de concentrações de metais de transição de uma amostra de teste fornecido pelo fabricante. A reprodutibilidade das medidas de concentração elementar foi testada com uma combinação da série de réplicas experimentais (cinco) e analíticas (três) para cada tipo de matriz de amostras ambientais, chamadas de Materiais de Referência Certificados ou MRC. Foram testados seis tipos de MCRs: sedimento de rio, folhas de tomate, arroz, músculo de peixe, osso e fígado bovino. Foram processados estatisticamente a série de dados de concentrações elementares de cada MCR, obtendo-se o valor médio e incerteza da concentração de cada analito de referência o qual foi comparado ao reportado nos laudos técnicos dos MCR. Considerando o caráter multielementar da técnica TXRF, verificou-se uma boa recuperação, em torno de 100%, da maioria das concentrações referenciadas e certificadas dos analitos nos seis MCRs, dentro da margem de variabilidade dos resultados encontrados pela técnica TXRF e reportados pelos laudos. Verificou-se também que o limite de detecção depende da densidade da matriz do material sob estudo. Contudo, os elementos de transição foram os que apresentaram os menores valores de limites de detecção. Tendo a boa recuperação das concentrações de analitos maioritários no material de referência sedimento Buffalo River, foi aplicada a mesma metodologia para análise de material de sedimento do córrego Bezerra-Cascavel que foi coletado em três locais ao longo dele e por um período de três anos. Uma série de elementos químicos foram identificados através de suas linhas espectrais K e L, e quantificados seguindo o método do padrão interno. O conjunto de dados de concentração foi processado estatisticamente do ponto de vista da normalidade dos dados e feita uma análise de componentes principais, revelando uma sistemática presença de altas concentrações de metais pesados, tais como chumbo e cromo, comparativamente maiores daqueles preconizados pela atual legislação ambiental (CONAMA 420/2009) quanto aos limites máximos permissíveis.

[cat] S'estudia l’estat actual del contingut de set macroelements (Ca, Mg, Al, Fe, K, Na i P) i nou elements traça (As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn) en els sòls de les Illes Balears. A partir de la determinació del contingut total de macroelements i elements traça mitjançant la digestió de les mostres de sòl per via humida amb aigua règia i s’estudien les relacions que hi ha entre ells i amb les característiques fisicoquímiques del sòl. També s’estudia el comportament dels elements en funció de l’illa, la profunditat i a una sèrie de sòls representatius de les Illes Balears. Finalment, s’estableix una proposta de nivells de fons i valors de referència dels elements traça a les Illes Balears comparant diferents mètodes, amb la finalitat de poder tenir criteris que permetin identificar una possible alteració dels continguts d’aquests elements. Els continguts medians (mg kg-1) obtinguts pels elements traça estudiats a les mostres superficials han estat: As 15,8, Cd 0,42, Co 9,6, Cr 57,3, Cu 18,7, Mn 467,1, Ni 29,3, Pb 18,7, Zn 53,9. Respecte el comportament en funció de l’illa, el Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn presenten valors més baixos de concentració a Formentera i els més alts a Menorca, amb situacions intermèdies a les altres dues illes, més semblants a Menorca en el cas de Mallorca i més semblants a Formentera en el cas d’Eivissa. L’As no presenta diferències de concentració entre illes. Aquest comportament dels elements traça és invers al del CCE i del pH, així, llocs on tenen un contingut elevat de carbonats tenen un baix contingut d’elements traça. Les correlacions entre la majoria de paràmetres estudiats són significativament altes (p<0,05) o molt altes (p<0,001). Tot i això, els coeficients dels llims, CO, pH, Na, P i Mg amb la resta de paràmetres són relativament baixos, indicant un baix efecte d’aquests paràmetres sobre els elements traça. Les relacions entre l’Al, Fe, K, As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn són altament significatives i presenten majoritàriament coeficients positius elevats entre ells, suggerint un origen comú i natural d’aquests. Pel que fa l’estudi dels elements traça sobre sòls representatius de les Illes Balears s’ha observat que sobre materials calcaris, els sòls menys diferenciats presenten els continguts més baixos d’elements traça i els més evolucionats són els que presenten els continguts més elevats. Per ordre, els continguts més baixos corresponen als Arenosols de sistemes dunars litorals, seguits de Cambisols sobre margues, Calcisols, Cambisols sobre margues i, finalment, Luvisols com a tipologies més diferenciades i amb continguts d’elements traça més elevats. D’altra banda, sobre les roques olivíniques del Keuper es desenvolupen sòls amb alts continguts de P, Fe, Co, Cr, Mn i Ni i baixos de Cd. Els rangs de concentració (mg kg-1) de la població de fons dels diferents elements traça per als sòls de les Illes Balears amb el mètode del gràfic de probabilitat han estat: As 2,5-28,2, Cd 0,03-0,74, Co 1,7-16,9, Cr 12,9-95,3, Cu 2,6-32,6, Mn 53,3-793,5, Ni 5,5-49,6, Pb 0,3-34,7, Zn 9,6-96,4. Els valors mitjans de la població de fons han resultat molt semblants amb els cinc mètodes utilitzats. Tot i això, s’aprecia que el rang més ampli de població de fons, i per tant el valor de referència més alt, s’ha obtingut amb el mètode del diagrama de caixes, seguit dels mètodes del rang normal d’una mostra, del de la funció de la distribució calculada, del mètode del gràfic de probabilitat i, per acabar, del mètode de la mediana, amb el que s’obté el rang més estret, i per tant del valor de referència més baix.
[spa] Se han investigado 508 perfiles de las Islas Baleares y la variabilidad en ellos de los niveles de macroelementos (Ca, Mg, Al, Fe, K, Na i P), elementos traza (As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn) y algunas propiedades del suelo (arenas, limos, arcillas, carbonato cálcico equivalente -CCE-, carbono orgánico, pH y capacidad de intercambio catiónico). Los puntos de muestreo seleccionados presentaban una mínima influencia antropogénica y las muestras de suelo fueron recogidas para cada horizonte de cada perfil. Para el análisis de macroelementos y elementos traza las muestras fueron digeridas usando agua regia y horno microondas. Las concentraciones medias de elementos traza (mg kg-1) obtenidas en horizontes superficiales fueron: As 15,8, Cd 0,42, Co 9,6, Cr 57,3, Cu 18,7, Mn 467,1, Ni 29,3, Pb 18,7, Zn 53,9. Los resultados obtenidos del análisis estadístico revelan correlaciones significativas entre la mayoría de elementos y el contenido de CCE, arcillas y materia orgánica, indicando que las concentraciones de estos elementos se encuentran controladas por las características del suelo. La concentración de elementos traza es relativamente baja en áreas con elevado contenido de CCE, así la concentración de carbonatos en el suelo es un factor determinante en la presencia y distribución de elementos traza en los suelos del área estudiada. Con respecto a la profundidad, se observa un incremento del contenido de arcillas y pH al aumentar ésta y una disminución de la materia orgánica. Respecto los elementos traza, el Cu, Pb Cd, Mn y Zn presentan una disminución en función de la profundidad, mientras que el As, Co, Cr i Ni no presentan diferencias significativas entre los horizontes comparados. Por lo que se refiere a los suelos desarrollados en cada grupo de referencia se encontraron claras diferencias: sobre calcáreas, los suelos poco desarrollados presentan las concentraciones más bajas de elementos traza, mientras que los suelos diferenciados presentan las mayores concentraciones. En orden ascendente de concentración, el menor contenido corresponde a Arenosols de sistemas dunares litorales, seguidos por los Cambisols sobre margas, Calcisols, Cambisols sobre margas y, finalmente, Luvisols como la tipología más diferenciada y con el mayor contenido de elementos traza. Por otro lado, en suelos desarrollados sobre rocas olivínicas del Keuper aparecen altos contenidos de P, Fe, Co, Cr, Mn y Ni y bajas concentraciones de Cd. Por último se estableció la concentración de niveles de fondo y de referencia. Los valores de referencia obtenidos a partir de gráficos de probabilidad fueron(mgkg): As 28,2, Cd 0,74, Co 16,9, Cr 95,3, Cu 32,6, Mn 793,5, Ni 49,6, Pb 34,7, Zn 96,4.
[eng] In this work, 508 soil profiles of Balearic Islands (European Mediterranean region) were investigated, and the variability in the levels of major elements (Ca, Mg, Al, Fe, K, Na i P), trace elements (As, Cd, Co, Cr, Cu, Mn, Ni, Pb i Zn) and some soil properties (sands, silts, clays, calcium carbonate equivalent -CCE-, organic carbon, pH and cation exhange capacity) was examined. Sampling sites with minimal antrhropogenic influence were selected and soil profile samples were analysed for major and trace element content. The soil samples were collected from every horizon in each profile and the samples were digested using aqua regia and microwave oven for pseudo-total trace elements. The median concentrations of trace elements (mg kg-1) obtained in surface horizons were: As 15.8, Cd 0.42, Co 9.6, Cr 57.3, Cu 18.7, Mn 467.1, Ni 29.3, Pb 18.7, Zn 53.9. The results obtained from the statistical analysis reveal significant correlations between most elements and CCE, clay and organic matter contents, indicating that metal concentrations are controlled by soil composition. The trace element concentration is relatively low in areas of high CCE, therefore carbonate concentration in soil is the determining factor in the presence and distribution of trace elements in the soils of the studied area. According to depth, Cu, Pb, Cd, Mn and Zn show an increase with depth, in the same way of clays and pH. As, Co, Cr and Ni do not show statistical differencies between horizons. A clear distinction was found between the metal content of the soils developed in each Reference Soil Group: Over limestones, poor-developed soils show the lowest concentrations of trace elements while well-developed soils have the highest concentrations. In ascending order of concentration, the lowest content correspond to Arenosols of litoral dune systems, followed by Cambisols over marls, Calcisols, Cambisols over marls and, finally, Luvisols as most differenciated tipologies and with higher trace element contents. On the other hand, over Keuper olivinic rocks soils with high concentrations of P, Fe, Co, Cr, Mn and Ni and low concentrations of Cd are developed. The background concentration and reference values have also been stablished. The reference values obtained in this study through probability plots were (mgkg): As 28.2, Cd 0.74, Co 16.9, Cr 95.3, Cu 32.6, Mn 793.5, Ni 49.6, Pb 34.7, Zn 96.4.

Mercury is one of the most harmful non-essential elements to wildlife for its ability to bioaccumulate and bioamplify throughout the food chain. Due to the continuous increase in concentration of this element, birds of prey are often used as biomonitors due to their wide habitat diversity and high probability of contaminant accumulation as top predators. In the present work, the concentration of mercury in 10 tissues (nails, beak, feathers, liver, kidneys, lungs, heart, muscle, brain and skin) of four birds of prey was analyzed: common buzzard (Buteo buteo) , eurasian sparrowhawk (Accipiter nisus), common kestrel (Falco tinnunculus) and little owl (Athene noctua) and evaluated the influence of parameters such as gender and age on the accumulation of this element. The results showed significant differences between tissues in the order of concentrations: skin < brain< muscle < heart < lungs < liver < kidneys < feathers < nails < beak. Significant differences were observed between the different species, in which the eurasian sparrowhawk and the common buzzard presented the highest values. The age group influenced the accumulation in the common kestrel, where subadults presented higher values than those shown in adults, with no differences regarding gender. For the remaining bird species no significant differences were identified for variation of accumulation with gender or age.
O mercúrio é um dos elementos não-essenciais mais prejudiciais à vida selvagem, pela sua capacidade de bioacumular e bioamplificar ao longo da cadeia alimentar. Devido ao contínuo aumento de concentração deste elemento, as aves de rapina são frequentemente utilizadas como biomonitores devido à sua vasta diversidade de habitats e elevada probabilidade de acumulação de contaminantes por serem predadores de topo. No presente trabalho foi analisada a concentração de mercúrio em 10 tecidos (unhas, bico, penas, fígado, rins, pulmões, coração, músculo, cérebro e pele) de quatro aves de rapina: águia-d’asa-redonda (Buteo buteo), gavião-europeu (Accipiter nisus), peneireiro-comum (Falco tinnunculus) e mocho-galego (Athene noctua) e avaliada a influência de parâmetros como género e idade na acumulação deste elemento. Os resultados obtidos evidenciaram diferenças significativas entre os tecidos, pela ordem de concentrações: pele < cérebro < músculo < coração < pulmões < fígado < rins < penas < unhas < bico. Foram observadas diferenças significativas entre as diferentes espécies, em que o gavião-europeu e a águia-d’asa-redonda apresentaram os valores mais elevados. A faixa etária influenciou na acumulação no peneireiro-comum, em que subadultos apresentaram valores superiores aos demonstrados nos adultos, não sendo observadas diferenças em relação ao género. Para as restantes espécies de aves não foram identificadas diferenças significativas para a variação da acumulação com o género ou idade.
Mestrado em Ecologia Aplicada

碩士
國立中山大學
海洋科學系研究所
103
Sea anemones in Kueishantao Islet inhabit in environments with low pH and high metal concentrations. In this study, comparisons on sea anemone morphology and accumulation of trace metals among vent and non-vent sites were determined. The experiments were divided into 5 parts. Firstly, extracellular pH (pHe) of sea anemones between vent and non-vent sites was compared. Secondly, the morphology of Anthopleura sp. from different vent sites was compared. Thirdly, the survival rates of transplanted Aiptasia pulchella to different vent sites were evaluated. Fourthly, the anatomy of sea anemones of Anthopleura sp., Actinia equina and A. pulchella from vent and non-vent sites was studied. Fifthly, the concentration of trace metals in sea anemones from vent and non-vent sites was studied. The pHe of sea anemones was significantly different between vent and non-vent sites. With 0.5 hr exposure duration, factors of vent types (white vs. yellow), distance to vents (5 vs. 30 m) and vent directions (east vs. south) all affected the survival of transplanted A. pulchella. Body size of Anthopleura sp. was significantly different among vent directions. It is suggested that differential food amount transported by local currents is a major cause. The length/width ratio of basitrich had significant difference between west and other directions. In spirocyst, significant difference was found between east and west directions. Anthopleura sp. and A. equina are asymbiotic sea anemones. The accumulation pattern of trace metals in sea anemones of Anthopleura sp. and A. pulchella was different and Ca element was the dominant contributor to the separation.

碩士
高雄醫學院
藥學研究所
85
Abstract Tannery wastewater containing toxic metal chromium may contaminate environment. The purpose of this study was to examine the heavy metal content of tannery wastewater. All samples were acidified with nitric acid, digested in a microwave oven, and filtered with 0.45 μｍ filter before analysis. The analytical technique for metal conten determination was by the graphite furnace atomic absorption spectrophotometry. The results of the best ashing temperatures for copper, lead, chromium, cadmium, cobalt, silver and nickel were 800, 450, 800, 300, 800, 400 and 900 ℃, respectively. The best atomization temperatures were 2300, 1900, 2400, 1800, 2300, 2050 and 2400 ℃, respectively. Microwave digestion was superior to conventional digestion for nickel, cadmium, silver and chromium but for copper, cobalt, and lead conventional digestion was better than microwave digestion. Threes samples from the wastewater and one from groundwater in the tannery plant were examined. The one coming from groundwater represented the metal's background concentration of the wastewater. The results showed that (1) the concentrations of cadmium, nickel, cobalt, lead, copper and silver in wastewater closed to the one from groundwater that indicated those metals in wastewater coming from groundwater. (2) The chromium concentration (1.11 ppm) in the wastewater was higher than in the groundwater that was significantly reduced, lower than detection limit 0.5 ppb, following coagulation with PAC. The results of examining seven metals in the tannery wastewater using proved analysis procedures suggested that the wastewater was no adverse impact on ambient environment. Seven more samples were sampled for chromium examination:two in manufacture process and five in open channel outside the plant. The concentrations were 4254 and 128.4 ppm in the manufacture process indicating that the wastewater may cause heavy pollution on the surrounding environment if the plant did not have a well-defined treatment process. The longer distances have higher chromium concentration that possibly causeed by other plant's wastewater contained chromium in neighboring.

碩士
國立中山大學
海洋生物科技暨資源學系研究所
95
The purposes of this study were to establish the reference values of element concentrations and to estimate the food safety and the nutrient values of essential elements in the aquaculture fish products in Taiwan. 31 species of fishes, 4 species of crustaceans and 3 species of molluscs were collected from 11 aquaculture areas in Taiwan from September to November in 2004 to 2006. Concentrations of Ag, As, Cd, Co, Cu, Fe, Hg, Mn, Se, Sr and Zn in the muscles were analyzed. The results showed that the concentrations of those elements had significant difference among teleosteans, crustaceans and molluscs, excepted Hg and Se. Essential element concentrations in Cu, Sr and Zn were higher in invertebrates (shellfishes) than in vertebrates (teleosteans) but Co, Fe and Mn were higher in molluscs than others. All concentrations of non-essential elements excepted Hg were higher in molluscs. Significant species-differences were also found in our results, but not in the concentrations of Ag and Co in teleosteans. Among teleosteans, Trachinotus blochii (As and Se), Anguilla japonica (Cd and Zn), Lates calcarifer (Cu), Carassius auratus auratus (Fe), Epinephelus coioides (Hg), Rachycentron canadum (Hg) and Chanos chanos (Mn and Sr) contained the highest concentrations, showed in parenthesis. Whereas among shellfishes, Haliotis diversicolor (Ag), Meretrix lusoria (As, Cd, Co, Fe, Mn, Se and Sr), Corbicula fluminea (Co and Se), Scylla serrata (Hg and Zn) revealed the highest concentrations of those elements. The results were seminar to previous literatures reported for uncontaminated aquatic environment area worldwide, so they could be the reference values of element concentrations in the aquaculture fish products in Taiwan. The element concentrations in this study were all below the worldwide food safety standards of inorganic As = 1.0, Cd (for fish and crustaceans) = 0.2, Cd (for mollusks) = 2.0, Cu = 10, total Hg = 0.5, Se = 1.0 and Zn = 50 μg / g wet wt. Based on the normal dietary habit of Taiwanese by consume 400g fishes and 200g shellfishes every week, the element concentrations of weekly intake were bellowed the standards of inorganic As = 15, Cd = 7 and organic Hg = 1.6 μg / kg of body / week by PTWI, and could obtain more than 100% to Co and 58% to Se of RDA standards at the same time.

碩士
國立清華大學
生醫工程與環境科學系
104
Till date, as the technical innovations in industry, several instrument analytical methods have started in improvement of analytical efficiency and device function. However, the more accuracy we improved in the determination of metal elements result in the more complicated experimental procedures and expensive instruments in each method. What’s more, that will cost us much more manpower, time and money. Thus, the idea of on-site or even home determinations start to stand out and contribute to parts of analytical technologies developing towards miniaturization, automation and commercialization. However, when we in the analytical determination process, we still cannot eliminate the procedure to prepare the reagent and the calibration curve we need. Here, based on the idea of “miniaturized total analysis system”, this study proposed an innovative strategy for simplifying the procedure of calibration curve setting to compensate for the deficient we just mentioned above. With this novel microfluidic analytical system, we can build up a high-adaptable analytical platform in an easier way. Based on the experimental results, we have developed two analytical determination systems. For the first analytical system, we use poly(methyl methacrylate), which is cheap and easy to fabricate, as materials to build up the first-generation of concentration gradient generator Then, we couple the commercial kit with the developed microchip to approve our ability to become commercialized. For the second analytical system, we apply the idea of “microfluidic paper-based analytical devices, -PADs” to our microchip which is very popular in this decade. Only with a piece of paper, we can build up the second-generation of concentration gradient generator easily. The second-generation microchip not only solve the problems in the first generation, like complicated fabrication process and lack of injector driving force, but also couple the colorimetric method and smartphone application to determine the concentration of chromium (Ⅵ) in the groundwater.

An in situ experiment was conducted at the Equity Silver mine, near Houston, British Columbia in an attempt to induce hepatic metallothioneins and study metal uptake in rainbow trout (Oncorhynchus mykiss)using acid rock drainage (ARD). A mesocosm apparatus consisting of 16 flow-through troughs were placed over Foxy Creek, and fish were placed tubs at the end of selected troughs. Dilution rates of ARD:stream water were 0:1 (control), 1:25000, 1:10000, 1:2500, 1:1000, 1:250, and 1:25. Bioaccumulation of copper, zinc and cadmium was determined in the liver, gill and muscle tissue using atomic absorption spectroscopy. Hepatic metallothionein concentrations were measured using differential pulse polarography. Metal concentrations in the troughs were analyzed using inductively coupled argon emission spectroscopy. The water chemistry data was modelled using the geochemical model MINTEQA2 in an attempt to estimate metal bioavailability. It was concluded that pH and adsorbtion processes in the experimental troughs played a very important role in controlling the ARD toxicity. Hepatic metallothioneins were not elevated above background levels after23 days of exposure to various concentrations of ARD. Significant metal bioaccumulation occurred with zinc, and the source appeared to be the food which the experimental fish were fed. The 48 hour LC50 was calculated to occur when roughly 1 part ARD was mixed with 1400 parts stream water. At this mixing rate, the pH of the stream would have been reduced from 7 to roughly 6.8, and copper, zinc, aluminum and cadmium concentrations would have been 0.028, 0.027, 0.277 and 0.0003 mg•L-1respectively. The 23 day LC50 was calculated to occur when roughly 1 part ARD was mixed with 5150 parts stream water. At this dilution, the pH would have not been reduced below neutrality, and the copper, zinc, aluminum and cadmium concentrations would be 0.010, 0.014, 0.113 and 0.0001 mg•L-1 respectively.

This study assesses the presence of selected trace metals and pops in the Baynespruit River, Sobantu, KwaZulu-Natal. Sediments, plants and water samples were collected along the river during dry and wet season. For metal analysis, the extraction was done using acid digestion and then determined on the inductively coupled plasma atomic emission spectroscopy, for total metals in sediments, plants and water. Bio-available metals in sediments were analysed using atomic absorption spectroscopy. POPs were extracted in sediments using soxhlet extraction, which was followed up by evaporation on the rotary evaporator, sample clean up on a GPC column, further sample concentration on the rotary evaporator and later analysed on GC/MS instrument. Metals of concern in both seasons were Cu, Cr, Pb and Zn which exceeded maximum permissible limits for South African soil, Cr was just about the maximum permissible limit. The targeted POPs were not detected on any site during this work.
Environmental Sciences
M. Sc. (Environmental Science)

La présente étude porte sur l’évaluation d’une méthode d’acquisition de la solution de sol présente à l’interface sol-racine, dans la rhizosphère. Cette interface constitue le lieu privilégié de prise en charge par les plantes des contaminants, tels que les métaux traces. Comme les plantes acquièrent ces éléments à partir de la phase liquide, la solution de sol de la rhizosphère est une composante clé pour déterminer la fraction de métaux traces biodisponibles. La microlysimétrie est la méthode in situ la plus appropriée pour aborder les difficultés liées à l’échelle microscopique de la rhizosphère. Ainsi, dans les études sur la biodisponibilité des métaux traces au niveau de la rhizosphère, les microlysimètres (Rhizon©) gagnent en popularité sans, toutefois, avoir fait l’objet d’études exhaustives. L’objectif de cette étude est donc d’évaluer la capacité de ces microlysimètres à préserver l’intégrité chimique de la solution, tout en optimisant leur utilisation. Pour ce faire, les microlysimètres ont été soumis à une série d’expériences en présence de solutions et de sols, où la quantité de solution prélevée et le comportement des métaux traces (Cd, Cu, Ni, Pb, Zn) ont été étudiés. Les résultats montrent que les microlysimètres fonctionnent de façon optimale lorsque le contenu en eau du sol est au-dessus de la capacité au champ et lorsqu’il y a peu de matière organique et d’argile. Les sols sableux ayant un faible contenu en C organique reproduisent mieux le volume prélevé et la solution sous la capacité au champ peut être récoltée. L’utilisation des microlysimètres dans ces sols est donc optimale. Dans les essais en solution, les microlysimètres ont atteint un équilibre avec la solution après 10 h de prélèvement. En respectant ce délai et les conditions optimales préalablement établies (pH acide et COD élevé), les microlysimètres préservent la composition chimique de la solution. Dans les essais en sol, cet équilibre n’a pas été atteint après dix jours et huit prélèvements. Le contenu en matière organique et l’activité microbienne semblent responsables de la modification des concentrations en métaux au cours de ces prélèvements, notamment, dans l’horizon FH où les microlysimètres performent très mal. En revanche, dans l’horizon B, les concentrations tendent à se stabiliser vers la fin de la série de prélèvements en se rapprochant des valeurs de référence. Bien que des valeurs plus élevées s’observent pour les microlysimètres, leurs concentrations en métaux sont comparables à celles des méthodes de référence (extrait à l’eau, lysimètres de terrain avec et sans tension). En somme, les microlysimètres se comportent généralement mieux dans l’horizon B. Même si leur utilisation est plus optimale dans un sol sableux, cet horizon est privilégié pour de futures études sur le terrain avec les microlysimètres.
This study focuses on evaluating a method of acquiring soil solution in the soil-root interface of the rhizosphere. The liquid phase of the rhizosphere constitutes the main area where plants absorb contaminants like trace metals. Thus the rhizosphere soil solution is key to determine the amount of bioavailable trace metals. Microlysimetry has been described as the most appropriate in situ method to tackle difficulties inherent to the microscopic scale of the rhizosphere. Despite the lack of an exhaustive evaluation of their performance, microlysimeters have gained popularity for in situ studies on the bioavailability of trace metals. The objective of this study was to evaluate the capacity of microlysimeter to preserve the chemical integrity of the soil solution and also to determine their optimum use conditions. To do this, microlysimeter have been submitted to a series of laboratory experiments with solutions and soils. The volume of solution extracted and trace metals (Cd, Cu, Ni, Pb, Zn) behaviour were studied. Results show that microlysimeters work optimally when soil water content is above field capacity and when the amount of clay and organic matter is low. Sandy soils with low organic carbon content have a better reproducibility for extracted volume and soil solution extraction is possible even when soil water content is below field capacity. Using microlysimeters in this soil type is thus optimal. In solution experiments, microlysimeters reached equilibrium with the control solution after ten hours of extraction. In optimal conditions (acidic pH and high DOC) and after this ten hours period, microlysimeters preserve the chemical composition of the solution. In soil experiments, this equilibrium has not been reached after eight samplings throughout ten days. Organic matter content and microbial activity could be responsible for the modification of concentrations of trace metals during sampling. This is especially true for FH horizon where microlysimeters perform poorly. In contrast, the concentrations reach the reference values toward the end of sampling serie in the B horizon and microlysimeters have a better overall performance in this horizon. Although higher values are observed for microlysimeters, trace metals concentrations are comparable to other extraction methods, specifically for the B horizon. Even if their uses are optimized in sandy soil, the B horizon should be privileged for future field studies involving microlysimeters.

碩士
國立清華大學
原子科學系
89
A method for determination of concentration gradient of trace levels of transition metals (Cu, Zn, Cr, Co and Ni) in silicon wafer using anodic oxidation combined with microconcentric nebulizer equipped inductively coupled plasma mass spectrometry (MCN-ICP-MS) has been developed and optimized. Firstly, developing an anodic oxidation technique for uniform growth of silicon-dioxide (SiO2) layer on silicon wafer and subsequent characterization of the physical properties of the layer formed. The thickness of oxide layer was measured both by SEM and ICP-OES, and the results obtained were found to be in good agreement. The influences of current density, electrolyte composition and electrolysis time on the growth of SiO2 film on the silicon wafer by anodic oxidation were studied. Based on the experimental results, anodic oxidation of a 4-inch single crystalline silicon wafer was carried out in constant current density mode with 0.08 M HNO3 as electrolyte at room temperature. Under the anodization condition at a constant current density of 0.346 mA/cm2 and electrolysis time of 2 hr, a silicon dioxide layer with thickness of about 1000 Å can be obtained. Secondly, the optimum conditions of MCN-ICP-MS for the determination of trace metal concentrations were investigated. After anodic oxidation the oxide layers were subsequently dissolved with dilute HF, and the resulted solutions were subjected to ICP-MS for the determination of analyte concentrations. The interference effects caused by the silicon matrix and acid medium in the instrumental determination step were investigated and minimized. The detection limits achievable with the present system for the determination of Co, Cr, Cu, Ni, and Zn can be down to the sub-ppb levels. Finally, the analytical system combined with anodic oxidation and MCN-ICP-MS was tested for its applicability for determination of concentration gradient of trace metals in silicon wafer. From the prelimary study on a silicon wafer heavily polluted with trace metals, it indicated that a general trend showing decrease of analyte concentration with increasing depth, which is in agreement of literature report, could be achieved. In conclusion, the established system of anodic oxidation combined with MCN-ICP-MS was found to be feasible for the determination of concentration gradient of trace metals in silicon wafer.