Abstract The objective of this study is to investigate the heavy metal pollution in our environment by sampling and analyzing the concentration of heavy metal in seawater, sediment, and aquatic organisms from the seaside along the Chang-hua Coastal Industrial Park. The Chang-hua Coastal Industrial Park, located by the west coast of Chung-hua county in middle Taiwan, is a large-scale and multi-functional industrial estate with industrial production, residence and leisure possibilities. Hsienhsi District is situated at the northern part of the Industrial Park. Lukang District is at the southern part. In the middle of it, it is Lunwei District. In the Chung-hua Coastal Industrial Park, there are the second most electroplate and metal coating factories in Taiwan. Metal waste from the process of electroplating and coasting could easily pollute the tidal flat in Chang-hua Coastal Industrial Park. In order to prevent potential pollution taking place, this study took seawater, segment, and the aquatic organisms from the coast of the Chung-hua Coastal Industrial Park to monitoring the concentration level of copper(Cu), zinc(Zn), nickel(Ni), lead(Pb), chromium(Cr) and cadmium(Cd) in each index. The bioconcentration factor (BCF) indicates distinctions of accumulation in various matrixes. Especially from BCFW and BCFS demonstrate that soldier crab is a better index to illustrate the accumulation of Pb and Cr. Muricidae is a better index for showing Cd accumulating concentration. Furthermore, saccostreamordax is the best index for illustrating accumulative level of Ni. Oyster is better in showing accumulating of Cu and Zn. Though each organism shows distinct accumulation of particular metal, they can still illustrate the concentration of other selected metals to image the pollution of the environment. The comparison of metal accumulating levels in seawater, segment, and aquatic organisms from each test site demonstrated: the heavy metal concentration at site2 was much higher than at the other sites. The second most heavy metal concentration was at site6 and site8. Matrixes at site4 contained the lowest heavy metal concentration. The result was thought to be caused by current capacities of factories in three districts of Chang-hua Coastal Industrial Park. Site2 was at Hsienhsi Districtin, in which contained about 58% of factories in residence. In Lukang District, it reached the highest-77%-where was site 6 and site 8. In terms of Site4, it situated at Lunwei District, where was Lunwei Harbor Reservation with least development following by least capacity of factories. Furthermore, without a sound environmental-protection biological sewage treatment device, residues and chemical waste produced from various highly contaminant industries would bring about this concentration comparison result as well.

Few studies have been conducted on the effectiveness of phytoremediation of pharmaceutical compounds, although the persistent and non-acutely toxic nature of many of these compounds in today's water bodies may yield an ideal application for this practice. To quantify the potential effectiveness of plant uptake, kinetic and proportional bioconcentration factors (BCFk, and BCFp, respectively) in nanograms (ng) carbamazepine and amiodarone per gram (g) wet weight plant tissue for Lemna spp. were determined utilizing a 14-day continuous flow-through study. Samples were analyzed using isotope dilution liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) running in positive ion mode. Kinetic BCF was estimated at 0.538, while proportional BCF was estimated at 0.485. Kinetic BCF for the amiodarone study was estimated at 23.033, whereas proportional BCF was estimated at 41.340. Possible contamination of the C18 column and peristaltic pump failure may have impacted uptake results. In light of variability and current lack of research in the field, this work should be considered exploratory rather than conclusive.

Submitted by GILBERTO DIAS DE ALKIMIN null (gilberto_cdz@hotmail.com) on 2016-04-15T17:08:54Z No. of bitstreams: 1 Dissertação_FINAL.pdf: 6110695 bytes, checksum: c7822bb8a9272890beb5ba8faae113c6 (MD5) / Approved for entry into archive by Felipe Augusto Arakaki (arakaki@reitoria.unesp.br) on 2016-04-19T19:40:04Z (GMT) No. of bitstreams: 1 alkimin_gd_me_soro.pdf: 6110695 bytes, checksum: c7822bb8a9272890beb5ba8faae113c6 (MD5) / Made available in DSpace on 2016-04-19T19:40:04Z (GMT). No. of bitstreams: 1 alkimin_gd_me_soro.pdf: 6110695 bytes, checksum: c7822bb8a9272890beb5ba8faae113c6 (MD5) Previous issue date: 2016-02-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A contaminação dos ambientes aquáticos por metais é uma preocupação mundial, pois são elementos bioacumulativos e persistentes. Diversos desses compostos possuem a capacidade de alterar o sistema endócrino (denominados interferentes endócrinos – IE), sendo o cádmio (Cd) e o zinco (Zn) suspeitos dessa atuação, segundo a literatura. Para verificação dessa potencialidade algumas análises biológicas são indicadas como: 1) a realização do teste de dessorção no auxílio ao posterior cálculo do fator de bioconcentração (FBC), para detecção do real valor incorporado do contaminante pelo organismo e predição dos efeitos tóxicos causados; 2) análises histológicas de órgãos como as gônadas e o fígado e 3) análise de vitelogenina (VTG) no fígado de machos. Dessa forma o objetivo deste trabalho foi averiguar a atuação endócrina dos metais Cd e Zn em concentrações permitidas em ambientes aquáticos para a proteção da vida aquática por meio de: a) estudo do tempo de dessorção de Cd e Zn da parte externa do organismo; b) determinação do FBC de Cd e Zn em D. rerio após exposição crônica; c) avaliação da possibilidade de Cd e Zn provocarem alterações histológicas em gônada e fígado de machos e fêmeas de D. rerio e d) análise da capacidade de Cd e Zn em induzir a produção de VTG no fígado de machos de D. rerio. Para a realização do teste de dessorção, organismos adultos de D. rerio, foram expostos por 72 horas a Cd (1 µg de Cd/L) e Zn (180 µg de Zn/L) seguindo-se a lavagem do organismo-teste em ácido nítrico 2% por diferentes tempos (0h; 5; 60; 90; 120; 150 e 180 minutos) e posterior construção da curva de dessorção. As análises de FBC, histologia e histoquímica foram realizadas após exposição crônica (21 dias) em regime semi-estático, com troca total da solução a cada 72 horas, em separado a concentrações permitidas por legislação nacional (1 µg de Cd/L e 180 µg de Zn/L) e internacional (0,25 µg de Cd/L e 120 µg de Zn/L) para proteção da vida aquática. Desse modo, após o final da exposição organismos foram levados a digestão, leitura da concentração do contaminante e o FBC foi calculado, bem como machos e fêmeas foram sacrificados e passaram por procedimento de preparo histológico, corados com hematoxilina e eosina e análise qualitativa de gônada e fígado e machos após preparo histológico sofreram marcação histoquímica para detecção de VTG no fígado. Pelos resultados obtidos, verificou-se que a dessorção dos metais apresentou diferença, sendo a dessorção de Cd realizada em 90 minutos e a de Zn em 60 minutos; a bioconcentração de Cd foi semelhante nas duas concentrações de exposição e a de Zn foi inversamente proporcional à concentração exposta. As análises histológicas mostraram que Cd e Zn provocam alterações de forma pronunciada tanto em gônadas quanto em fígados de fêmeas, enquanto gônadas de machos não sofreram graves alterações e os fígados apresentaram lesões que podem comprometer o funcionamento do órgão, além disso, observou-se a produção de VTG no fígado de machos de D. rerio expostos a Cd e Zn. Por fim, a união das técnicas utilizadas comprova que Cd e Zn, mesmo em concentrações permitidas por legislação são capazes de atuarem como IE em D. rerio, necessitando de mudanças na legislação para valores mais restritivos com a finalidade de garantir a saúde endócrina dos organismos aquáticos. / The contamination of aquatic environments by metals is a global concern because they are bioaccumulative and persistent elements. Several such compounds have the ability to change the endocrine system (called endocrine disruptors - ED), and cadmium (Cd) and zinc (Zn) that suspicious activity, according to the literature. To verify the potential some biological analyzes are given as: 1) the realization of the desorption test to aid the subsequent calculation of bioconcentration factor (BCF), for determining the real corporate value of the contaminant by the body and prediction of toxic effects; 2) histological analysis of organs such as the gonads and liver and 3) analysis of vitellogenin (VTG) in the liver of males. Thus the aim of this study was to determine the endocrine actions of Cd and Zn in allowed concentrations in aquatic environments for the protection of aquatic life through: a) study time desorption of Cd and Zn from outside the body; b) determination of CBF of Cd and Zn in D. rerio after chronic exposure; c) assessment of the possibility of Cd and Zn cause histological changes in the liver and gonads of males and females of D. rerio d) analysis of the ability of Cd and Zn in inducing the production of VTG in the liver of males of D. rerio. To perform the desorption test, adult organisms of D. rerio were exposed for 72 hours Cd (1 µg/L of Cd) and zinc (180 µg/L of Zn) followed by washing of the organism under test 2% nitric acid for different times (0 h, 5, 60, 90, 120, 150 and 180 minutes) and subsequent construction of desorption curve. The analyses of BCF, histologic and histochemical were performed after chronic exposure (21 days) under semi-static system, with complete exchange of the solution every 72 hours in separat concentrations allowed by national legislation (1 µg of Cd/L and 180 µg of Zn/L) and international (0.25 µg Cd/L and 120 µg Zn/L) for protection of aquatic life. Thus, after the end of exposure organisms were taken digestion, of the contaminant concentration of the reading and the CBF was calculated as well as males and females were euthanized and underwent histological preparation procedure, stained with hematoxylin and eosin and qualitative analysis of gonads and liver histological was performed and males after preparing suffered histochemical staining VTG detection in the liver. This waythe desorption of metals it was different, with desorption of Cd performed in 90 minutes and Zn in 60 minutes, the bioconcentration of Cd was similar in both exposure concentration and the Zn was inversely proportional to the concentration exposed, histological analyzes show that Cd and Zn cause pronounced changes in both gonads, as in female livers, but the gonads of male suffered no serious changes and livers showed lesions that can compromise the function of organ, besides, it was observed VTG production in the liver D. rerio males exposed to Cd and Zn. Finally, the union of techniques shows that Cd and Zn, even at concentrations allowed by law are able to act as IE in D. rerio, requiring changes in legislation for more stringent values in order to ensure the endocrine health organisms water.

Heavy metal contamination of soil and agricultural products is an environmental problem, has an adverse effect on the quality of food crops, and is a danger to food security and public health. The concentration of arsenic (As), cadmium (Cd), lead (Pb), iron (Fe) and zinc (Zn) in surface soils and edible hypocotyls tissues of two ecotypes of Lepidium meyenii Walpers (maca) was evaluated in three districts of the Junín province, Peru. In addition, the risk to human health due to exposure to heavy metals from maca consumption was evaluated. Soil samples and maca hypocotyls were collected in areas influenced by mining and metallurgical activity. The mean concentration of Cd (0.32 ± 0.23 mg/kg) and Pb (0.20 ± 0.12 mg/kg) in maca samples exceeded the values established by the Food and Agriculture Organization and the World Health Organization. The bioconcentration factor was less than 1. The estimated daily intake of each metal was below the oral reference dose. The hazard quotient and hazard index were less than 1, it is unlikely to cause non-cancer adverse health outcome. The cancer risk for As and Cd was higher than the tolerable limit (1 × 10−6) in children and adults. In the district of Ondores, the cancer risk for As in children was higher than the acceptable limit (1 × 10−4). Residents of the Ondores district would be more exposed to As and Cd from consumption of maca hypocotyls. It is very important to carry out continuous monitoring of other toxic metals in different ecotypes of maca (red, black, yellow, purple, creamy white, pink) in order to evaluate the variation in the accumulation of heavy metals and the level of toxicity of each metal between ecotypes. / Revisón por pares

La prédiction du transfert de cadmium du sol à la plante passe par l'élaboration d'un modèle décrivant la dynamique du métal dans le végétal. Cette thèse analyse les cinétiques d'accumulation du Cd dans Noccaea caerulescens, à l'échelle de la plante entière, de ses organes et au cours de son cycle de végétation. Elle cherche également à établir un modèle prédictif simple, fondé sur les relations entre concentrations d'exposition et en Cd dans la plante. Lorsque N. caerulescens est exposée à une concentration constante en conditions contrôlées, l'allocation de biomasse et la translocation du Cd aux parties aériennes sont constantes dans le temps. Une relation linéaire étroite existe entre la quantité de Cd prélevé, la biomasse et la concentration d'exposition, représentée par le facteur de bioconcentration (BCF). Le développement de la plante n'a pas d'effet sur l'influx racinaire en Cd, qui reste constant dans le temps et proportionnel à l'exposition. Ces résultats suggèrent que le Cd est alloué aux différents tissus aériens de la plante sans prédilection. A contrario, lors des cultures extérieures en terre, les concentrations en Cd, Ni et Zn diminuent au cours du temps après la vernalisation. Les trois métaux ont des comportements similaires en termes d'accumulation dans les différents tissus. La quantité maximale de Cd dans les organes aériens est observée à 2100°Cj. Lorsque la plante est en fleur, elle ne semble pas présenter d'organe aérien privilégié pour l'hyperaccumulation du Cd, les BCF étant constants dans le temps. L'utilisation du BCF permet une prédiction correcte des concentrations dans les parties aériennes, contrairement au modèle de Barber-Cushman / Prediction of cadmium transfer from soil to plant can be achieved by the development of a model describing metal dynamics in the plant. This thesis analyzes Cd accumulation and distribution kinetics in Noccaea caerulescens, in the whole plant and its organs during a growth cycle. A simple predictive model, based on the relationship between Cd exposure concentration and plant Cd concentration, is also developped. This work is based on long-term experiments in controlled conditions with a constant exposure and on outside soil experiments. When N. caerulescens is exposed to a constant concentration under controlled conditions, biomass allocation and Cd translocation to the shoots are constant over time. A strong linear relationship exists between the amount of Cd taken up, biomass and exposure concentration, represented by the bioconcentration factor (BCF). The plant development has no effect on Cd root influx, which remains constant during time and proportional to Cd exposure concentration. These results suggest that Cd is allocated to the various shoots? tissues without predilection. On the other hand, in the field, Cd, Ni, end Zn concentrations in shoots decrease over time after vernalization. The three metals have similar behaviors in terms of accumulation in the different tissues. The maximum amount of Cd in shoots is observed at 2100°Cdays. When the plant is in flower, no privileged shoots parts appear in Cd hyperaccumulation, the BCF is constant over time. The use of the BCF, measured in controlled conditions, allows a correct prediction of shoots concentrations, unlike the Barber-Cushman model

Submitted by Biblioteca de Pós-Graduação em Geoquímica BGQ (bgq@ndc.uff.br) on 2016-04-13T16:34:34Z No. of bitstreams: 1 JulianaRibeiroNascimento_DissertFinal.pdf: 1544852 bytes, checksum: f7b889157e7efc1834af5e11656509fa (MD5) / Made available in DSpace on 2016-04-13T16:34:34Z (GMT). No. of bitstreams: 1 JulianaRibeiroNascimento_DissertFinal.pdf: 1544852 bytes, checksum: f7b889157e7efc1834af5e11656509fa (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Universidade Federal Fluminense. Instituto de Química. Programa de Pós-Graduação em Geociências-Geoquímica. Niterói, RJ / A determinação de contaminantes em organismos é utilizada para avaliar o grau de poluição do ambiente em que vivem. A acumulação de metais, em um organismo marinho pode ser transferida diretamente ao homem ou através dos demais níveis tróficos superiores. O camarão–branco Litopenaeus schmitti é uma espécie de valor econômico ocorrente na baía de Sepetiba, região historicamente contaminada por metais oriundos da urbanização e das atividades industriais, principalmente metalúrgicas e portuárias. O objetivo deste trabalho é avaliar a concentração de Cd, Cr, Cu, Hg, Mn, Pb e Zn em camarões-branco da baía de Sepetiba. Os espécimes foram capturados por arrasto nas áreas interna e externa da baía durante período seco e chuvoso, utilizando o mesmo procedimento da pesca comercial, porém com tempo reduzido para 2 arrastos de 30 minutos cada. Machos e fêmeas foram identificados e o comprimento total foi utilizado para separar espécimes em estágio de vida juvenil (CT<110 mm) e adulto (CT>110 mm), tanto para machos quanto para fêmeas. A determinação de Cd, Cr, Cu, Mn, Pb e Zn em ICP OES e Hg no equipamento Lumex foi realizada para tecido muscular. As concentrações de Cd, Pb e Hg estiveram abaixo do limite de detecção, que são 0,02, 0,05, 0,005 μg/g, respectivamente. As maiores concentrações foram observadas para Cu e Zn, que variaram de 1.76 a 70.78 μg/g, e de 1.02 a 62.30 μg/g, respectivamente. As concentrações de Mn variaram de 0.38 a 7.96 μg/g, e as de Cr, de 0.08 a 1.76 μg/g. Apenas o Cr apresentou concentrações acima do limite estabelecido para consumo humano. A espécie não apresenta tendência geral de acumular metais em seu tecido muscular, mas correlações positivas com a biometria foram observadas para o Zn e para o Cr. O Mn apresenta correlações negativas com a biometria, sugerindo mecanismo de depuração deste metal. Diferenças significativas entre sexo foram observadas apenas para as concentrações de Cu, que em machos foram maiores que nas fêmeas, o que pode ser explicado pelas diferenças metabólicas entre sexos. Correlações significativas e positivas entre Cu e Zn ocorreram por se tratar de metais essenciais. O fator de bioconcentração (FBC) foi calculado utilizando dados secundários. Apenas o FBC do Cu foi superior a 1, entretanto é necessário cautela para interpretar este resultado como indicador de contaminação, já que o Cu é componente do pigmento respiratório de crustáceos. As diferenças de idade e tempo de exposição dos espécimes analisados foram normalizadas dividindo as concentrações de metais pelo peso seco. Esta abordagem evidenciou que o padrão de incorporação é maior em juvenis e adultos da área interna, mais próximos da fonte de contaminação, independentemente da sazonalidade e do sexo, ressaltando a importância da proximidade da fonte na assimilação de metais / Determine contaminants in organisms is useful to understand how impacted is the environment that they live. The metals accumulated in tissues of marine organisms can be directly transferred to humans or by the other trophic levels. The white shrimp Litopenaeus schmitti, economic explored species, occurs in Sepetiba Bay, which is contaminated by metals from urbanization; industrial activities, as metallurgical activities and sea harbor. The aim of this study is to evaluate the concentration of Cd, Cr, Cu, Hg, Mn, Pb and Zn on white shrimp from Sepetiba Bay. The specimens were caught by trawl in two sites (internal and external), during dry and rainy season, using the same procedure as commercial fishing, but during twice times of 30 minutes each. Males and females were identified and the total length was used to separate juveniles (TL < 110 mm) and adults (TL > 110 mm). The determination of Cd, Cr, Cu, Mn, Pb and Zn was performed to muscle tissue using ICP-OES, and Hg using Lumex. The concentrations of Cd, Pb and Hg were under detection limit (0.02, 0.05, 0.005 μg/g, respectively). The highest concentrations were observed for Cu and Zn, ranged from 1.76 to 70.78μg/g, and 1.02 to 62.30μg/g, respectively. The Mn concentrations ranged from 0.38 to 7.96μg/g and Cr from 0.08 to 1.76μg/g. Only the concentrations of Cr were above the limit for human consumption. The species has no general trend to accumulate metals in muscle tissue, but positive correlations with biometrics were observed for Cr and Zn. The Mn shows negative correlations with biometrics, suggesting depuration mechanism. No differences were observed evaluating males and females, except for Cu concentrations, explained by metabolic differences between genders. Positive correlations by Cu and Zn occurred because they are essential metals. The bioconcentration factor (BCF) was calculated using previous studies. The BCF of Cu was higher than 1, but caution is needed to interpret as an indicator of contamination, since Cu is the respiratory pigment of crustaceans. Concentrations of metals normalized by dry weight showed differences between age and season. The pattern of incorporation is greater in adults and juveniles from inner area, and it doesn’t depend on sex and season, showing that the assimilation is influenced by source of contamination

Des modèles prédictifs de prélèvement d’éléments traces métalliques (ETM) par des plantes hyperaccumulatrices sont à développer pour rendre la phytoextraction opérationnelle. Ce travail a pour objectif de développer, calibrer et valider un modèle biophysique combiné d’accumulation foliaire et de mise en solution du nickel lors de cultures de l’hyperaccumulateur Leptoplax emarginata sur un sol fertilisé et contaminé en Ni. Une partie de ce modèle intègre un facteur de bioconcentration lié à la transpiration (TSCF) qui caractérise le mode de transport principal du Ni à travers la racine et jusqu’aux feuilles, lors d’une cinétique couplée de production de biomasse foliaire et de transpiration. Sur des plantes intactes et transpirantes, nous avons déterminé un TSCFNi supérieur à 1 du fait : (i) d’une grande perméabilité des racines à la fois au nickel et à l’eau et (ii) d’un transport actif du Ni largement prédominant. A l’opposé, le TSCFNi du blé de Printemps, plante exclusive, était inférieur à 0,02, et le coefficient de réflection correspondant proche de 1, ce qui caractérise des racines perméables à l’eau mais quasiment pas au nickel. L’exceptionnelle capacité de L. emarginata à accumuler et à tolérer le nickel dans ses feuilles, et plus précisément dans ses épidermes, serait également attribuable à ses transpiration et production de protéines soufrées très élevées, tout particulièrement au niveau de ses feuilles les plus jeunes. Enfin, après avoir couplé notre modèle biophysique d’accumulation foliaire du nickel au modèle de mise en solution des ETM développé par Ingwersen et al. (2006), nous avons optimisé les paramètres du modèle, notamment les paramètres physico-chimiques, et avons validé notre modèle sur des données cinétiques conjointes de quantités de nickel accumulé dans les feuilles de l’hyperaccumulateur et de concentration en nickel dans la solution du sol. Les perspectives de ce travail sont (i) un approfondissement des relations entre l’accumulation foliaire du nickel (ou d’un autre ETM) par un hyperaccumulateur, la transpiration et la production de protéines soufrées permettant une complexation de l’ETM et (ii) une adaptation du modèle pour le terrain, ce qui nécessite notamment une meilleure utilisation du couplage production de biomasse foliaire/transpiration et une prise en compte des cinétiques d’humectation et de dessiccation du sol (équation de Richards de transport d’eau en conditions non saturées), ce qui conduira à la mise au point d’un modèle 1D (la profondeur du sol) d’accumulation foliaire et de mise en solution d’ETM / To make phytoextraction practically feasible, predictive models of metal uptake by hyperaccumulators need to be developed. The aim of this work was to design, calibrate and validate a biophysical combined model of nickel foliar accumulation and availability in soil solution during cultures of the hyperaccumulator Leptoplax emarginata on a fertilized and Ni-contaminated sandy topsoil. We succeed in this. Part of the model integrates a transpiration bioconcentration factor (TSCF) which characterized the main Ni transport through the root and to the leaves. We determined a TSCF value greater than 1 for L. emarginata, which was attributed to (i) a high root permeability to both Ni and water and (ii) a predominant Ni active transport. By contrast, Spring wheat was characterized by a TCSF value less than 0.02 and a reflection coefficient very near 1, indicating that its roots are permeable to water but quite unpermeable to nickel. The high capacity of L. emarginata to tolerate and accumulate Ni in their leaves should also be attributed to its large transpiration and sulfur accumulation, particularly in their youngest leaves. Perspectives of this work are (i) a detailed study on relations between Ni accumulation, transpiration and production of sulphur proteins and (ii) a field adaptation of the model taken into account water transport in unsaturated conditions, leading to design a combined 1D model of nickel foliar accumulation and availability in soil solution

Pollution of soil by trace metals has become one of the biggest global environmental challenges resulting from anthropogenic activities, therefore, restoration of metal contaminated sites needs due attention. The use of phytoremediation technologies as nature-based solution to pollution, could support successful implementation of green economic development strategies; with economically affordable and environmentally friendly benefits. The present investigation employed an exploratory study on the phytoremediation potentials of three selected native plants; Phytolacca dodecandra (L’Herit), Adhatoda schimperiana (Hochst) and Solanum incanum L, dominating areas close to heavy metal contamination sources; in metropolitan centers of Addis Ababa. In this work, concentration of six heavy metals of interest chromium (Cr), lead (Pb), cadmium (Cd), nickel (Ni) copper (Cu) and zinc (Zn) were examined in soil and in different tissues (leaves, stems and roots) of selected plants (both seedlings and mature plants), in dry and rainy seasons using atomic absorption spectrophotometer. Efficiency of phytoremediation is discussed based on calculated values of Bio-concentration Factor (BCF), Translocation Factors (TF) and Bioaccumulation Coefficient (BAC). Phytolacca dodecandra showed BCF, TF and BAC > 1 for Zn, Pb, Ni, Cu and Cd Adhatoda schimperiana gave BCF, TF and BAC > 1 for Zn, Cu, Ni and Cr; likewise, BCF, BAC and TF values of > 1 were noted in Solanum incanum for Zn, Cu, Pb and Ni. Based on these scenarios, the three plants could be utilized for phytoextraction of contaminated soil. Conversely, BCF and BAC for Cr levels in tissues of Phytolacca dodecandra were all < 1, which indicates unsuitability for phytoremediation of Cr in contaminated soils. Besides, Adhatoda schimperiana retained Pb and Cd in their roots showing root BCF > 1, while BAC and TF < 1, which highlights its suitability for phytostabilization. Moreover, BCF, TF and BAC values of < 1 noted for Cr and Cd in Solanum incanum reveal that Solanum incanum may not be a good candidate for remediation of Cr and Cd contaminated environments. In conclusion, results from this study revealed that the selected plants can accumulate substantial amounts of the above trace metals in their tissues and can serve as prospective phytoremediators of most of these metals. Phytoextraction and phytostabilization were the main mechanisms of remediation in this study. / Environmental Sciences / Ph. D. (Environmental Sciences)

MENVSC / Department of Ecology and Resource Management / South Africa is highly dependent on coal for production of electricity. The combustion of coal for electricity generation produces waste by-products which include fine ash (fly ash) and coarse ash. Fly ash (FA) is produced in large amounts while its utilization is low due to its classification as a hazardous material. Sasol produces about 7 million tons of FA, while Eskom produces about 28 million tons of coal FA annually. FA is a fine by-product from pulverized coal with detrimental effects on plants, soil or land, animals and human beings, and pollutes the air. The present investigation focuses on the examination of the chemical elements bioaccumulation and phytoremediation potential of Indian mustard (Brassica juncea) and Spinach (Spinacia Oleracea L). X-ray fluorescence (XRF) was used to analyze the elemental composition of FA and soil, Scanning Electron Microscope (SEM) to examine the morphology, while X-ray diffraction (XRD) analysis was used to evaluate the mineralogy of FA. The concentrations of metal and non-metal species that are released from FA on contact with water at different conditions were quantified using ICP-MS. Pot culture experiment was conducted to grow Brassica juncea and Spinacia Oleracea L. using FA and soil as growth medium. Leachates from the pots were collected and analysed using ICP-MS. Plant parts from harvested Brassica juncea and Spinacia Oleracea L. were cut separately and analysed using ICP-MS for the concentrations of different metal and non-metal species in plant parts. Plant parts were also used to estimate biomass and chlorophyll content (leaves). To prepare these plant samples for analysis, the powdered plant sample (0.5 g) was digested through aqua regia (HCL:HNO3 = 3:1 (v/v)) to near dryness using hotplate and filled to 100 mL of MilliQ water. The samples were filtered and directly used to determine the chemical elements concentrations. Blanks and internal standards were used for quality assurance during analysis. Chemical elements that are present in FA and sometimes in higher concentrations are associated with detrimental effects in plants, animals and human beings, hence phytoremediation is vital. Bioconcentration factor (BCF) was used to estimate the metal species accumulation ability of the plants from the FA, FA/soil mixtures, while translocation factor (TF) was used to assess the plant species potential for phytoremediation of coal fly ash dumps. Analysis of Varience (ANOVA) was used to statistically test data using Graphpad software package. Relationship between chemical elements in soil, FA and FA+soil growth media and also different plant parts (root, stem and leaf) of B. juncea and S. Oleracea L were calculated using the t - test, ANOVA-Bartlett test, Mann-Whitney Test and Kruskal-Wallis Statistic (KW) depending on each data set. The physicochemical characterization of coal fly ash showed that FA from Grootvlei power station can be classified as class F with an alkaline pH level of 10.62. It showed that particle morphology of this FA had a lower degree of sphericity with irregular agglomerations of many particles while there were dominant spherical particles and smaller sharp needle like particles. It is also an alumino-silicate material as confirmed by the high SiO2 and Al2O3 content, while soil leachates had an average/neutral pH of 7.22 with very high amounts of Si. In both soil and FA, elements that were expected to be readily available to plants included Ca, Si, K, Ba, Mo, Na, Al, Mg, Sr and non-essential elements (Si, Ba, Na, Al, Sr), which, if uptaken by plants’ roots can have negative impacts in plants. Physicochemical analysis of soil, FA and FA+soil leachates showed that the alkalinity of the FA changed over time and there was also a decrease in the EC due to dissolution iv of soluble major oxides, which was promoted by continuous water irrigation. The soil and FA+soil growth media showed similar results. Chemical elements like B, Mn, Fe and Ba were occurring at higher concentrations in leachates for most weeks in the pot culture experiments. However, it was observed that in the eleventh week of leachate collection all these chemical elements decreased to very low concentrations. This suggest that these chemical elements can be reduced over time as plants are being irrigated which is either due to uptake by plants or washed off with water. Statistically, there was a significant difference for different chemical elements of leachates from different growth media for each plant species (B. juncea and S. Olearcea L.). The overall growth rate shows that S. Oleracea L was better than that of B. juncea especially in the FA media over time, while the biomass of the two plant species showed similar results. After all, even though S. Oleracea L had carotenoid content below detection limits, it had higher chlorophyll b than B. juncea for all growth media in general. But, statistically there was no significant difference between the two plant species in terms of growth rate and biomass; even between the plant parts denoting similar growth performance for the two plant species under study. The bioaccumulation potential of the two plant species showed that chemical elements such as Fe, Mn, Ba, Zn and B were highly accumulated by the different parts of the plants. However, the chemical elements such as of Mo, Ni, Cu, and Cr showed the least concentrations. This trend was similar for all growth media and both plant species but this changes over time for different growth media and plant species as increasing and decreasing trends can be noticed. This led to no significant difference between plant species and also growth media, statistically. High BCF values of Fe, Mn, Ba, Zn and B were observed in the different parts of the plants for both plant species. However, Mo, Ni, Cu, and Cr had BCF values less than 1 for most growth media over time. BCF values in plant parts differed with time, growth media and plant species. Translocation of chemical elements shows that the B. juncea plant proved to be an effective phytoremediation plant species since it is effective in translocation of many chemical elements for different growth media to shoots while S. Oleracea L failed to translocate most chemical elements from stem to leaves although it translocated some from root to shoots. Hence, it can be concluded from the study that both species can be used in phytoremediation of coal fly ash dumps but with B. juncea being the most effective accumulator and translocator of many chemical elements. However, it can be recommended that chelating agents like ethylene diamine tetra acetic acid (EDTA) be introduced to solubilize chemical elements from growth media matrix into growth media solution to facilitate the quick transport of chemical elements into xylem, and increase

The continuity of the menace of mercury (Hg) is due to the continuous production and use of Hg and Hg containing products. Toxicity is just an outfall of use and exposure. Anthropogenic activities such as coal combustion and artisanal and small-scale gold mining have led to increasing Hg contamination and is the major source of Hg pollution into the environment that needs to be remediated. This study aimed to assess the phytoextraction capability of sweet sorghum (Sorghum bicolor) under different fertiliser treatments in Hg-contaminated soil. The potted experiment in a controlled environment included control S. bicolor and three phytoremediation treatments, i.e., Hg only; the addition of 4:1 green compost and; the addition of 0.2% NPK fertiliser. There were conspicuous signs of Hg phytotoxicity in plants with Hg only, namely wilting, senescent, inhibition of growth, and photosynthesis. There was stunted growth, but healthy plants observed in the treatment with the addition of green compost towards the end (day 60) of exposure. However, S. bicolor grew well until the last day of exposure in the treatment with the addition of 0.2% NPK fertiliser. Thus, this treatment showed the most effective phytoextraction potential of S. bicolor in Hg-contaminated soil. The effectiveness of S. bicolor in reducing the level of mercury was best assessed in the Hg bioavailable concentration in the spiked soil in which the Hg + NPK treatment has the lowest (0.77 mg kg−1). That resulted in the highest uptake (84.31%) percentage of Hg concentration recorded in the treatment with the addition of 0.2% NPK fertiliser compared to the other two treatments. The results suggest that the proportion of phosphate in the NPK fertiliser used, plays a huge role in the phytoextraction of Hg in the contaminated soil by S. bicolor. The Translocation Factor (TF) and Bioconcentration Factor (BCF), although higher within Days 20 and 40, was greater than 1 at the end of the exposure period suggesting a high probability that Hg was significantly transferred to the aerial parts of the plants. This is regarded as typical hyperaccumulator plant species. While S. bicolor was able to reduce the level of Hg in all three treatments, Hg + NPK treatment gave overall best results in physiological growth, the uptake, and reducing the level of Hg bioavailable in the spiked soil in terms of the effectiveness of phytoremediation method. / Environmental Sciences / M. Sc. (Environmental Science)