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Alterações fisiológicas em milho cultivado em solo com alto teor de cobre e submetido à aplicação de zinco / Physiological amendments in corn grown in soil with high content of copper and submitted to zinc applicationTiecher, Tadeu Luis 07 February 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Due to the historical application of cupric fungicides in vineyards, the amounts of copper (Cu) in these soils can reach levels that cause toxicity to plants. Recently researchers have tried alternative products to the cupric ones, in order to reduce the amount of Cu applied to the vineyards, which usually shows zinc (Zn) in its composition. This study aimed to evaluate the biochemical and physiological changes in corn plants, grown in soil with a high content of Cu and different levels added of Zn. In November 2011 the soil was collected from the 0-15 cm layer of a vineyard with high Cu content and in an area of native grass adjacent to the vineyard, with low concentrations of Cu and Zn, which served as treatment control, and both soils were classified as Typic Hapludalf. The experiment was performed in a greenhouse and was divided into two corn crops, the first between March and April, and the second between October and November, both in 2012. The treatments were the doses of 0, 30, 60, 90, 180 and 270 mg kg-1 of Zn added to the soil of the vineyard, plus the control treatment. Treatments had pH values in water and levels of available phosphorus and exchangeable potassium similar. At 35 days after emergence the plants were harvested and the accumulation of dry matter from roots and shoots and the concentration of Cu and Zn in leaves were determined. It was also evaluated the operation of the photosynthetic apparatus from the fluorescence of chlorophyll a and the photosynthetic pigments, biochemical parameters related to oxidative stress in leaves of plants, such as activity of superoxide dismutase (SOD) and of non-specific peroxidase (POD) were evaluated. The high concentrations of Cu and Zn in soil caused toxicity to corn plants and provided foliar concentrations above the levels considered normal in the leaves, from both cultivations. The Zn toxicity was evidenced by the decrease in the growth of both roots and shoots, as well as the induction of symptoms of toxicity and deficiency in photosynthetic parameters, reflecting photoinhibition. Moreover, it was observed oxidative stress and the antioxidant system of maize plants was not effective enough to reverse the condition of stress, especially in cultivated soils received higher doses of Zn. / Devido ao histórico de aplicação de fungicidas cúpricos em vinhedos, os teores de cobre (Cu) nestes solos podem atingir níveis que causam toxicidade às plantas. Recentemente tem-se buscado produtos alternativos aos cúpricos, com o intuito de reduzir a quantidade de Cu aportado aos vinhedos, os quais geralmente apresentam zinco (Zn) em sua composição. O objetivo foi avaliar se o aumento na concentração de Zn no solo poderia significar toxidez adicional às plantas de milho cultivadas, em um ambiente já contaminado com alto teor de Cu no solo. Em novembro de 2011 o solo foi coletado na camada de 0-15 cm de um vinhedo com alto teor de Cu e em uma área de campo nativo adjacente ao vinhedo, com baixos teores de Cu e Zn, o qual serviu como tratamento controle, sendo que ambos os solos foram classificados como Argissolo Vermelho. O experimento foi conduzido em casa de vegetação e foi dividido em dois cultivos de milho. O primeiro entre março e abril, e o segundo entre outubro e novembro, ambos no ano de 2012. Os tratamentos foram as doses de 0, 30, 60, 90, 180 e 270 mg kg-1 de Zn adicionadas ao solo de vinhedo, mais o tratamento controle, todos com valores de pH em água e teores de fósforo disponível e potássio trocável semelhantes. Aos 35 dias após a emergência as plantas foram coletadas e o acúmulo de matéria seca de raízes, de parte aérea e a concentração de Cu e Zn nas folhas foram determinados. Foi avaliado também o funcionamento do aparato fotossintético a partir da fluorescência da clorofila a e os pigmentos fotossintéticos, parâmetros bioquímicos ligados ao estresse oxidativo nas folhas das plantas, tais como atividade das enzimas superóxido dismutase (SOD) e das peroxidases não específicas (POD). Os teores elevados de Cu e Zn no solo causaram toxicidade às plantas de milho e proporcionaram teores foliares acima dos níveis considerados normais nas folhas das plantas, nos dois cultivos. A toxicidade de Zn se evidenciou através da diminuição no crescimento, tanto das raízes, como da parte aérea, bem como pela indução de sintomas de toxicidade e deficiência nos parâmetros fotossintéticos, refletindo na fotoinibição. Além disso, foi observado estresse oxidativo e o sistema antioxidante das plantas de milho não foi suficientemente eficaz para reverter a condição de estresse, especialmente nas plantas cultivadas nos solos que receberam as maiores doses de Zn.
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Parâmetros físico-químicos do efluente de ETE do distrito urbano de Montalvão/SP manejado com aguapé / Physico-chemical parameters of the effluent of the ETE urban district Montalvão / SP plied with water hyacinthSpósito, Thadeu Henrique Novais 09 August 2013 (has links)
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Previous issue date: 2013-08-09 / The research was conducted with the aim of obtaining information on the potential use of water hyacinth in cleaning the effluent of ETE district Montalvão, belonging to the municipality of Presidente Prudente/SP. For this, we evaluated some physical-chemical parameters of the effluent and the dry matter produced by plants. The experiment was conducted in a pond Wastewater Treatment Plant (ETE Montalvão) company SABESP. For the composition of the effluent treatments were originated from domestic ETE. The treatments were distributed in 25 cells (water tanks) with a storage volume of 0.25 m³ (250 liters) per cell. The treatments were characterized as follows: (T1) = 100% concentration in the effluent (raw final - discard); (T2) = 75% concentration in the effluent (dilution with water); (T3) Concentration = 50% wastewater (diluted with water), (T4) 25% = concentration of the effluent (dilution with water); (T5) = concentration of 100% of treated water. The parameters were determined according to CONAMA Resolution No. 430/2011 laying down the conditions and standards for effluent discharge into water bodies. The results were submitted to analysis of variance and mean comparison test F at 5% probability, and where relevant treatment effects were evaluated by applying the polynomial regression models. The best model to fit the data was selected based on the degree of significance of the coefficient of determination (R2). There was a development condition of the water hyacinth in any condition effluent preliminarily observed that some chemical parameters of the effluent were changed due to the presence of the water hyacinths and also that the water hyacinth is a vegetable filter that can be used as agents have been found phytoremediator there was an absorption of all the elements present in the effluent according to the concentration. / A pesquisa foi desenvolvida com o objetivo de obtenção de informações sobre o potencial de utilização do aguapé na limpeza do efluente de ETE do distrito de Montalvão, pertencente ao município de Presidente Prudente/SP. Para isso, foram avaliados alguns parâmetros físico-químicos do efluente e a massa da matéria seca produzida pelas plantas. O experimento foi conduzido em uma lagoa Estação de Tratamento de Efluentes (ETE Montalvão) da empresa SABESP. Para a composição dos tratamentos foram utilizados o efluente domestico originado da ETE distribuídos em 25 células (caixas d água) com um volume armazenado de 0,25 m³ (250 litros) por célula. Os tratamentos foram caracterizados da seguinte forma: (T1) = Concentração de 100% do efluente (bruto final - descarte); (T2) = Concentração de 75% do efluente (diluição com água); (T3) = Concentração de 50% do efluente (diluição com água); (T4) = Concentração de 25% do efluente (diluição com água); (T5) = Concentração de 100% de água tratada. Os parâmetros foram determinados de acordo com a Resolução CONAMA no 430/2011, que estabelece as condições e padrões de lançamento de efluentes nos corpos d água. Os resultados foram submetidos à análise de variância e ao teste de comparação de médias F ao nível de 5% de probabilidade e, quando pertinente os efeitos dos tratamentos foram avaliados aplicando-se os modelos de regressão polinomial. O melhor modelo para o ajuste dos dados foi escolhido em função do grau de significância do coeficiente de determinação (R2). Houve condição de desenvolvimento dos aguapés em qualquer condição de efluente, preliminarmente, observou-se que alguns parâmetros químicos do efluente foram alterados em função da presença do aguapé e também que o aguapé é um vegetal filtro, que pode ser utilizado como agente fitorremediador, foram constatado que houve uma absorção de todos os elementos presentes no efluente, de acordo com a concentração.
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Parâmetros físico-químicos do efluente de ETE do distrito urbano de Montalvão/SP manejado com aguapé / Physico-chemical parameters of the effluent of the ETE urban district Montalvão / SP plied with water hyacinthSpósito, Thadeu Henrique Novais 09 August 2013 (has links)
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Previous issue date: 2013-08-09 / The research was conducted with the aim of obtaining information on the potential use of water hyacinth in cleaning the effluent of ETE district Montalvão, belonging to the municipality of Presidente Prudente/SP. For this, we evaluated some physical-chemical parameters of the effluent and the dry matter produced by plants. The experiment was conducted in a pond Wastewater Treatment Plant (ETE Montalvão) company SABESP. For the composition of the effluent treatments were originated from domestic ETE. The treatments were distributed in 25 cells (water tanks) with a storage volume of 0.25 m³ (250 liters) per cell. The treatments were characterized as follows: (T1) = 100% concentration in the effluent (raw final - discard); (T2) = 75% concentration in the effluent (dilution with water); (T3) Concentration = 50% wastewater (diluted with water), (T4) 25% = concentration of the effluent (dilution with water); (T5) = concentration of 100% of treated water. The parameters were determined according to CONAMA Resolution No. 430/2011 laying down the conditions and standards for effluent discharge into water bodies. The results were submitted to analysis of variance and mean comparison test F at 5% probability, and where relevant treatment effects were evaluated by applying the polynomial regression models. The best model to fit the data was selected based on the degree of significance of the coefficient of determination (R2). There was a development condition of the water hyacinth in any condition effluent preliminarily observed that some chemical parameters of the effluent were changed due to the presence of the water hyacinths and also that the water hyacinth is a vegetable filter that can be used as agents have been found phytoremediator there was an absorption of all the elements present in the effluent according to the concentration. / A pesquisa foi desenvolvida com o objetivo de obtenção de informações sobre o potencial de utilização do aguapé na limpeza do efluente de ETE do distrito de Montalvão, pertencente ao município de Presidente Prudente/SP. Para isso, foram avaliados alguns parâmetros físico-químicos do efluente e a massa da matéria seca produzida pelas plantas. O experimento foi conduzido em uma lagoa Estação de Tratamento de Efluentes (ETE Montalvão) da empresa SABESP. Para a composição dos tratamentos foram utilizados o efluente domestico originado da ETE distribuídos em 25 células (caixas d água) com um volume armazenado de 0,25 m³ (250 litros) por célula. Os tratamentos foram caracterizados da seguinte forma: (T1) = Concentração de 100% do efluente (bruto final - descarte); (T2) = Concentração de 75% do efluente (diluição com água); (T3) = Concentração de 50% do efluente (diluição com água); (T4) = Concentração de 25% do efluente (diluição com água); (T5) = Concentração de 100% de água tratada. Os parâmetros foram determinados de acordo com a Resolução CONAMA no 430/2011, que estabelece as condições e padrões de lançamento de efluentes nos corpos d água. Os resultados foram submetidos à análise de variância e ao teste de comparação de médias F ao nível de 5% de probabilidade e, quando pertinente os efeitos dos tratamentos foram avaliados aplicando-se os modelos de regressão polinomial. O melhor modelo para o ajuste dos dados foi escolhido em função do grau de significância do coeficiente de determinação (R2). Houve condição de desenvolvimento dos aguapés em qualquer condição de efluente, preliminarmente, observou-se que alguns parâmetros químicos do efluente foram alterados em função da presença do aguapé e também que o aguapé é um vegetal filtro, que pode ser utilizado como agente fitorremediador, foram constatado que houve uma absorção de todos os elementos presentes no efluente, de acordo com a concentração.
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Stanovení toxických a esenciálních prvků v rostlinných materiálech / Determination of toxic and essential elements in plantsFilipčíková, Marcela January 2009 (has links)
The aim of diploma thesis is occurrence of toxic and essential elements in vegetables and fruit, especially in fruity baby food. The diploma thesis also dedicates processing of vegetables and fruit for production of baby food. Attention is direct to monitoring of baby food quality in the analytical aspects and also to legislative that is in this area. Samples for analysis are prepared using microwave mineralization and ICP-MS for detection. This is described in the experimental part of the diploma thesis.
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[en] ASSESSMENT OF THE MOBILITY OF ELEMENTAL CONTAMINANTS AND ENVIRONMENTAL IMPACTS DUE TO THE INAPPROPRIATE DISPOSAL OF FLUORESCENT LAMPS / [pt] AVALIAÇÃO DA MOBILIDADE DE CONTAMINANTES ELEMENTARES E IMPACTOS AMBIENTAIS DEVIDO AO DESCARTE INAPROPRIADO DE LÂMPADAS FLUORESCENTESLAIS NASCIMENTO VIANA 07 August 2023 (has links)
[pt] Embora as lâmpadas fluorescentes (LF) estejam sendo substituídas por LED
(diodo emissor de luz), a maioria das LF é descartada de forma inadequada e as
taxas de reciclagem ainda são, em geral, baixas (4 por cento na China, 5 por cento no Brasil, 7 por cento
no Canadá, menor que 10 por cento no Japão). Por causa da sua composição, as LF podem causar
um impacto ambiental significativo. Assim, no presente estudo empregamos
diferentes técnicas analíticas com o objetivo de caracterizar o material fosfórico
bruto de LF, quantificar os elementos mobilizados por soluções de chorume e chuva
ácida sintéticas, e avaliar os impactos ambientais relacionados ao descarte das
lâmpadas através de análise de ciclo de vida (LCA) para o cenário da cidade do Rio
de Janeiro. A análise do material bruto por fluorescência e difração de raios X (FRX
e DRX) aponta uma composição de fases sólidas complexa, com predominância de
Ca, P e Al, presença de elementos terras raras, As e outros. Através da extração
ácida auxiliada por micro-ondas, concentrações em massa de 0,1 até 16,5 por cento foram
encontradas para Al, Ba, Ce, Eu, La, Mn, P, Sr e Y no material bruto, e mais de 700
mg kg-1
de Hg. As lixiviações com as soluções sintéticas foram realizadas com e
sem agitação, partindo de 0,6 g de amostra, 1 mL das soluções, e 3 h de exposição.
O ensaio produziu a mobilização de diversos elementos com concentrações
atingindo 23,5 mais ou menos 0,4 mg kg-1 (Hg) na chuva ácida, e 34,0 mais ou menos 1,0 mg kg-1 (Sr) no
chorume. Devido à periculosidade de alguns elementos, as quantidades extraídas,
apesar de baixas, são preocupantes, e lixiviações consecutivas, comuns num cenário
real de descarte, podem agravar a situação. A análise de ciclo de vida apontou que
as lâmpadas geram maiores impactos ambientais nas categorias de ecotoxicidade
terrestre, toxicidade humana não-carcinogênica, potencial de aquecimento global e
esgotamento de recursos fósseis. A análise indicou que o aumento das taxas de
reciclagem pode reduzir em 70 a 90 por cento a maioria dos impactos ao meio ambiente. / [en] Although fluorescent lamps (FL) are being replaced by LED (light emitting
diode), most FL are disposed of improperly and recycling rates are still generally
low (4 percent in China, 5 percent in Brazil, 7 percent in Canada, less than 10 percent in Japan). Because of their
composition, FL can have a significant environmental impact. Thus, in the present
study, we used different analytical techniques with the objective of characterizing
the raw phosphor material of FL, quantifying the elements mobilized by synthetic
landfill leachate and acid rain solutions, and evaluating the environmental impacts
related to the disposal of lamps through life cycle analysis (LCA) for the city of Rio
de Janeiro scenario. The analysis of the raw material by fluorescence and X-ray
diffraction (FRX and DRX) points to a complex composition of solid phases, with
a predominance of Ca, P and Al, presence of rare earth elements, As and others.
Through microwave-assisted near-total acid extraction, concentrations varying
from 1 to 165 g kg-1 were found for Al, Ba, Ce, Eu, La, Mn, P, Sr, and Y in the raw
material, and more than 700 mg kg-1
of Hg. Leaching with synthetic solutions was
performed with and without agitation, with 0.6 g of sample, 1 mL of solutions, and
3 h of exposure. The test produced the mobilization of several elements with
concentrations reaching 23.5 more or less 0.4 mg kg-1
(Hg) in acid rain, and 34.0 more or less 1.0 mg
kg-1
(Sr) in landfill leachate. Due to the danger of some elements, the amounts
extracted, although low, are worrying, and consecutive leaching, common in a real
disposal scenario, can aggravate the situation. The life cycle analysis indicated that
the lamps generate greater environmental impacts in the categories of terrestrial
ecotoxicity, non-carcinogenic human toxicity, global warming potential and
depletion of fossil resources. The analysis indicated that increasing recycling rates
can reduce most impacts to the environment by 70 to 90 percent.
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Investigation of Potentially Toxic Elements in Agriculture Soil : Greenhouse and Open-field Farming in TürkiyeÖzkan, Furkan January 2023 (has links)
Greenhouse food production has intensive fertilizer practices, and it leads to contamination in the soil and food chains. This study investigated the potentially toxic elements (As, Pb, Zn, Cd, Cr, Cu, and Ni) (PTE) in agriculture soil and their bioaccumulation by dragon fruit and banana. Different fertility tests are conducted to see if there is a correlation between PTEs and fertilizers. CHNS/O analyzer was used to determine organic carbon and nitrogen concentration in the soil. Besides, organic and inorganic phosphorus amounts were analyzed to detect the amount of fertilizer input. Elemental analysis was conducted with ICP-MS. The amount of N, P, and K and PTEs compared and discussed to source the PTEs. Excessive fertilizer practices were acquired, and possible reasons and results were discussed. Besides, the investigations have revealed that concentrations of potentially toxic elements in greenhouse and open-field farms in Gazipaşa/Turkey are below the environmental standards in the soil and fruit samples. Organic farming practices are more dominant than inorganic farming practices in the sampling stations. / Seralarda yapılan gıda üretimi yoğun gübre uygulamalarına sahip olup hem toprakta hem de besin zincirlerinde kontaminasyona yol açmaktadır. Bu çalışma, tarım toprağındaki potansiyel olarak toksik elementleri (As, Pb, Zn, Cd, Cr, Cu ve Ni) (PTE) ve bunların ejder meyvesinde ve muzda olan biyolojik birikimlerini araştırmıştır. PTE'ler ve gübreler arasında bir korelasyon olup olmadığını görmek için farklı verimlilik testleri yapılmıştır. Topraktaki organik karbon ve azot konsantrasyonunu belirlemek için CHNS/O analiz cihazı kullanılmıştır. Ayrıca gübre girdi miktarının tespiti için organik ve inorganik fosfor miktarları analiz edilmiştir. Özellikle PTE tespiti için ICP-MS ile element analizi yapılmıştır. N, P ve K ve PTE'lerin miktarı, PTE'lerin kaynağını tespit edebilmek için karşılaştırıldı ve tartışıldı. Aşırı gübre kullanımı tespit edildi. Bu durumun olası nedenleri ve sonuçları tartışıldı. Ayrıca yapılan araştırmalar, Gazipaşa’daki sera ve açık tarla çiftliklerinde potansiyel toksik element konsantrasyonlarının toprak ve meyve örneklerinde çevre standartlarının altında olduğunu ortaya koymuştur. Örnekleme istasyonlarında organik tarım uygulamalarının inorganik tarım uygulamalarına göre daha baskın olduğu da tespit edilmiştir.
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Toxic elements in foodchain : exposure pathways to infants in selected areas of Limpopo ProvinceAli, Y.D. (Yemisi Deborah) 07 1900 (has links)
This study was concerned with establishing the extent to which various components of the environment were exposed to the three toxic minerals, arsenic, mercury and lead. The concentration of these three elements were determined in groundwater and surface water, soil, plants, animals such as goats, and humans in potentially contaminated areas in the Limpopo Province of South Africa. The focus of the study was to assess the possible exposure to infants through ingestion to arsenic, mercury and lead.
Comparison of the mineral content of water at the study sites with international and national drinking water standards, indicated water from Rooiberg, Leeupoort and Gravelotte are not fit for human consumption due to high arsenic and lead concentrations. Water at Gravelotte also has unacceptably high levels of mercury. The soil, plants, goat’s milk and mother’s milk at Rooiberg have higher levels of arsenic and lead than have been recorded for many other countries.
Mother’s milk and goat’s milk are the main sources of arsenic, lead and mercury contamination at Rooiberg. It is therefore newborns and toddlers who are most at risk from exposure to arsenic and lead.
This is a cause for environmental and health concerns, but as this research is only a base-line study, it is imperative that more comprehensive surveys of potentially toxic mineral contamination be conducted in the province. / Environmental Sciences / (M.Sc. (Environmental Science))
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Geochemical characterisation of gold tailings footprints on the Central Rand GoldfieldNetshiongolwe, Khathutshelo Emmanuel 05 1900 (has links)
Gold mining in the Witwatersrand Basin of South Africa has resulted in soil contamination due to the lack of sufficient environmental management plans for the tailings dumps and remnant footprints. Tailings reclamation as a strategy of reducing pollution in the Central Rand, for instance, has resulted in contamination of water systems by acid mine drainage (AMD). After removal of the tailings dumps, remnant material is left over on the tailings footprints and these contain significant amounts of pollutants that were initially in the tailings. Heavy rainfall during summer dissolves primary minerals and later in the dry season, secondary minerals are precipitated as efflorescent crusts on and nearby tailings dumps as well as footprints due to high evaporation. The efflorescent crusts can redissolve when it rains and form acidic, metal and sulphate-rich solutions due to their soluble characteristics.
This study aimed to characterise tailings footprints in areas targeted for human settlements and office spaces to assess their potential to release left over toxic elements such arsenic (As), lead (Pb), copper (Cu) and zinc (Zn). The approach to the study involved characterisation of oxidised and unoxidised tailings material and secondary precipitates on both tailings dumps and footprints. This involved determining the mineralogical composition using Powder X-ray Diffraction (PXRD). Dissolution and leaching studies were also conducted on the material followed by determination of constituent elements using inductively coupled plasma optical emission spectroscopy (ICP-OES) and sulphates using ion chromatography (IC). The leaching solutions used included rainwater; dilute sulphuric acid at pH of 3.0 (a common leachate in such acidic soils); as well as plant exudates such as oxalic and citric acids.
The leachate solutions were used to correlate the mineralogical composition of secondary precipitates and tailings footprints. Potential implications on humans following any accidental ingestion of the tailings or contaminated soils were assessed using gastric juices. The ecological risk factors and risk index together with the model to evaluate daily intake and different pathways to humans were used to assess the toxicity caused by exposure to contaminants in the materials. The experimental work was augmented by computer simulations based on geochemical modelling (using the PHREEQC geochemical modelling code) to determine the speciation of elements (and thus their potential lability and bioavailability), dissolution and formation of secondary mineral precipitates in the tailings dumps and footprints. The findings of the PXRD study showed that the mineralogy of the tailings and footprints was dominated by quartz (SiO2) and some minor minerals such as pyrite (FeS2), pyrophyllite (Al2Si4O10(OH)2), chlorite (Mg,Fe)3(Si,Al)4O10), mica (K(Mg,Fe)3 AlSi3O10(F,OH)2) while that of secondary precipitates was dominated by jarosite (KFe3+ 3(OH)6 (SO4)2), goethite (FeOOH), melanterite (FeSO4.7H2O) and gypsum (CaSO4.2H2O). Minerals obtained for the secondary precipitates were corroborated by geochemical modelling.
Leaching results using rainwater with pH ranges from 3.5 to 3.9 showed that trace elements are released very slowly from tailings dumps and footprints and in small concentrations during rainy seasons as follows: As (1.5 mg/L-4.5 mg/L), Pb (3.5 mg/L-5.5 mg/L), Cu (4 mg/L-4.8 mg/L) and Zn (23 mg/L-44 mg/L). The release and mobility of Cu, Pb, Zn and As occurs quite markedly when secondary precipitates dissolve, making the immediate impacted environment unfavourable for plant growth and any habits in the vicinity. This was substantiated by simulated dissolutions and assessment of the resulting elemental speciation that pointed to the elements being distributed in bioavailable forms, implying potential uptake by plants (such as vegetables that may be cultivated on such impacted soils).
The model was used to evaluate the daily intake and different exposure pathways and the results showed that children may daily intake 48.4 mg kg-1 day-1 and adults‟ 32.8 mg kg-1 day-1 . After 5 years (1825 days) of exposure more harm may be experienced and findings shows that kids are the most victims on these contaminated sites compared to adults. Both children and adults may absorb low levels of these toxic elements daily and after long time of exposure it may cause disease like cancer in their body which may lead to death. Pathways may be through inhalation and accidentally ingesting tailings soil that contain toxic elements. Drawing from the above findings, it will be important that tailings footprints that have been earmarked as land for development (residential or office space) be thoroughly assessed for potential release of toxic elements and high levels of acidity. Further reclamation aimed at reducing these hazards can then be implemented. / College of Agriculture and Environmental Sciences / M. Sc. (Environmental Science)
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Toxic elements in foodchain : exposure pathways to infants in selected areas of Limpopo ProvinceAli, Y.D. (Yemisi Deborah) 07 1900 (has links)
This study was concerned with establishing the extent to which various components of the environment were exposed to the three toxic minerals, arsenic, mercury and lead. The concentration of these three elements were determined in groundwater and surface water, soil, plants, animals such as goats, and humans in potentially contaminated areas in the Limpopo Province of South Africa. The focus of the study was to assess the possible exposure to infants through ingestion to arsenic, mercury and lead.
Comparison of the mineral content of water at the study sites with international and national drinking water standards, indicated water from Rooiberg, Leeupoort and Gravelotte are not fit for human consumption due to high arsenic and lead concentrations. Water at Gravelotte also has unacceptably high levels of mercury. The soil, plants, goat’s milk and mother’s milk at Rooiberg have higher levels of arsenic and lead than have been recorded for many other countries.
Mother’s milk and goat’s milk are the main sources of arsenic, lead and mercury contamination at Rooiberg. It is therefore newborns and toddlers who are most at risk from exposure to arsenic and lead.
This is a cause for environmental and health concerns, but as this research is only a base-line study, it is imperative that more comprehensive surveys of potentially toxic mineral contamination be conducted in the province. / Environmental Sciences / (M.Sc. (Environmental Science))
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Avalia??o da correla??o entre os par?metros, carbono org?nico total e elementos t?xicos, em solo de um posto de servi?o e revenda de combust?veis / Avalia??o da correla??o entre os par?metros, carbono org?nico total e elementos t?xicos, em solo de um posto de servi?o e revenda de combust?veisCoelho, Eduardo Philipp Medeiros 31 January 2011 (has links)
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Previous issue date: 2011-01-31 / Today a major responsibility for the contamination of soil and groundwater and surface water
are establishments known as gas stations of fuel which has attracted increasing attention from
both the general population as the state agencies of environmental control due to leaks in
storage tanks and mainly to disruption of pipe corrosion of tanks and pumping. Other
services, like oil changes and car wash are also causes for concern in this type of
establishment. These leaks can cause or waste produced, and the contamination of aquifers,
serious health problems and public safety, since most of these stations located in urban areas.
Based on this, the work was to evaluate soil contamination of a particular service station and
fuel sales in the city of Natal, through the quantification of heavy metals like Cd, Cu, Cr, Ni,
Pb, Zn of total organic carbon (TOC) and organic matter using different techniques such as
optical emission spectrometry with inductively coupled plasma source (ICP OES), Total
Organic Carbon analyzer and gravimetric analysis respectively. And also to characterize the
soil through particle size analysis. Samples were taken in 21 georeferenced points and
collected in the same period. The soils sampled in sampling stations P3, P5, P6, P10, P11,
P12, P13, P14, P15, P17, P18 and P20 showed the smallest size fractions ranging from fine
sand to medium sand. The other study sites ranged from fine sand to medium sand, except the
point P8 showed that only the type size medium sand and P19, indicating a particle size of the
coarse type. The small correlation of organic matter with the elements studied in this work
suggests that these are not of anthropogenic origin but geochemical support / Hoje um dos grandes respons?veis pela contamina??o do solo e ?guas subterr?neas e
superficiais s?o os estabelecimentos conhecidos como postos de revenda de combust?veis que
vem merecendo cada vez mais aten??o tanto da popula??o em geral como dos ?rg?os
estaduais de controle ambiental devido a vazamentos em tanques de armazenamento, e
principalmente ao rompimento da tubula??o de bombeamento e corros?o dos tanques. Outros
servi?os como, troca de ?leo e lavagem de autom?veis tamb?m s?o motivos de preocupa??o
neste tipo de estabelecimento. Estes vazamentos ou residuais produzidos podem causar, al?m
da contamina??o de aq??feros, graves problemas de sa?de e de seguran?a p?blica, visto que a
maioria destes postos localiza-se em ?reas urbanas. Baseado nisto, o trabalho realizado teve
como objetivo avaliar a contamina??o do solo de um determinado posto de servi?os e revenda
de combust?veis na Cidade de Natal, RN, por meio da quantifica??o de metais pesados como
Cd, Cu, Cr, Ni, Pb, Zn, do teor de carbono org?nico total (COT) e da mat?ria org?nica
utilizando t?cnicas distintas como espectrometria de emiss?o ?ptica com fonte de plasma
indutivamente acoplado (ICP OES), analisador de Carbono Org?nico Total e an?lise
gravim?trica respectivamente. E ainda caracterizar o solo por meio de an?lise granulom?trica.
As amostragens foram realizadas em 21 pontos georeferenciados e coletadas no mesmo
per?odo. Os solos amostrados nas esta??es de coleta P3, P5, P6, P10, P11, P12, P13, P14, P15,
P17, P18 e P20 apresentaram as menores fra??es granulom?tricas variando de areia muito fina
a areia m?dia. As demais esta??es de coleta variaram de areia fina a areia m?dia, exceto o
ponto P8 que apresentou somente granulometria do tipo areia m?dia e P19, indicando
granulometria do tipo grossa. A pequena correla??o da mat?ria org?nica com os elementos
estudados neste trabalho sugere que estes n?o sejam de origem antr?pica e sim de suporte
geoqu?mico
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