Die effek van swaarmetale by veriërende pH op lewerensieme en bloedstolling by Tilapia sparrmanii (Cichlidae)
- Authors: Gey van Pittius, Marina
- Date: 2014-07-23
- Subjects: Tilapia sparrmanii , Heavy metals - Environmental aspects , Water - Pollution , Speciation (Chemistry)
- Type: Thesis
- Identifier: uj:11777 , http://hdl.handle.net/10210/11501
- Description: M.Sc. (Zoology) , Tilapia sparrmanii (Smith) was exposed to sub-lethal doses of chromium, manganese, zinc and iron for 96 hours at an acidic pH (5), a physiological pH (7,4) and an alkaline pH (9), as well as a prolonged exposure (2 - 4 weeks) at an uncontrolled pH. In the laboratory fish were kept in aquaria which were supplied with continuously flowing borehole water. Controlled laboratory conditions existed during experimentation. Blood and liver samples of the experimental fish were sampled after exposure. The bioconcentration and the effect of the selected metals at the mentioned conditions, were thereby determined on bloodcoagulation, total and differential leucocyte counts, and liver enzYmes to investigate the possible damage to the liver. As metals have the ability to enter and concentrate in the body, the bioconcentration of each metal was determined by atomic absorption sPectrophotometry in the blood and liver. Chromium showed an increase in concentration in both the blood and liver, with an increase in pH after short term (96h) exposure. The statistical significant increases of manganese concentration in the blood over a short term were not reflected in the liver. It may be indicative of homeostatic control. A similar phenomenon was found with .zd.nc , The concentration of zinc in the liver did not reflect the progressive decrease in the blood wi th a increase in pH. Iron revealed a statistical significant increase in bioconcentration in the liver with, an increase in pH, which is indicative of the activity of the liver. The long term exposure of fish to chromium and manganese caused a significant increase in the concentration of the metals in the blood and liver. The only significant increase in concentration after exposure to iron, occured . in the Iiver. Exposure to zinc however caused a statistical significant decrease in concentration in both the blood and liver. Differential leucocyte counts reflected lymphocytosis, eosinophilia, monocytopenia and neutropenia, after short term exposure. These conditions nearly always resulted in leucopenia. Long term exposure to manganese and zinc reflected both eosinophilia and neutropenia. Chromium reflected eosinophilia, and iron, neutropenia. The only statistically significant change in the number of leucocytes after long term exposure, was caused by zinc and resulted in leucopenia. According to the photokymographic observation of blood coagulation by the thrombelastograph, exposure to the selected heavy metals lead to a prolonged clotting time and thrombocytopenia. Long term exposure (4 weeks) to manganese caused another bleeding disease, called hemophilia. It was thus evident that the exposure to heavy metals led to clotting defects, which caused bleeding.
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- Authors: Gey van Pittius, Marina
- Date: 2014-07-23
- Subjects: Tilapia sparrmanii , Heavy metals - Environmental aspects , Water - Pollution , Speciation (Chemistry)
- Type: Thesis
- Identifier: uj:11777 , http://hdl.handle.net/10210/11501
- Description: M.Sc. (Zoology) , Tilapia sparrmanii (Smith) was exposed to sub-lethal doses of chromium, manganese, zinc and iron for 96 hours at an acidic pH (5), a physiological pH (7,4) and an alkaline pH (9), as well as a prolonged exposure (2 - 4 weeks) at an uncontrolled pH. In the laboratory fish were kept in aquaria which were supplied with continuously flowing borehole water. Controlled laboratory conditions existed during experimentation. Blood and liver samples of the experimental fish were sampled after exposure. The bioconcentration and the effect of the selected metals at the mentioned conditions, were thereby determined on bloodcoagulation, total and differential leucocyte counts, and liver enzYmes to investigate the possible damage to the liver. As metals have the ability to enter and concentrate in the body, the bioconcentration of each metal was determined by atomic absorption sPectrophotometry in the blood and liver. Chromium showed an increase in concentration in both the blood and liver, with an increase in pH after short term (96h) exposure. The statistical significant increases of manganese concentration in the blood over a short term were not reflected in the liver. It may be indicative of homeostatic control. A similar phenomenon was found with .zd.nc , The concentration of zinc in the liver did not reflect the progressive decrease in the blood wi th a increase in pH. Iron revealed a statistical significant increase in bioconcentration in the liver with, an increase in pH, which is indicative of the activity of the liver. The long term exposure of fish to chromium and manganese caused a significant increase in the concentration of the metals in the blood and liver. The only significant increase in concentration after exposure to iron, occured . in the Iiver. Exposure to zinc however caused a statistical significant decrease in concentration in both the blood and liver. Differential leucocyte counts reflected lymphocytosis, eosinophilia, monocytopenia and neutropenia, after short term exposure. These conditions nearly always resulted in leucopenia. Long term exposure to manganese and zinc reflected both eosinophilia and neutropenia. Chromium reflected eosinophilia, and iron, neutropenia. The only statistically significant change in the number of leucocytes after long term exposure, was caused by zinc and resulted in leucopenia. According to the photokymographic observation of blood coagulation by the thrombelastograph, exposure to the selected heavy metals lead to a prolonged clotting time and thrombocytopenia. Long term exposure (4 weeks) to manganese caused another bleeding disease, called hemophilia. It was thus evident that the exposure to heavy metals led to clotting defects, which caused bleeding.
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Metal speciation by high performance liquid chromatography
- Authors: De Beer, Hannelie
- Date: 2014-11-25
- Subjects: Speciation (Chemistry) , Metals - Speciation
- Type: Thesis
- Identifier: uj:13108 , http://hdl.handle.net/10210/13083
- Description: Ph.D. (Chemistry) , Please refer to full text to view abstract
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- Authors: De Beer, Hannelie
- Date: 2014-11-25
- Subjects: Speciation (Chemistry) , Metals - Speciation
- Type: Thesis
- Identifier: uj:13108 , http://hdl.handle.net/10210/13083
- Description: Ph.D. (Chemistry) , Please refer to full text to view abstract
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Strategies of sample preparation for selected trace metal speciation and determination of pesticides in environmental samples
- Authors: Matong, Joseph Mojalefa
- Date: 2016
- Subjects: Speciation (Chemistry) , Trace elements - Speciation , Metals - Speciation , Metals - Environmental aspects , Pesticides - Sampling - Methodology
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/124963 , uj:20980
- Description: Abstract: Soil is an environmental constituent of the earth that performs a collection of essential purposes in our humanity such as food production. With fast industrial development and growth that have happened in most areas of the world during the recent years, the soil section is getting a large amount of persistent pollutants from different sources. These include trace metals and pesticides. An immense number in the scientific literature have been documented on the concentrations of trace metals and pesticides in soil. Contamination caused by agricultural activities such as pesticides and fertilisers is the main source of low soil and groundwater quality in many countries. Ineffective administering of agricultural processes can lead to contamination of soil and groundwater by nutrients and pesticides. For this reason, there is a need for the development of simple analytical techniques for motoring of these pollutants. Therefore, the main objective of the study was to develop sample preparation methods for the fractionation of trace elements and extraction of pesticides from environmental samples collected from different areas in Bloemfontein in the Free State. An ultrasound assisted sequential extraction procedure derived from a three-step Bureau Community of Reference (BCR) method was applied for fractionation of elements in three agricultural soil samples collected in geographical areas surrounding specifically Glen Agricultural College outside Bloemfontein (Free state Province, South Africa). The results obtained demonstrated that Mn, Co, Tl and Cd (except Soil 1) were found to have the highest percentage in the easily reducible fraction compared to other elements. Cu, Zn, Mo, Pb and Cd (in Soil 1) were dominant in the oxidizable fraction. Furthermore, the highest concentration of most metals such as Fe, Ni, V, Cr, Sb, Pb and As were obtained in the residual fraction of the soil samples. The environmental risks and degree of contamination were assessed using risk assessment code (RAC), individual contamination factors (ICF) and global contamination factor (GCF). According to risk assessment code (RAC) values, the soil samples demonstrated that Mn, Co, Ni, Zn, Mo and Cd pose a medium risk to the environment while Tl and Cd showed to high risk. In addition, individual contamination factors (ICF) were computed for each element and the highest ICF values (>10) were obtained for Cd and Mo. The global contamination factor (GCF) demonstrated that Soil 2 and 3 present the highest environmental risk compared to Soil 1... , M.Sc. (Chemistry)
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- Authors: Matong, Joseph Mojalefa
- Date: 2016
- Subjects: Speciation (Chemistry) , Trace elements - Speciation , Metals - Speciation , Metals - Environmental aspects , Pesticides - Sampling - Methodology
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/124963 , uj:20980
- Description: Abstract: Soil is an environmental constituent of the earth that performs a collection of essential purposes in our humanity such as food production. With fast industrial development and growth that have happened in most areas of the world during the recent years, the soil section is getting a large amount of persistent pollutants from different sources. These include trace metals and pesticides. An immense number in the scientific literature have been documented on the concentrations of trace metals and pesticides in soil. Contamination caused by agricultural activities such as pesticides and fertilisers is the main source of low soil and groundwater quality in many countries. Ineffective administering of agricultural processes can lead to contamination of soil and groundwater by nutrients and pesticides. For this reason, there is a need for the development of simple analytical techniques for motoring of these pollutants. Therefore, the main objective of the study was to develop sample preparation methods for the fractionation of trace elements and extraction of pesticides from environmental samples collected from different areas in Bloemfontein in the Free State. An ultrasound assisted sequential extraction procedure derived from a three-step Bureau Community of Reference (BCR) method was applied for fractionation of elements in three agricultural soil samples collected in geographical areas surrounding specifically Glen Agricultural College outside Bloemfontein (Free state Province, South Africa). The results obtained demonstrated that Mn, Co, Tl and Cd (except Soil 1) were found to have the highest percentage in the easily reducible fraction compared to other elements. Cu, Zn, Mo, Pb and Cd (in Soil 1) were dominant in the oxidizable fraction. Furthermore, the highest concentration of most metals such as Fe, Ni, V, Cr, Sb, Pb and As were obtained in the residual fraction of the soil samples. The environmental risks and degree of contamination were assessed using risk assessment code (RAC), individual contamination factors (ICF) and global contamination factor (GCF). According to risk assessment code (RAC) values, the soil samples demonstrated that Mn, Co, Ni, Zn, Mo and Cd pose a medium risk to the environment while Tl and Cd showed to high risk. In addition, individual contamination factors (ICF) were computed for each element and the highest ICF values (>10) were obtained for Cd and Mo. The global contamination factor (GCF) demonstrated that Soil 2 and 3 present the highest environmental risk compared to Soil 1... , M.Sc. (Chemistry)
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Chromium speciation analysis by ion chromatography coupled with ICP-OES
- Authors: Jansen van Vuuren, Samantha
- Date: 2012-09-04
- Subjects: Speciation (Chemistry) , Chromium , Ion exchange chromatography , Chromatographic analysis , Inductively coupled plasma spectrometry
- Type: Thesis
- Identifier: uj:3510 , http://hdl.handle.net/10210/6899
- Description: M.Sc. , The behaviour i.e. the distribution, bioavailability and toxicity of an element depends on the particular species in which it is present. That being said the prediction of the behaviour of species can therefore not be predicted by determination of the total concentration alone. Speciation analysis is thus an important process, which seeks to identify and quantify the species that occur in a sample. By identifying the species one is better equipped to predict the behaviour of the element if it were released into the ecosystem as well as if it were used in industrial processes. The speciation analysis of the dominant chromium species, Cr(III) and Cr(VI), has received much attention as these contradictory species are involved in many industrial processes such as plating and tanning for example. The species have opposing behaviour as Cr(III) is found to be a necessary micronutrient for mammals where as Cr(VI) is known to be toxic. Of the numerous methods developed for chromium speciation analysis, the on-line process of chromatographic preconcentration followed by simultaneous detection with a sensitive detector produces a synergistic effect for the successful speciation analysis of chromium. It was thus decided to study ion chromatography hyphenated with an ICP-OES as a means of studying chromium species. Anion chromatography coupled with ICP-OES was the basis for the development of the first method. Complexation of Cr(III) with EDTA to form a monovalent anion preceded its separation from Cr(VI) as the chromate anion. A carbonate-bicarbonate eluent was used to elute the species from a Dionex AG 9 guard column coupled with an AS 9 separation column. This method proved to be effective and fast, with each analysis taking less than two minutes. The second method was based on cation chromatography in the form of a Dionex CG12A guard column being coupled with an ICP-OES spectrometer as the detector. This method made use of a gradient elution program in which hexavalent chromium was eluted first with ammonium nitrate followed by trivalent chromium with nitric acid. This method was successfully applied to synthetic samples and was found to be effective.
- Full Text:
- Authors: Jansen van Vuuren, Samantha
- Date: 2012-09-04
- Subjects: Speciation (Chemistry) , Chromium , Ion exchange chromatography , Chromatographic analysis , Inductively coupled plasma spectrometry
- Type: Thesis
- Identifier: uj:3510 , http://hdl.handle.net/10210/6899
- Description: M.Sc. , The behaviour i.e. the distribution, bioavailability and toxicity of an element depends on the particular species in which it is present. That being said the prediction of the behaviour of species can therefore not be predicted by determination of the total concentration alone. Speciation analysis is thus an important process, which seeks to identify and quantify the species that occur in a sample. By identifying the species one is better equipped to predict the behaviour of the element if it were released into the ecosystem as well as if it were used in industrial processes. The speciation analysis of the dominant chromium species, Cr(III) and Cr(VI), has received much attention as these contradictory species are involved in many industrial processes such as plating and tanning for example. The species have opposing behaviour as Cr(III) is found to be a necessary micronutrient for mammals where as Cr(VI) is known to be toxic. Of the numerous methods developed for chromium speciation analysis, the on-line process of chromatographic preconcentration followed by simultaneous detection with a sensitive detector produces a synergistic effect for the successful speciation analysis of chromium. It was thus decided to study ion chromatography hyphenated with an ICP-OES as a means of studying chromium species. Anion chromatography coupled with ICP-OES was the basis for the development of the first method. Complexation of Cr(III) with EDTA to form a monovalent anion preceded its separation from Cr(VI) as the chromate anion. A carbonate-bicarbonate eluent was used to elute the species from a Dionex AG 9 guard column coupled with an AS 9 separation column. This method proved to be effective and fast, with each analysis taking less than two minutes. The second method was based on cation chromatography in the form of a Dionex CG12A guard column being coupled with an ICP-OES spectrometer as the detector. This method made use of a gradient elution program in which hexavalent chromium was eluted first with ammonium nitrate followed by trivalent chromium with nitric acid. This method was successfully applied to synthetic samples and was found to be effective.
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Application of magnetic nanocomposites for removal and preconcentration of trace metals in water
- Authors: Gugushe, Aphiwe Siyasanga
- Date: 2019
- Subjects: Speciation (Chemistry) , Trace elements - Speciation , Metals - Speciation , Nanostructures - Magnetic properties , Nanoparticles - Magnetic properties
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/292522 , uj:31790
- Description: M.Sc. (Applied Chemistry) , Abstract: Trace toxic metals have adverse effects on human health and the environment. Their concentrations should be monitored so that their levels do not surpass the levels put in place by the regulation committees for safety and health purposes. However, the determination and removal of these toxic metals from the environment is challenging because of the complexity of the real samples and low concentrations. Even with the sophisticated analytical techniques such as inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry, direct determination of trace metals in complex matrices is difficult. Therefore, simple, affordable and efficient methods are required for preconcentration of trace metals. In addition, multipurpose adsorbents that are reusable are needed for both removal and preconcentration processes. Therefore, the main aim of this work was to prepare or synthesise magnetic nanomaterials for the removal and preconcentration of toxic trace metals from environmental samples. In this study, different magnetic adsorbents were synthesized for the removal preconcentration of copper, manganese, nickel, arsenic, cadmium and for the lead and thallium. For the preconcentration of trace metals, solid phase extraction was the method of choice because it presented attractive advantages such as its simplicity, rapidness, efficiency, and cost-effectiveness. It can also be tuned for selectivity and specificity by incorporating specific functional groups. The structural and morphological properties of the adsorbent were investigated using X-ray powder diffraction (XRD), scanning electron microscopy/ energy dispersion x-ray (SEM/EDX) Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The quantification of the metal was achieved using inductively coupled plasma optical emission spectrometry. The first objective was to synthesize Fe3O4-ZrO2 nanocomposite functionalized with 3- aminopropyltriethoxysilane as a magnetic nanoadsorbent for removal of Cd(II), Cu(II), Mn (II) and Ni(II) ions from aqueous solutions, acid mine drainage effluents, wastewater and river water samples collected from different areas in Gauteng, South Africa. The adsorption data was assessed using different adsorption isotherms and adsorption kinetics. The data best fitted Langmuir isotherm and pseudo- second order kinetic models. The good feature about this adsorbent was that it was not highly affected by the sample matrix and could be reused up six cycles. It also displayed relatively high adsorption capacities for the...
- Full Text:
- Authors: Gugushe, Aphiwe Siyasanga
- Date: 2019
- Subjects: Speciation (Chemistry) , Trace elements - Speciation , Metals - Speciation , Nanostructures - Magnetic properties , Nanoparticles - Magnetic properties
- Language: English
- Type: Masters (Thesis)
- Identifier: http://hdl.handle.net/10210/292522 , uj:31790
- Description: M.Sc. (Applied Chemistry) , Abstract: Trace toxic metals have adverse effects on human health and the environment. Their concentrations should be monitored so that their levels do not surpass the levels put in place by the regulation committees for safety and health purposes. However, the determination and removal of these toxic metals from the environment is challenging because of the complexity of the real samples and low concentrations. Even with the sophisticated analytical techniques such as inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry, direct determination of trace metals in complex matrices is difficult. Therefore, simple, affordable and efficient methods are required for preconcentration of trace metals. In addition, multipurpose adsorbents that are reusable are needed for both removal and preconcentration processes. Therefore, the main aim of this work was to prepare or synthesise magnetic nanomaterials for the removal and preconcentration of toxic trace metals from environmental samples. In this study, different magnetic adsorbents were synthesized for the removal preconcentration of copper, manganese, nickel, arsenic, cadmium and for the lead and thallium. For the preconcentration of trace metals, solid phase extraction was the method of choice because it presented attractive advantages such as its simplicity, rapidness, efficiency, and cost-effectiveness. It can also be tuned for selectivity and specificity by incorporating specific functional groups. The structural and morphological properties of the adsorbent were investigated using X-ray powder diffraction (XRD), scanning electron microscopy/ energy dispersion x-ray (SEM/EDX) Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The quantification of the metal was achieved using inductively coupled plasma optical emission spectrometry. The first objective was to synthesize Fe3O4-ZrO2 nanocomposite functionalized with 3- aminopropyltriethoxysilane as a magnetic nanoadsorbent for removal of Cd(II), Cu(II), Mn (II) and Ni(II) ions from aqueous solutions, acid mine drainage effluents, wastewater and river water samples collected from different areas in Gauteng, South Africa. The adsorption data was assessed using different adsorption isotherms and adsorption kinetics. The data best fitted Langmuir isotherm and pseudo- second order kinetic models. The good feature about this adsorbent was that it was not highly affected by the sample matrix and could be reused up six cycles. It also displayed relatively high adsorption capacities for the...
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