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1

PULS, ROBERT WILLIAM. "ADSORPTION OF HEAVY METALS ON SOIL CLAYS (KAOLINITE, CADMIUM, MONTMORILLONITE, ZINC)." Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183889.

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Metal cation adsorption is the predominant chemical mechanism governing the attenuation of toxic metal movement in soils. Clay minerals are the primary adsorbent surfaces in soils due to their ubiquitous nature and large reactive surface area. This study examined the relative affinity of the metals cadmium, nickel and zinc for the clay minerals kaolinite and montmorillonite. The influence which different mineral adsorbents and different complexing ligands in solution have on the adsorption of metal ions was assessed using the Hard-Soft Acid-Base Principle as a theoretical framework for predicting the maximum extent of adsorption and rate of adsorption. The HSAB principle is that hard bases prefer to complex hard acids and soft bases prefer to complex soft acids. The hypothesis that initiated these investigations was that the hard-soft character of mineral surfaces is due to their surface functional groups and can be measured using metal cation adsorption selectivity experiments where pH and complex ion formation are controlled. When complex ion formation in aqueous solution was minimized (i.e. in Ca(ClO₄)₂), adsorption decreased in the order of decreasing softness, CD > Zn > Ni for both clay minerals. Montmorillonite behaved as a slightly harder Lewis base than kaolinite, sorbing the harder Ni and Zn ions to a greater extent than Cd, although both minerals behaved as soft Lewis bases. In the presence of chloride and sulfate ligands, adsorption sequences changed and reflected results from typical soil solution studies. In some cases the adsorption sequences can be explained using the HSAB principle together with computer speciation data and this approach merits further consideration and research. Adsorption over time and calculated adsorption rate constants were generally consistent with equilibrium selectivity data. Adsorption rates decreased in the order Cd > Zn > Ni in Ca(ClO₄)₂ for both clay minerals. The adsorption curves reflect a two-step adsorption process involving a rapid exchange-type reaction followed by a much slower adsorption involving diffusion into the crystal or alteration of the surface through the formation of a new solid phase involving the adsorbed ions.
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2

Whitt, Michael John-Ross. "Studies to Characterize Heavy Metal Content and Migration From Recycled PolyethyleneTerephthalate." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1350.

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Packaging Materials account for 31% of the world’s municipal solid waste. Agencies like the Environmental Protection Agency (EPA) and the Agency for Toxic Substances and Disease Registry (ATSDR) are pushing for the increased use of recycled thermoplastic materials. Polyethylene terephthalate (PET) is a commonly recycled thermoplastic which is used to package ready-to-eat fruits and vegetables. Most recycled polyethylene terephthalate (RPET) packaging materials contain heavy metal catalysts, the most common being antimony. The recent increased use of recycled plastic materials has been suspected as the source of increased human heavy metal exposure. In this study, cadmium, chromium, nickel, lead and antimony were quantified in post-consumer RPET rigid containers and films using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Two hundred samples were tested of which 29 were found to be contaminated with heavy metals in the parts-per-million (ppm) range. Chromium was found in all the contaminated sample replicates at an average level of 8.18 ppm. Cadmium was found in all the contaminated samples as well. Lead was found in 90.4% of the contaminated samples and concentrations ranged from a low of 0.02 ppm to a high of 0.36 ppm. Nickel was found in 96.4% of the contaminated samples while antimony was found in 97.6% of the samples. Due to limited sample material, 22 of the 29 contaminated RPET rigid containers and films were tested for heavy metal migration into a 5% citric acid:water solution (w/v) or deionized water. Samples were subjected to prolonged storage at 7.2 or 22.2°C for 1, 7 or 14 days, or were exposed for 5 minutes to microwaves from a 1700-watt microwave oven set to 70% power before analysis. Leachate values were at ppb levels but were often below the ICP-AES Limits of Detection which were at also the ppb level, whether calculated for deionized water or 5% citric acid in water. No measureable levels of heavy metal were detected for any sample exposed to water, regardless of treatment. For samples exposed to 5% citrate and stored or microwaved, only chromium and nickel leached at measurable levels, and the number of RPET’s releasing measurable chromium and nickel increased with microwaving compared to the same plastics stored at 22.2 or 7.2°C. Since leaching was calculated as µg/L of heavy metal lost from the entire inner surface (1021 cm2) of a retail salad bag, actual exposure to heavy metal would be much less than measured in this study as retail fruit and vegetable packages and microwaveable pouches usually contain very little liquid in order to increase food safety. The results therefore suggest the potential for little migration of heavy metal from recycled PET to whole or fresh-cut fruits and vegetables when held at ambient or refrigerated temperatures, or when microwaved.
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3

Gray, Brian David. "Acid volatile sulfides as indicators of heavy metal binding capacity in southeastern coastal sediments." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/20293.

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4

Mgobozi, Vuyokazi. "Heavy metal content absorption and medicinal potential of Egeria densa (Planch.) Casp." Thesis, University of Fort Hare, 2013. http://hdl.handle.net/10353/d1013121.

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The contamination of heavy metals in the environment is a looming concern worldwide. Egeria densa (Planch) (Submerged aquatic plant) from two ponds: Site A with co-ordinates (32º 48’22.04”S; 26°48’58.79” E) and Site B with co-ordinates (32°48’33.25”S; 26°48’33.25”S) in Alice (Eastern Cape) was evaluated for its ability to absorb heavy metals, phytochemical constituents, antimicrobial activity and ultra-structure using standard analytic procedures. Cadmium (Cd), copper (Cu), iron (Fe), lead (Pb), manganese (Mn), and zinc (Zn) were measured in water, sediments and plant. The concentrations of these metal elements were determined with use of Inductively Coupled Plasma- Optical Emission Spectrometry (ICP-OES). In sediments, the heavy metals (mg/kg) decreased in the order of their average concentration as follows: Fe (40.320) > Zn (1.259) > Pb (0.564) > Mn (0.186) > Cu (0.037) in Pond 1 whereas in Pond 2 Fe (61.527) > Cd (0.999) > Mn (0.648) > Pb (0.586) > Zn (0.156) > Cu (0.045). The highest concentration of Fe was detected in both sites and Cu being the least. The concentrations of the metals in the plants sample (from Pond 1) were found in order of Mn > Pb > Cu > Fe whereas cadmium and zinc were not detected, while the concentration in Pond 2 decreases in order of Zn > Mn > Pb > Cd > Fe > Cu. In the water samples, concentrations of heavy metals (mg/L) decreased in the order of their average concentrations as follows: Pb (35.36) > Fe (3.07) > Mn (0.238) > Cu (0.104), both cadmium and zinc were below the limit of detection in Pond 1, whereas in Pond 2 the concentrations decreased as follows: Pb (13.033) >Fe (1.69) > Cu (0.270) > Mn (0.248) > Cd (0.004) and Zinc was not detected. Phytochemical analyses of the plant extracts revealed the presence of phenols, flavonoids, proanthocyanidin, flavonols, saponins, alkaloid and tannins in all the extracts (water, acetone and n-hexane). Both acetone and water extracts, showed high concentration of proanthocyanidin, while tannin was the lowest in acetone extract. Antimicrobial evaluation using, Gram positive (Staphylococcus aureus, Bacillus pumilus, Bacillus cereus, Streptococcus pyogenes, Enterococcus faecalis) and Gram negative (Klebsiella pneumonia, Escherichia coli, Pseudomonas aeruginosa, Proteus vulgaris and Serratia marcescens) bacteria showed negative results for all the strain, except Streptococcus pyogenes which was inhibited at MIC of 0.1 mg/ml. Scanning electron microscopy (SEM) of ultra-structure of Egeria densa, showed that certain bacteria attached to the leaf, However more work has to be done on E. densa to verify the mechanism by which it accumulates heavy metals. The study shows that E. densa has a potential of accumulating heavy metals especial Manganese in plant.
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5

Allen, Tammy Reneé. "A classification of the dress of heavy metal music groups using content analysis /." This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-12042009-020120/.

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6

Pham, Vivian G. "Ecological Risk Assessment of Heavy Metal Content in the Hatillo River, Costa Rica." Scholarship @ Claremont, 2015. http://scholarship.claremont.edu/scripps_theses/571.

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Rivers all around the world have become increasingly polluted with heavy metals, largely due to industrialization and urbanization. Organisms exposed to high concentrations of heavy metals have shown evidence of biotoxicity and physical deformities. With biomagnification in mind, the possibility that this contamination may soon directly affect humans is a real concern, and policies in manufacturing industries worldwide may have to be reformed. In this study, we measured the concentrations of arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), and lead (Pb) in the Hatillo River and compared these values to those measured in the Tarcoles River, a highly polluted river, and Terciopelo Creek, a relatively clean river. The results showed that the Hatillo River had significantly lower levels of most detected heavy metals than both the Tarcoles and Terciopelo. Overall, sediments in all rivers showed high levels of heavy metal content--especially in chromium, copper, nickel, and lead--which could build up and affect organisms over a long period of time.
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7

Allen, Tammy Rene. "A classification of the dress of heavy metal music groups using content analysis." Thesis, Virginia Tech, 1993. http://hdl.handle.net/10919/46090.

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The research was a qualitative study of the dress of heavy metal (HM) music groups using content analysis. The purpose was to examine dress characteristics of a representative random sample of HM music groups. The objectives were (a) to develop a classification system for HM music groups based on time and subgenre, (b) to identify music groups within each cell (i.e., time and subgenre) of the classification system, and (c) to identify dress characteristics of a representative random sample of the music groups.

The subjects in the study were HM music groups as pictured on albums. The variables were the selected items of dress and the classification of the groups by time and subgenre. A classification system was developed and used for the selection of subjects. Using the HM Dress Classification Instrument developed by the researcher, specific dress characteristics of twenty-four HM music groups were identified. This data was compiled in tabular format.

Among the twenty-four HM groups, the predominant clothing was a black woven shirt and black leather/suede pants. Clothing trim included studs, motifs/designs, words and fringe. No visible jewelry was predominant. The primary shoes observed were western boots. Straight, shoulder-length black or blond hair with no head covering was predominant. Beards, makeup, tattooing, and other forms of corporal adornment were observed. Although some dress categories were dominated by single items, changes were observed across time and subgenres. The data indicated rejection of the two null hypotheses.


Master of Science
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8

Nkqenkqa, Vuyiseka. "Metal and microbial contamination of agricultural soil and the Veldwachters River, Stellenbosch, South Africa." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2423.

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Thesis (MTech (Environmental Health))--Cape Peninsula University of Technology, 2017.
Surface water is used as a source of water supply in many countries, including South Africa. One of the sources of surface water pollution is leachate and surface runoff from landfills. In agricultural soils, the landfill runoff and leachate deteriorate the quality and affect the fertility of soil. The entry of metals and microorganisms from landfill leachate to adjacent environments is through surface runoff due to rainfall. Adverse effects on human- and environmental health triggers a need to monitor and control contaminants in the environment. The aims of the study are to determine the effect of landfill runoff and leachate on agricultural soil and river water (Veldwachters River) running adjacent to the Devon Valley landfill site and to identify potential metal-tolerant organisms in environmental samples collected in Stellenbosch, Western Cape, South Africa. Samples (agricultural soil, river water and sediments) were collected once a month for a period of six months from the study area for analysis. Physicochemical parameters that are known to have major effects on environmental samples were assessed and the concentrations of various metals (Al, Pb, Cr, Mn, Mo, Co, Ni, Cu, Zn, Fe, Cd and V) were also determined by means of inductively coupled plasma mass spectrometry (ICP-MS). Soil texture analysis was tested in order to monitor the metal distribution in soils under the influence of environmental factors.
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9

Khandoker, Rafiqul Alam. "Distribution of Heavy Metals and Trace Elements in Soils of Southwest Oregon." PDXScholar, 1997. https://pdxscholar.library.pdx.edu/open_access_etds/4691.

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Soil samples from 118 sites on 71 geologic units in southwest Oregon were collected and analyzed to determine the background concentrations of metals in soils of the region. Sites were chosen in areas that were relatively undisturbed by human activities. The U.S. Environmental Protection Agency approved total-recoverable method was used to recover metals from samples for analysis. The twenty six metals analyzed were: Ag, AI, As, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, La, Li, Mg, Mn, Mo, Na, Ni, Pb, Sb, Se, Tl, V and Zn. The Klamath Mountains followed by the Coast Range contain the highest soil concentrations of AI, Ca, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Ni, V and Zn. Soils of the Coastal Plain and High Lava Plains contain the lowest concentrations of these metals. Unusually high soil As concentrations are found at two sites in the Klamath Mountains. All Be and Cd values above laboratory's reporting limits are also from the Klamath Mountains and Coast Range. Concentrations of soil Ba and La are fairly uniform throughout the region. Soil Pb levels are generally low with a few exceptions in the Klamath Mountains, Coast and Cascade Ranges. The region west of the Cascade Range has higher soil Hg contents than in the east. Soil metal concentrations are generally much higher in the region west of the Cascade Range, excluding the Coastal Plain, than in the east with the exception ofNa, because of more ultramafic rocks and a wetter climate. Soil metal concentrations are directly related to soil development with the highest concentrations being found in well developed Alfisols and Ultisols and the lowest concentrations in poorly developed Entisols. Most metals have similar averages and ranges of concentration compared to the rest of the United States (U.S.). Metals with high values compared to the rest of the U.S. are Cr, Co, Cu, Mn and Ni. In general, AI, Co, Cr, Cu, Fe, La, Li, Mg, Na, Ni, and V are concentrated in the B horizon while Ba, Ca, Hg, K, Mn, Pb and Zn are concentrated in the A horizon.
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10

Andrade, Marc-David. "Development of an on-site ex-situ unsaturated-flow remediation process for trace metal contaminated soils." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85117.

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Innovative means and methods were tested to develop an economical, pragmatic and environmentally sustainable soil remediation process for heavy metal contaminated soils. An unsaturated-flow soil washing procedure was devised to dissolve the soil-bound toxic heavy metals; the latter were extracted by a chemical washing solution that percolated through the soil matrix. Subsequently, the leached toxic heavy metals were selectively concentrated, by a chemical precipitation process, into a solid waste. Thereby, a fraction of the spent ethylenediaminetetraacetic acid (EDTA), within the washing and rinsing leachate, was theoretically regenerated and recycle-ready.
The unsaturated-flow washing procedure was perfected by applying different treatments to a soil from a secure landfill. This soil was contaminated with Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, S and Zn. The major contaminants were Fe, Pb, Zn, S, Cu and Mn, making up 25, 1.9, 1.0, 0.4, 0.4 and 0.2%wt of the soil. The extraction responses of the contaminants and those of Al, Ca, Mg and P were established for citric acid (0.5 M) and different molarities of diammonium EDTA ((NH4)2EDTA). The DOW Chemical Company supplied the (NH4)2EDTA (i.e. VERSENE), a 1.37M industrial cleaner, which roughly costs $1.85kg-1 in bulk. The affordability of VERSENE was a pre-condition for hoping to satisfy the economical feasibility of remediating trace metal contaminated soils.
Ultimately, the developed unsaturated-flow washing procedure was tested in a pilot-scale experiment, for its ability to remediate a soil from an abandoned car battery recycling facility. The latter soil was severely contaminated with Pb (3.9%wt). Drip irrigation was used to apply (NH4) 2EDTA and water-rinsing solutions to the surface of soil heaps that rested atop an impermeable barrier, which permitted the retrieval of the leachate. A cumulative EDTA input to the soil of 10.6% wt extracted 49.4% of the total Pb content of the soil. Alternatively, readily biodegradable citric acid barely extracted 2.2% of the total Pb content of the soil, for a cumulative input of 18.1% weight of soil. Different treatments were tested for their effectiveness in concentrating the leached toxic heavy metals into a solid waste. The Pb was best precipitated with Na2S alone, as it provided the most concentrated solid toxic waste.
The environmental sustainability of remediating trace metal contaminated soils was thoroughly examined, as per the amounts of chemical entrants and toxic waste by-products, and per the post-treatment leaching of toxic levels of the remaining and potentially toxic trace metals. (Abstract shortened by UMI.)
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11

Andong, Omores Raissa. "Spatio-temporal distribution of polycyclic aromatic hydrocarbons (PAHs) in soils in the vicinity of a petrochemical plant in Cape Town." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2432.

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Thesis (MTech (Chemistry))--Cape Peninsula University of Technology, 2016.
Polycyclic aromatic hydrocarbons (PAHs) are an alarming group of organic substances for humans and environmental organisms due to their ubiquitous presence, toxicity, and carcinogenicity. They are semi-volatile substances which result from the fusion of carbon and hydrogen atoms and constitute a large group of compounds containing two to several aromatic rings in their molecule. Natural processes and several anthropogenic activities involving complete or incomplete combustion of organic substances such as coal, fossil fuel, tobacco and other thermal processes, generally result in the release of the PAHs into the environment. However, the fate of the PAHs is of great environmental concern due to their tendency to accumulate and their persistence in different environmental matrices and their toxicity. Animal studies have revealed that an excessive exposure to PAHs can be harmful. Evidence of their carcinogenic, mutagenic, and immune-suppressive effects has been reported in the literature. In the soil environment, they have the tendency to be absorbed by plants grown on soil being contaminated by the PAHs. It is, therefore, important to evaluate their occurrence levels in different environmental matrices such as soil concentrations.
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12

Maleri, Rudolf A. "The ability of terrestrial Oligochaeta to survive in ultramafic soils and the assessment of toxicity at different levels of organisation." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/1200.

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Thesis (PhD (Botany and Zoology)) -- University of Stellenbosch, 2006.
Metals are natural elements of the earth crust usually present at low concentrations in all soils. Although many metals such as cobalt, copper, iron and zinc are essential to living organisms, at elevated concentrations most metals are toxic to organisms living in and on soils. Elevated concentrations of metals are caused either by anthropogenic deposition following remobilisation from the earth crust or are of natural origin. Ultramafic soils do not only pose unfavourable living conditions such as drought and poor organic content, these soils are also characterized by extremely high concentrations of a range of metals known to be toxic under normal circumstances. Ultramafic soils are of high ecological importance as a high proportion of endemic organisms, especially plants, live on these soils. As it is known that earthworms do occur in ultramafic soils, the aims of the present study were to investigate the abilities of earthworms to survive in these soils and the influences of elevated chromium, cobalt, copper, manganese and nickel levels. For the evaluation of the metal background conditions, soils originating from ultramafic rocks of the Barberton Greenstone Belt, Mpumalanga, South Africa were collected and different fractions representing different levels of bioavailability were analyzed for arsenic, chromium, cobalt, copper, manganese and nickel. To assess the mobile, readily available metal fraction, i.e. Ca2+- exchangeable metal cations, a 0.01 mol/L CaCl2 extraction was performed. To investigate the mobilisable metal fraction, representing the amount of easily remobilisable complexed and carbonated metal ions, a DTPA (di-ethylene-triamine-pentaacetic acid) extraction was conducted. In relation to non-ultramafic or anthropogenic contaminated soils, a far lower proportion of metals were extractable by the above mentioned extraction methods. To investigate the availability and effects of these metals on earthworms, two ecophysiologically different species were employed. Aporrectodea caliginosa and Eisenia fetida were long-term exposed to the ultramafic soils collected at the Barberton region and a control soil from a location at Stellenbosch with a known history of no anthropogenic metal contamination. The responses to the ecological stress originating in the ultramafic soils were measured on different levels of earthworm organisation. As endpoints affecting population development, cocoon production, fecundity and viability were evaluated. On individual level, growth, metal body burden and tissue distribution were investigated. As endpoints on subcellular level, the membrane integrity was assessed by the neutral red retention assay, the mitochondrial activity was measured by the MTT colorimetric assay and as a biomarker for the DNA integrity, the comet assay was performed. Focussing on manganese and nickel, the uptake by E. fetida of these metals was investigated with the exclusion of soil related properties using an artificial aqueous medium to draw comparisons to the uptake of these metals in natural soils. The possible development of resistance towards nickel was tested by exposing pre-exposed (for more than 10 generations) E. fetida specimens to ultramafic soils with concentrations of more than 4000 mg/kg nickel. The results showed that, except on the endpoint survival, which was less sensitive than all other bioassays, significant responses to the ultramafic challenge were observed in all earthworm bioassays and on all levels of organisation. The sensitivity of the responses of the earthworms towards the ultramafic conditions was not predictable by the level of organisation. The two species showed different strategies of metal elimination. In A. caliginosa, metals such as nickel, manganese and chromium were transported to the posterior section and the posterior section was subsequently pushed off by autotomization. In E. fetida, metals such as chromium and nickel were sequestered in storage compartments in the coelomic cells or fluid. Other metals, such as cobalt, were not taken up at elevated concentrations. Although an increased accumulation of nickel was observed in E. fetida specimens pre-exposed to nickel, development of resistance or cross resistance was not observed in this species. In contrast, pre-exposed specimen exposed to elevated concentrations of nickel showed a higher sensitivity in terms of survival, indicating the absence of acclimatisation or even genetic adaptation. A comparison of the two species employed indicated that A. caliginosa was less suited for the assessment of the ultramafic soils due to the high individual variation in metal body burden, the mass loss observed and the slow reproduction rate even in the control soils. This happened despite the fact that A. caliginosa was a soil dwelling species supposed to be better adapted to the soil substrate than the litter dwelling E. fetida. The toxicity of the ultramafic soils was not necessarily related to total or environmentally available amounts of the selected metals. Thus, it can be speculated that either these soils contained unidentified toxicants with resulting interactions between toxicants playing an important role or earthworms were able to remobilize metals occurring in these soils. As the singular application of an ecotoxicological endpoint did not give reliable results, especially seen over the duration of the exposures, it can be concluded that, when studying soils with such a complex composition, the utilisation of endpoints addressing different levels of organisation is necessary for the assessment of toxic stress emerging from these ultramafic soils.
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13

Xiong, Xianzhe, and mikewood@deakin edu au. "Heavy metal accumulation in soils at three field sites subject to effluent irrigation." Deakin University. School of Ecology and Environment, 2003. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20050902.110403.

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Three field sites were chosen to study the environmental assimilative capacity of heavy metals in soil. These sites were the Werribee Farm and the Myome Farm in Australia and Shenyang Zhangshi Irrigation Area in China. The Werribee Farm and the Shenyang Zhangshi Irrigation Area received sewage treatment and application on land for a long time. The Myome farm is an experimental site in which investigations on land application of municipal wastewater on water repellent soils is currently being trailed. Heavy metal contamination, in particular Cr, Cu and Zn, in the Land Filtration soil of Werribee Farm was widespread. More than a century of sewage irrigation has occurred in the Werribee Farm. The temporal distribution pattern of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) in the soil at this site follow an exponential trend with time and the spatial distribution pattern of accumulation of heavy metals in different paddocks correlates with the number of years of sewage irrigation at that site in the Farm. Extensive sewage irrigation at Shenyang Zhangshi Irrigation Area resulted in significant Cd pollution in soil-plant (rice) system and poses a significant threat to the health of local people. Even after eight years since cessation of sewage irrigation, the bioavailable fractions of Cd in the soil as analyzed by sequential extraction techniques were very high thus illustrating long-term persistence. The simultaneous competitive adsorption of metals in water repellent soils (at Myome Farm in South Australia) was studied. In the competitive situation, Cr, Pb and Cu are the heavy metal cations more strongly adsorbed by the soil, whereas Cd, Ni and Zn are the least adsorbed. The increase in Freundlich adsorption capacity by clay amendment suggested that clayed soils are capable sorption of higher heavy metal loadings compared to the non-clayed water repellent soil, which is more vulnerable to heavy metal inputs. A simple model of environmental assimilative capacity is proposed. The results of comparison of the three field sites shows that the Werribee Farm has a higher environmental assimilative capacity of heavy metals in soil than the soils at Shenyang Zhangshi Irrigation Area and Myome Farm, however heavy metal contamination at Werribee Farm is still a concern. The model of environmental assimilative capacity of heavy metals in soil is an effective tool to assist management of effluent applied land irrigation systems and can be used to better design environmental engineering systems.
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Li, Wai Chin. "Phytoremediation of heavy metal and PAH contaminated soil : effects of bacterial inoculation on PAH removal, metal speciation, bioavailability and uptake by Sedum alfredii." HKBU Institutional Repository, 2007. http://repository.hkbu.edu.hk/etd_ra/813.

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15

Sheldon, Bonita Joy. "Heavy metal uptake and accumulation in agricultural crops in urban areas of the Western Cape." Thesis, Cape Peninsula University of Technology, 2005. http://hdl.handle.net/20.500.11838/2006.

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Thesis (MTech (Physical Sciences))--Cape Peninsula University of Technology, 2005.
A research study into heavy metals in the Cape Town area, found significant amounts of potentially toxic metals such as lead, cadmium, chromium and iron leaching into the underground aquifer. A further additional study conducted on a community garden in Khayelitsha, showed that vegetable crops have the tendency to accumulate certain heavy metals if they are present in soil and water resources. This study was centered around the Philippi Horticultural Area, which is a large significant farming area within the Cape Metropolitan Region. The significance of the study lies in the fact that at least 50% of the local farmers' produce is sold directly to street traders, residents, local supermarket-chains and restaurants. The remainder of the produce is sold at the Epping Market. The purpose of this study was to investigate heavy metal accumulation in various vegetable crop species taken from some of the local farms in the Phillipi Farming area with the objective to: • investigate heavy metal accumulation in various vegetable crop species taken from some local farms in the Phillipi Farming area. • determine the concentrations of heavy metals present in water and soil resource since these will be the primary source of heavy metals to the vegetables. • determine the soil pH and soil organic matter as these two factors would determine the bie-availability ofthe heavy metals. • identify those crops that pose a definite health risk by means of comparing the determined results to the allowed limits.
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Ehsan, Sadia. "Simultaneous mobilization of polychlorinated biphenyl compounds and heavy metals from a field contaminated soil." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100355.

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A major factor complicating the cleanup at many sites is co-contamination by both organic compounds and heavy metals. Whereas much research has focused on the removal of either organic compounds or metals, relatively few studies have investigated simultaneous removal of organic and inorganic pollutants from soil.
The studies reported in this thesis have evaluated a novel technique for the simultaneous mobilization of polychlorinated biphenyl (PCB) compounds and heavy metals (HMs) from a field contaminated soil. Soil extraction with washing aids {surfactants/cyclodextrin in combination with chelating reagent(s)} was optimized for mobilization efficiency, recovery/recycle of washing additives, and in parallel detoxification of mobilized contaminants. PCB extraction efficiencies were determined with a method that converted all the PCB congeners to dicyclohexyl by hydrogenation over palladium. Studies demonstrated that 10 minutes of ultrasonic mixing of field contaminated soil with a combination of surfactant (30 mL L-1) or cyclodextrin (100 g L-1) and a sparing quantity (2 mmoles) of EDTA, simultaneously mobilized appreciable quantities of PCBs and most analyte metals (Cd, Cu, Mn, Pb, Zn, Ni, Cr).
Relative to individual reagents, combinations of surfactant (Brij 98, Triton X-301, or Triton XQS-20) or cyclodextrin (RAMEB or HPCD) with EDTA did not influence PCB extraction efficiencies perceptibly. The presence of surfactant or cyclodextrin in admixture with EDTA did not appreciably change the efficiency of mobilization of most heavy metals (Al, Cd, Cr, Fe, Mn, Ni, and Zn) but did increase the recovery of Cu and Pb with nonionic surfactant and cyclodextrin. When coupled with PCB removal by hexane back-extraction and precipitation of the HMs (mediated by hydrolysis of zero-valent magnesium (Mg0)}, aqueous washing suspension was regenerated and recycled twice to mobilize more contaminants from the soil. Three sonication-washes with the same charge of reagent mobilized appreciable quantities of PCBs (68 - 83%) and virtually all of the available Cd, Cu, Mn, and Pb and lesser amounts of the Zn (56%), Ni (59%), and Cr (50%) but only small quantities of Al (28%) and Fe (30%).
The release of EDTA from heavy metals complexes was efficient for most metals (99%) but was influenced by the nature of surfactant. EDTA recovery (62-65%) post three cycles of soil washing, hexane back-extraction, and Mg 0 treatment was similar for all reagent combinations. Among surfactants and cyclodextrin, only anionic surfactants suffered losses to Mg0 treatment.
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17

Taillon, Kate. "Modeling surface complexation relationships in forest and agricultural soil." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82435.

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The adsorption behaviour of trace metals in soil may provide us with a way to more accurately predict and assess the toxicity of metals in the environment. This thesis reports efforts to apply surface complexation modeling to agricultural and forest soil and to relate model parameters to common soil properties. This study considered Ca, Cd, Cu, Pb and Zn but the methods here could be applied to other metals. In Chapter 2, the surface charge and adsorption behaviour of a set of Ap horizons was characterised using back-titration and batch adsorption techniques. With the objective of simplifying the application of the NICCA model to surface charge and cation adsorption in whole soils the parameters of the NICCA model were related to soil properties (Chapter 3). Four of the six surface charge parameters could be predicted from soil properties and this enabled me to reasonably predict the surface charge of a second group of soils from soil properties. These results suggest that it is possible to make reasonable predictions about the surface charge and adsorption behaviour of a given type of soil using some easily measurable soil properties and a set of generic NICCA adsorption parameters for that soil type. In Chapter 4 this idea is applied to the determination of lime requirement for the agricultural soils.
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Kogoui, Kamta Frederic Noel. "Bioaccumulation and mixture toxicity of aluminium and manganese in experimentally exposed woodlice, Porcellio scaber (Crustacea, Isopoda)." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2677.

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Thesis (MTech (Environmental Health))--Cape Peninsula University of Technology, 2018.
Soil ecosystems in urban, rural and agricultural environments receive chemical input from diverse sources of contamination, such as wastewater, industrial discharge, agricultural and urban runoff, fertilizers, vehicle leakages, landfill seepage, and animal waste overspill. Agricultural activities, transportation and industrial activities are suspected to be the highest sources of metal contamination in Cape Town. Although scientists generally have a good understanding of the toxicity of individual chemical pollutants, there is a great need to bridge the gap between our understanding of the toxic effects of exposure to individual contaminants and those effects from exposure to mixtures of chemicals. Woodlice and other soil detritivores have a particularly important ecosystem function in mineralising organic matter. Woodlice experience stress when exposed to toxic levels of metals in the diet, which can reduce feeding rates and may combine with natural stresses to reduce fitness and lower 'performance', thereby possibly resulting in these organisms being unable to completely fulfil their ecological function. The objectives of this study were: to compare how aluminium and manganese are bioaccumulated in Porcellio scaber in terms of the contribution of the hepatopancreas in metal storage compared to the rest of the body; and to determine whether mixtures of aluminium and manganese affect each other’s bioaccumulation and distribution in Porcellio scaber. Woodlice collected from a clean field site (Kirstenbosch Botanical Garden) were experimentally exposed in the laboratory to a range of environmentally relevant aluminium and manganese concentrations. The woodlice were exposed to these metals in single and mixed metal experiments. Oak leaves, collected from a clean site, were contaminated with aluminium and manganese. Therefore, the woodlice were exposed via their food source. A control experiment, where oak leaves were not contaminated, was also prepared. At week 0 and after five weeks of exposure, a sample of the woodlice (5 per exposure group) were dissected to remove the hepatopancreas. Hepatopancreas and rest of the body samples were acid digested and analysed for the metals by means of the ICP-MS. Contrary to the existing knowledge of metals accumulating in the hepatopancreas of woodlice when ingested, this study showed a higher bioaccumulation of aluminium in the rest of the body of woodlice after 5 weeks of exposure than in the hepatopancreas. This result was interpreted as a possible detoxification mechanism by woodlice through the use of the exoskeleton during the moult cycle. A similar result was found when woodlice were exposed to mixtures of aluminium and manganese. This translated to the fact that woodlice were unable to effectively deal with the toxicity caused by the mixture of aluminium and manganese. In the group of woodlice exposed to manganese alone, it was found that manganese concentrations in the rest of the body of woodlice exposed for 5 weeks were statistically higher than the manganese concentrations in the rest of the body of woodlice at the start of the exposure (week 0). However, in the hepatopancreas, there were no statistical differences between the manganese concentrations in week 0 woodlice and the manganese concentrations in week 5 woodlice. Furthermore, manganese concentrations in the rest of the body of week 5 woodlice were statistically higher than manganese concentrations in the hepatopancreas of week 5 woodlice. This was interpreted as further proof that woodlice would accumulate certain metals (aluminium and manganese in this case) in their exoskeleton so that elimination can follow during the moult cycle.
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MacDonald, James Douglas. "The partitioning of Cd, Cu, Pb and Zn between the solid and solution phase of forest floor horizons in podzolic soils near metal smelters /." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85575.

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The emission of trace metals (TMs) into boreal forest regions of the northern hemisphere is an important environmental issue due to their potential detrimental impacts on these sensitive ecosystems. One of the foremost factors controlling metal cycling is the chemistry of the overlying organic forest floor of the forest soil. In this thesis we examine the chemistry of forest floor horizons of podzolic soils. Our goal is to improve our ability to predict the partitioning of metals between the soil solid and solution phases.
We developed a standard protocol to produce solutions that resemble lysimeter solutions from podzolic soils using air-dried samples. We hypothesized that the stabilization point of the electrical conductivity (EC) of the soil solution is indicative of the point in which soluble salts and organic material precipitated during sampling and storage are removed from the soil particle surfaces. Solutions produced by leaching the soils, once the EC of wash solutions had stabilized, were comparable to lysimeter solutions from the area where samples were collected with respect to the concentrations of divalent cations, pH, EC and dissolved organic carbon (DOC). The applicability of this procedure to trace metal partitioning in forest floors was explored. Laboratory extractions produced partition coefficients (log Kd) similar to observed lysimeter solutions ranging from 3.4 to 3.9 for Cd, 3.4 to 3.9 for Cu, 3.4 to 4.1 for Ni, 4.1 to 5.2 for Pb and 3.2 to 3.5 for Zn. According to a semi-mechanistic regression model based on observed lysimeter concentrations, the metal concentrations in solution were appropriate relative to known factors that influence metal partitioning in soils: pH, the concentrations of total metals and DOC.
While chemical characteristics of soils have been consistently observed to play important roles in the partitioning and toxicity of metals we wished to place the importance of the chemical characteristics of soil on mobility and toxicity in context. We interpreted field data that had been collected from transects established with distance from two point source emitters in Rouyn PQ, and Sudbury ON. Canada find developed equations that predict dissolved metal concentrations from total metal concentrations, soil pH, soil organic matter (SOM), and DOC contents. We integrated these equations into a simple box model that calculates changes in the concentration of metals in the organic and upper mineral horizons and includes a loop for vegetative return of metals to the forest floor.
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Ekumankama, Chinedu. "Effect of heavy metal co-contamination on the biodegradation of polycyclic aromatic hydrocarbons in an urban soil with high organic carbon content." Thesis, Northumbria University, 2015. http://nrl.northumbria.ac.uk/30323/.

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Biodegradation is a commonly used approach for the removal of organic contaminants from soil, relying on naturally present microorganisms that utilise the pollutants as an energy source. Often these sites are co-contaminated with heavy metals and the aim of the current research was to investigate how this affects the biodegradation of 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs), both in terms of removal rates and the overall functioning of the soil microbial community. Soil samples were obtained from a Greenfield site in Newcastle upon Tyne. The soil had a high organic content (11.0 %) and also contained elevated lead concentrations as a result of past atmospheric deposition from adjacent industrial activities. PAHs were applied to the soil using a coal tar source dissolved in acetone, giving a total PAH concentration in the spiked soil of 2166 mg kg-1. Individual PAH concentrations ranged from 1.44 mg kg-1 (acenaphthylene) to 325 mg kg-1 (benzo[b]fluoranthene); the benzo[a]pyrene concentration was 255 mg kg-1. The effect of heavy metal co-contaminants on the biodegradation was investigated using separate amendments of cadmium and lead to give respective total concentrations ranging from 133 to 620 mg kg-1 and 340 to 817 mg kg-1. Mercury amendment was used to give an abiotic control. The study was carried out over 40 weeks. For all treatments, the degradation of PAHs was observed to be biphasic. A novel kinetic model was developed to explain this dependence. In the absence of metal amendment, it was found that PAHs comprising two and three benzene rings generally degrade at a faster rate than four- five and six-membered rings. In the presence of metal amendments, overall % biodegradation after 40 weeks is relatively unaffected for two to four-ring PAHs but shows significant impairment for five and six-ring PAHs. Nevertheless, degradation rates generally decrease with increasing metal concentration, as do soil respiration rate, Shannon Diversity Index, and microbial biomass content. Lead appears to exert the greatest inhibitory effect. The novelty of this study arises from the integrated approach to investigating the effect of metal co-contaminants on the biodegradation of all 16 US EPA priority PAHs together with parameters relating to the functioning and diversity of the soil microbial community.
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21

Reeves, Alastair Ian. "Contaminant tracking through dendro-chemical analysis of tree-radii." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=69688.

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The research used dendro-chemical analysis of ash tree rings and current year leaf litter to track Cd, Pb, Zn, Cu, Mn, Cr, and Sn spread and cycling from a closed garbage dump-toxic waste site. This technique allowed for determination of areal extent, contaminant levels and time period of initial contaminant contact. Only Zn, Sn, and Cu were found in elevated quantities in the xylem wood and Pb in the leaf litter. Elemental concentrations of Pb, Sn and Cd in xylem wood and leaves of ash were positively correlated. Tin was the only element to demonstrate a clear initial contact period and elemental accumulation with age. Significant levels of Cu accumulated in the heartwood while Zn revealed significant but inconsistent accumulated patterns. Expected attenuation zones associated with municipal solid waste landfill leachate dispersion were not found; thus the pathway for contaminant dispersion was likely through groundwater flow.
An elemental index was developed to facilitate the use of dendro-chemical analysis in periods of suppressed tree growth resulting from environmental pollution.
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22

Hung, Grace Ann. "Metal accumulation in surface sediments of salt marshes in the Bay of Fundy." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=98728.

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One of the most recognised values of tidal salt marshes is the ecosystem service they provide as natural sinks for contaminants such as metals. This study examines net accumulation of metals (As, Cr, Cu, Hg, Ni, Pb, Zn and V) over a 5-yr period, from 1997 to 2002, in surface sediments of salt marshes in the Bay of Fundy, Canada. Metal accumulation has been measured in seven sites that extend from outer to inner Bay and in low and high marsh areas within each site. Overall, sediment metal concentrations are at or near their natural levels. Concentrations of metals show variability among marshes but are not significantly different between low and high marsh. Concentrations of As, Hg, Pb and V appear to be influenced by anthropogenic inputs. Calculated sediment loading rates for these metals generally showed gradients of increased loading from outer to inner Bay. Variability in sediment deposition rate is the driving force behind this spatial pattern. Results of this study suggest that the value of salt marshes as a sink for metals may be enhanced by high sedimentation rates.
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23

Kwok, Chun Kit. "Toxicological assessments of PAHs, OCPs and heavy metals in sediments at Mai Po and Deep Bay, Hong Kong." HKBU Institutional Repository, 2008. http://repository.hkbu.edu.hk/etd_ra/875.

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24

Henshel, Judy 1958. "Copper, manganese, and zinc in Puerco River sediments." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/276725.

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A study was conducted to test for the presence of heavy metals (Cu, Mn, and Zn) in surface sediments of the Puerco River channel in the aftermath of a toxic spill in 1979 near Church Rock, New Mexico. Analysis of samples from five sites downstream from the spill showed that these substances were not present in unusually large amounts, though an increasing gradient of metal concentration with distance downstream was revealed. Statistical analysis revealed the Cu, Mn, and Zn were associated with clay and silt, soil organic matter, organic carbon, and carbonates, all of which existed as extraneous, uncontrolled variables. Adjusted metal concentrations, obtained with covariate analyses, confirmed the increasing gradient downstream. Clay and silt also increased downstream. Some toxic substances may have leached into the riverbed; possible mechanisms for this process are also discussed and further study to substantiate or disprove this hypothesis is recommended.
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Clegg, Yolanda. "Historical inventory of sedimentary carbon and metals in a Bay of Fundy salt marsh." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30357.

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In 1996, four cores (∼30 cm depth) were extracted from the high marsh zone of Dipper Harbour salt marsh in the Bay of Fundy. Soil bulk densities are shown to be controlled by mineral density and are higher than those reported for salt marshes in the northeastern United States. Examination of variations in mineral content suggests that regular tidal action and ice rafting deposits the majority of the mineral sediment to the high marsh zone. Dating techniques (based upon pollen, 137Cs, 210Pb and total Pb) were applied to selected cores, suggesting accretion rates from 0.25 to 0.31 cm yr-1 which are higher than the rates of local relative sea level rise. Correlation of trace metal densities (Cu, Fe, Pb and Zn) to Al densities were used to justify Al normalization. After consideration of natural sources and adsorption factors, the normalized Pb profiles are shown to reflect historical pollution levels of leaded gasoline consumption. Carbon storage values in the upper 25 cm of sediment range from 7.3--10.5 kg C m-2 and carbon accumulation rates vary from 95 to 124 g C m-2 yr-1, representing 15--29% of the salt marsh macrophyte productivity.
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26

Aelst, Sébastien van. "Etude fonctionnelle des gènes plasmidiques de résistance au cuivre de Cupriavidus metallidurans: aspects physiologique, biochimique et écologique." Doctoral thesis, Universite Libre de Bruxelles, 2008. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210529.

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Cupriavidus metallidurans CH34 est la bactérie Gram négative considérée comme organisme-modèle pour l’étude de la résistance aux métaux lourds. Notre travail a porté sur sa résistance au cuivre, codée par les gènes cop du plasmide pMOL30. Ces gènes, responsables des différentes étapes de la résistance (compartimentation des systèmes d’efflux entre périplasme et cytoplasme, modification de valence, et d’autres fonctions totalement inconnues) ont suscité notre intérêt.

On distingue dans l’îlot cop des gènes codant pour des fonctions de résistance proprement dite (essentiellement par détoxication active du cytoplasme et du périplasme). En effet, les mutants de copSRABCD, copF, et dans une moindre mesure copJ et copE deviennent sensibles. Les phénotypes des mutants divergent toutefois suivant que la mutation soit sur un cosmide qui ne porte que l’îlot (pMOL1024) ou dans son plasmide d’origine (pMOL30). Un second groupe de mutants (copVTMK, copG, copL, copQ) se distingue par un phénotype plus résistant ou identique à la souche parente, sauf autour de la CMI. Ces gènes interviendraient donc à la CMI pour assurer la résistance la plus élevée et le maintien d'un état viable latent.

La présence de l’îlot cop permet de contenir le taux d’oxygène radicalaire qui reste à un taux basal lorsque les cellules sont adaptées au cuivre environnent. Après un choc de Cu (ou stress aigu), l’îlot cop répond de façon « explosive » au stress, en consommant l’énergie du potentiel membranaire et en augmentant fortement l’activité de la chaîne respiratoire.

La résistance au cuivre est inductible, mais de façon différenciée pour la souche sauvage (CH34) et celle qui ne porte qu l’îlot cop (AE1744) :la CMI de CH34 triple après adaptation au cuivre, alors que celle d’AE1744 est inchangée. Après un choc de Cu, la résistance au cuivre est plus fortement induite pour AE1744 que pour CH34. Ces observations suggèrent que l’îlot cop ait été sélectionné pour sa capacité à répondre à un stress aigu puis intégré dans un ensemble de gènes plus vaste qui répond à des impératifs de stress chronique.

L’analyse biochimique de CopI, une petite protéine bleue à cuivre, montre qu’elle porte un site analogue à celui des oxydases multicuivre. Son rôle pourrait dès lors être celui d’une réductase multicuivre. La protéine CopK lie de façon très spécifique le Cu(I) et il semble que la liaison du cuivre modifie sa structure. L’analyse écologique a montré que des homologues de copK pourraient être présents dans l’ADN extrait de la terre de biotopes chargés en cuivre, et dans les souches cuprorésistantes qu’on y trouve.

La contribution majeure de cette thèse est de montrer que l’effet d’un stress métallique ne se résume pas à deux états physiologiques « mort ou vif ». Il y a lieu de considérer des états transitoires (choc de Cu, adaptation au métal, survie autour de la CMI, persistance) où interviennent des gènes spécifiques dans un ou plusieurs états donnés. Les résultats biochimiques et physiologiques ne nous éclairent pas encore assez sur les interconversions Cu(I)/Cu(II) ni sur les flux de cations notamment vers l'espace extracellulaire. Cette thèse ouvre des perspectives sur des mécanismes (protection à la CMI, phénotype persistant) assurant la survie des bactéries ou leur potentiel de recolonisation lors d'une diminution de la pression toxique :les gènes copT, copV, copK, copM, copB, copG, copL et copQ semblent impliqués dans ces fonctions.


Doctorat en Sciences agronomiques et ingénierie biologique
info:eu-repo/semantics/nonPublished

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27

Souza, Lucas Anjos 1985. "Potencial fitorremediador de leguminosas herbaceas associadas a fungos micorrizicos arbusculares em solo contaminado com chumbo." [s.n.], 2010. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315654.

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Orientadores: Marlene Aparecida Schiavinato, Sara Adrian Lopez de Andrade
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-15T17:24:07Z (GMT). No. of bitstreams: 1 Souza_LucasAnjos_M.pdf: 3027770 bytes, checksum: b8bcb5d45029d8dc57eac08831f2233d (MD5) Previous issue date: 2010
Resumo: O desenvolvimento de novas tecnologias, para exploração do meio ambiente, está intimamente relacionado ao aumento da poluição ambiental, principalmente por metais pesados (MPs). O mais preocupante é quando a contaminação por MPs ocorre em solos agriculturáveis e leva, conseqüentemente, à contaminação de animais e seres humanos. O Pb é um MP que é cumulativo nos organismos vivos e não possui nenhuma função fisiológica vital conhecida até o momento. Esse elemento está presente em baixas concentrações quando o solo não sofreu influência humana. Existe uma grande preocupação em recuperar áreas contaminadas com MPs, mas diversas técnicas empregadas são muito laboriosas e caras. Uma alternativa seria a utilização da técnica de fitorremediação, na qual se utiliza plantas com capacidade de absorver e acumular grandes quantidades do contaminante em seus tecidos para, posteriormente, coletá-las e estocá-las em locais seguros. De uma maneira geral a associação de plantas com fungos micorrízicos arbusculares (FMA) altera a fisiologia da planta e dessa maneira o potencial fitorremediador pode ser acentuado. O objetivo desse trabalho foi investigar como a associação com o FMA Glomus etunicatum pode influenciar o crescimento e o potencial fitorremediador de Canavalia gladiata, Stizolobium aterrimum e Calopogonium mucunoides em solo contaminado com chumbo. Esse experimento foi conduzido utilizando-se as 3 espécies de leguminosas herbáceas citadas acima, inoculadas ou não com FMA, crescendo em diferentes concentrações de Pb (0, 250, 500 e 1000 mg kg-1) adicionado sob a forma de acetato de chumbo. Observou-se que a germinação das sementes de nenhuma das espécies estudadas foi afetada pelo Pb no solo. No entanto, o crescimento da parte aérea e das raízes foi afetado diferentemente em cada uma dessas plantas, sendo C. mucunoides a que sofreu mais com a presença de Pb no solo. A micorrização teve um papel importante na tolerância de C. mucunoides ao Pb, enquanto que nas demais espécies tal efeito não foi observado. A micorrização favoreceu o acumulo de Pb em C. mucunoides e em C. gladiata mas não em S. aterrimum. Todas as espécies estudadas apresentaram potencial fitoestabilizador de Pb; C. mucunoides apresentou menor translocação de Pb para a parte aérea que C. gladiata e S. aterrimum. A micorrização se mostrou fundamental apenas para o desenvolvimento de C. mucunoides na presença de Pb
Abstract: The development of new technologies, to the exploration of environment, is intimately related with the increasing environmental pollution, mainly by heavy metals (HMs). This scenario can become more serious when the contamination by HMs involves agricultural soils and results in contamination of crops used in human consumption and it lead to the contamination of animals and human beings. Pb is a HM that is accumulative in the living organisms and it doesn't possess any vital physiological function known until the present. This element is present in the soil in low concentrations when the soil hasn't suffered human influences. There is a great concern in recovering polluted areas with HMs, but several employed techniques are very laborious and expensive. An alternative would be the utilization of the phytoremediation technique that involves the use of plants with capability to absorb and accumulate great amounts of the pollutant in their tissues to, afterward collect and store them in safe places. In a general maner the association of plants with arbuscular mycorrhizal fungi (AMF) alters plant's physiology and, thus the phytoremediation potential can be enhanced. The objective of this work has been to investigate how the association with the AMF Glomus etunicatum can influence the growth and the phytoremediation potential of Canavalia gladiata, Stizolobium aterrimum and Calopogonium mucunoides in a soil contaminated with lead. This experiment was carried out using the 3 species of herbaceous leguminous mentioned above, inoculated or uninoculated with AMF, growing in different Pb concentrations (0, 250, 500 e 1000 mg kg-1) added as lead acetate. It was observed that the seeds' germination of all the studied species was not affected by Pb in the soil. However the growth was affected differently in each one of the species where C. mucunoides was the one that suffered more with Pb in the soil. The mycorrhization had an important role in the tolerance of C. mucunoides to Pb while in the other species we haven't observed such effect. The mycorrhization favored the accumulation of Pb in C. gladiata and in C. mucunoides but not in S. aterrimum. All the studied plants presented phytostabilization; C. mucunoides presented lower translocation of Pb to aerial parts than C. gladiata and S. aterrimum. The mycorrhization demonstrated it self fundamental only to the development of C. mucunoides in the presence of Pb
Mestrado
Biologia Vegetal
Mestre em Biologia Vegetal
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28

Klimek, Joanna. "Wpływ antropopresji na gleby obszaru Kotliny Grudziądzkiej." Rozprawa doktorska, Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy, 2019. http://dlibra.utp.edu.pl/Content/2353.

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Celem badań jest ocena wpływu antropopresji wywołanej funkcjonowaniem obiektów na gleby wybranego obszaru Kotliny Grudziądzkiej
The aim of the research is to assess the impact of anthropopression caused by the functioning of land for soils of the selected area of the Grudziądz Basin
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29

Ginnever, Rhoda C. "Soil and plant contents of lead and other trace elements with special reference to the influences of parent rock and pollution." Thesis, Aberystwyth University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324309.

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30

Matuszczak, Katarzyna. "Oddziaływanie zakładu celulozowo-papierniczego Mondi Świecie S.A. na wybrane elementy środowiska przyrodniczego (gleba i roślina)." Rozprawa doktorska, Uniwersytet Technologiczno-Przyrodniczy w Bydgoszczy, 2018. http://dlibra.utp.edu.pl/Content/1180.

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Celem badań było okreslenie, czy Zakład Mondi Świecie S.A może wpłynąć na otaczające środowisko przyrodnicze i wprowadzić potencjalne zagrożenia dla sąsiednigo obszaru oraz dla rozwoju flory na pobliskim terenie. Celem szczegółowych badań było określenie, który z badanych elementów środowiska był najlepszym akumulatorem pierwiastków
Research aim was to determine that Mondi Świecie S.A. can affect the surrounding environment and introduce a potential threat to the neighbouring area and for the development of flora. The detailed objective of the research was to determine which of the tested environmental elements was the best accumulator of the analysed elements
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31

Koliubakina, L. V. "Features of the content of serologic markers of neonatal sepsis in conditions of chronic contact with small doses of composition of heavy metals." Thesis, БДМУ, 2020. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/17670.

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32

Udeozor, Jude Onyeka, and Jude Onyeka Udeozor. "Application of Industrial Wastewater Effluent in Growth of Algae -- Effects of Heavy Metals on the Growth Rate, Fatty Acid and Lipid Content of Chlorella Sorokiniana and Scenedesmus Obliquus." Thesis, The University of Arizona, 2017. http://hdl.handle.net/10150/626388.

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Growing interest in biofuel production from non-fossil fuel sources has resulted in several studies exploring different raw material sources as feedstock, including many algae species, for large-scale production of biofuel. Algae are promising feedstock due to advantages such as its short growth cycle, high biomass production, and lipid content. However, there are still challenges to overcome in order to use algae for commercial biofuel production. One of these challenges is the requirement for a large quantity of water and nutrients needed for growing large quantities of the algae. This work explores a potential solution to this challenge by studying the possibility of using industrial wastewater to grow algae for biofuel production. However, many industrial wastewaters, including effluents from semiconductor processing plants, are known to contain heavy metals that are toxic to humans and the environment. In this work, the effects of four of such metals ions, As(V), As(III), Ga(III), and In(III) on Chlorella sorokiniana and Scenedesmus obliquus strains were studied. In particular, the heavy metal toxicity on the strains, effects on its growth rate, biomass yield, lipid content and fatty acid methyl esters (FAME) were studied. Also, the effect of controlling pH on growth rate, biomass yield, lipid content, and FAME was studied for Chlorella sorokiniana in the presence of Ga(III). The results of the study confirmed the toxicity of these metals on both strains. However, Ga(III) and In(III) had the highest effect, while As(V) showed the least toxicity to the strains, with Chlorella sorokiniana withstanding concentrations of As(V) as high as 140mg/L. The heavy metals were slightly more toxic to Scenedesmus obliquus compared to Chlorella sorokiniana. In addition, the heavy metals reduced the growth rate of both strains. High percent changes in growth rate (more than 50%) were seen in cultures containing Ga(III) and In(III). Furthermore, concentration measurements with Inductively Coupled Plasma Optical Emission Spectrometer (ICP) before, during, and at the end of the growth period, showed that Scenedesmus obliquus adsorbed higher amounts of the heavy metals compared to Chlorella sorokiniana. Microalgae biosorption of heavy metals limits its end use, hence making Scenedesmus obliquus a less favorable option for this study, but may be a better choice for wastewater treatment applications. The effects of the four metals on the lipid content and FAME profile of Chlorella sorokiniana were studied. The result showed an increase in Chlorella sorokiniana lipid content in the presence of In(III), but a decrease in the presence of As(V) and As(III). The heavy metals had effects on the strain’s FAME compositions. The fatty acid composition included C16:0, C16:1, C16:2, C16:3, C18:0, C18:1, ω-6, C18:2, ω-6, and C18:3, ω-3 accounting for more than 97% of the total FAME composition. Furthermore, controlling the pH of the culture in the presence of Ga(III) at 6.5 led to higher adsorption of the heavy metal, increase in lipid content, but no significant change in FAME composition.
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33

Bolle, Fabien. "L'impact des matériaux utilisés au contact alimentaire sur l'ingestion d'éléments chimiques dans l'alimentation humaine." Doctoral thesis, Universite Libre de Bruxelles, 2013. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209360.

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34

Leung, Pak-yip, and 梁柏業. "A brief review of the pharmacology of coriolus vesicolor (Yun Zhi) andthe determination of heavy metal contents in Yun Zhi products in HongKong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B43894525.

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35

Leung, Pak-yip. "A brief review of the pharmacology of coriolus vesicolor (Yun Zhi) and the determination of heavy metal contents in Yun Zhi products in Hong Kong." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B22763296.

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36

Bartos, Judith A. "Heavy metal distribution in Massachusetts soils /." 1994. https://scholarworks.umass.edu/theses/3444.

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37

Shyu, Guey-Shin, and 徐貴新. "Geostatistical Analysis of Soil Heavy Metal Content in Taiwan." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/05932430373587137367.

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博士
國立臺灣大學
農業工程學研究所
87
Geographic distribution of heavy metal content in soil reflects an important meaning for agriculture, water quality, and health. Therefore, the EPA of Taiwan has made a systematic study and investigation on soil contents of As, Cd, Cr, Cu, Pb, Hg, Ni and Zn in various regions of Taiwan. If the investigation results can be analyzed by appropriate scientific methodology, we then can come to an understanding of the pollution characteristics and spatial distribution and to appreciate more the value of this study. In the study, methods including factor analysis, ordinary kriging (OK), indicator kriging (IK) and multiple-variable indicator kriging (MVIK) were employed to analyze various sets of data in order to identify the pollution patterns and to delineate the range of contaminated sites. Results are shown using the tool of GIS. In the first section of this study, factor analysis method was used to study the major pattern of pollution in Taiwan. Three major factors from eight variable originally were found. Meanwhile, the cause of pollution was discussed. According to the survey results, the agricultural areas in Chang-Hua and Tai-Chung are most severely pollution. A possible reason could be that there were many plating factories in that area, and wastewater was discharge to rivers without appropriate treatment. Factor analysis method was employed to analyze the soil heavy metals content data of Chang-Hua county. Four common factors were extracted followed by ordinary kriging to estimate the spatial distribution of factor scores. Indicator kriging and multiple-variable indicator kriging were used to predict the probability distribution of heavy metal content excess the maximum allowable level (MAL). In the last section of this study, maps illustrating the geographic distribution of heavy metal in topsoil (0-15cm) horizons of Taiwan were developed using geostatistics and geographic information systems (GIS). We used variography, linear regression, and sensitivity analysis to characterize the spatial variability of heavy metal based on data from EPA. We used geostatistical interpolation, i.e., ordinar kriging, to estimate and map the total soil heavy metal content throughout Taiwan. The results showed that soils southwest of Taiwan tended to contain higher levels of As than average. Soils around Miao-li, Chang-Hua Tai-Chung, Kao-Hsiung Ping-Tung areas tended to contain higher levels of Hg than average. The resultant map depicted soils western of Taiwan having different characteristic. High estimate standard deviations occurred in the central mountain where data were sparse. The map will be useful in future research to determine the geographic distribution of heavy metal soils content, regional pattern of plant, genesis and topsoil geology, and in considering the consequences of land disposal of heavy-metal-laden wastes.
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38

Mangalgiri, Kiranmayi. "Heavy Metals in Glass Beads Used in Pavement Markings." Thesis, 2012. http://hdl.handle.net/1969.1/ETD-TAMU-2012-05-10966.

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Pavement markings are vital for safely navigating roadways. The nighttime visibility of pavement markings is enhanced by addition of retroreflective glass beads, most of which are made from recycled glass. Concern has been raised over the presence of heavy metals in glass beads used in pavement markings and their effect on human and environmental health. Based upon the potential risk associated with the presence of arsenic and lead in the glass beads, two Bills are currently being considered before the 112th Congress of the United States of America seeking to set a maximum permissible limit for the amount of arsenic and lead in glass beads used within pavement marking systems on domestic roadways. This study was designed to support legislative decision making by providing data necessary for risk assessment. The experiments carried out provide: an analysis of glass bead metal content and extractability; an evaluation of the relationship between arsenic content of the glass beads and their retroreflective performance; an evaluation of analytical methods used to measure the total bead metal content; and an analysis of samples of glass bead and soil mixture from a glass bead storage site used to determine site-specific metal concentrations in the soil media. Mean arsenic content, measured using the Pacific Northwest National Laboratory's KOH fusion digestion, in all the glass beads examined ranged from 11 ppm to 82 ppm, while mean lead content, measured using KOH fusion digestion, ranged from below quantification limit to 199 ppm. Total metal content measurements indicated a high amount of variability in the glass bead samples; most likely associated with the use of recycled glass feed during manufacturing. The relationship between the retroreflective performance and the arsenic content of the glass beads was analyzed and a weak but positive correlation was observed between the two factors. However, a more detailed study is required to evaluate the relationship between arsenic content and retroreflectivity. Different methods to evaluate the total metal content in glass beads were compared; it is recommended that any analytical method may be used, as long as the standard reference material is reproduced within the range of concentration expected in the glass beads. In the analysis of the field site samples of soil containing glass beads obtained from a glass bead storage and transfer facility, the mass content of beads in the soil varied from a mean of 19% to 78% depending on the location within the facility. However, a detailed analysis with larger number of samples must be performed to evaluate the effect of glass beads on the total arsenic content of the soil.
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39

藍梓文. "Investigation of the heavy metal content of commercially available herbal." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/84999936525037991683.

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碩士
國立新竹教育大學
應用科學系碩士班
102
Abstract   According to the market selling Polygonum multiflorum, Lonicera japonica, Semen ziziphi spinosae, Mentha, Spatholobus suberectus Dunn, Acanthopanax gracilistylus, Cinnamomum cassia Presl, Platycodon grandiflorum, Ephedra sinica, Schisandra chinensis, Prunus armeniaca, Cassia obtusifolia, Foeniculum vulgare, Crataegus pinnatifida, Morus alba, Pueraria lobata, Asparagus cochinchinensis, Angelica pubescens, Gentiana scabra, Terminalia chebula, Sterculia scaphigera, Citrus medica, Plantago asiatica, Ginkgo biloba, Glycyrrhiza uralensis, Cinnamomum cassia Presl, Lycium barbarum, Astragalus membranaceus, Citri Reticulatae, Perilla frutescens, and other 30 kinds of Chinese medicine through the microwave digestion pretreatment Inductively coupled plasma atomic emission spectrometer (ICP-AES), were detected in the digestive juice of Cu and Pb, of Zn, of Cd and Cr, Ni and Ag.   After microwave digestion pre-treatment sample analysis results, the traditional Chinese medicine used in this study, Cu, Pb, Zn, Cd, Cr, Ni and Ag heavy metals, Concentration range: Zn: 5.2ppm ~ 70.6ppm, Cu: <0.01ppm ~ 9.2ppm, Ni: <0.01ppm ~ 6.6ppm, Pb: <0.01ppm ~ 4.8ppm, Cr: <0.01ppm ~ 4.9ppm, Cd, Ag: <0.01ppm, in addition to this heavy metal Zn element values detected higher (for example,: for Semen ziziphi spinosae 70.6 ppm), the heavy metals concentrations were below 10 ppm.   Samples with the highest Cu containing Foeniculum vulgare; Cinnamomum cassia Presl with the highest Pb; Semen ziziphi spinosae with the highest Zn; Plantago asiatica with the highest Cr; Gentiana scabra with the highest Ni.
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40

Liu, Tung-Wei, and 劉東偉. "A Study On Heavy Metal Lead Content In Incineration Ashes." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/4zh522.

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碩士
國立臺北科技大學
環境工程與管理研究所
96
The waste in the incineration process produces 15 to 20 per cent of incineration ashes, which is a considerable impact and affect to the public. The research is investigates the large-scale refuse incineration plants around the Taipei County with 12 months incineration ashes characteristic studies that include bottom ash, fly ash and reacted ash in the incineration, and with discussions of composed ashes, lead content concentration, TCLP leaching concentration,with the nature of waste(including physical composition and chemical analysis). Under the incineration operation terms, the study is also focusing the process of regression to analyze the factor in the lead concentration, the heavy metal content characterization. According to results of the research, in the reacted ash, lead heavy metal content has the highest concentration of 1,343~3,918 mg/kg, at the average value of 2,809 mg/kg. 78 per cent of highest concentration distribution is found in the fly ash, and reacted ash, 22 per cent is found in the bottom ash. In the TCLP leaching concentration of lead, the bottom ash is controlled under the regulation of 5mg/L, but lead presents in the highest concentration at the fly ash and reacted ash respectively, that three results are higher than the control standard in the incineration heavy metal content regulation. The leaching rate of bottom ash is 3.11 per cent, the leaching rate of fly ash is 2.85 per cent, and the leaching rate of reacted ash is 3.09 per cent. The nature of the waste is consisted of plastics, food wastes, and leather-rubber in the regression analysis. The result to the food wastes is y=266.18x + 2176.5,R2=0.1539, that the result appears not significant positive relationship. In the incinerate combustion temperature section,Under high temperature conditions(919~1,028℃),lead reaction formed metal chloride(PbCl2 and PbCl4), the high burning temperature does affective to the fly ash and the reacted ash content concentration, the lead has small heat reaction with medium volatility of characteristic.As to the air combustion section, the high concentration of lead, the heavy metal is found in the fly ash(R2=0.228), that the result appears not significant positive relationship.
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41

Alajtal, Adel I., Howell G. M. Edwards, and Mohamed A. Elbagerma. "Monitoring of Heavy Metal Content in Tawargah Pond in Libya." Thesis, 2013. http://hdl.handle.net/10454/10411.

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Yes
The current study investigated the distribution of inorganic metals in the biggest reservoir in the neighbourhood of Misurata City, Tawargah Pond. The investigation was carried out during the topical periods of dry and wet season between August 2010 and January 2011. Levels of trace metals lead (Pb), copper (Cu), iron (Fe) and zinc (Zn)) were determined in the water samples taken. An atomic absorption spectrophotometer, Model 180-30 Hitachi, was used to determine heavy metal concentrations. The instrument was calibrated and standardized with different working standards. After making sure that the instrument was properly calibrated and results of the standard measurements were in the confidence limit, the concentration of metals in each sample was measured individually. High levels of lead and iron were found in water which indicates a possible contribution from the industrial activities and air pollution.
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42

Lin, Ya-Han, and 林亞翰. "Content of heavy metal in municipal solid waste in Kaohsiung city." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/19396459355916035691.

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碩士
國立高雄第一科技大學
環境與安全衛生工程研究所
102
This study used Kaohsiung City as its research subject. Two samples of regional waste were taken in different seasons in the months of April and July in 2013 from each individual waste management plant. These samples physical compositions were analyzed in order to understand the heavy metal contents in the combustible and non-combustible materials contained in the regional waste materials respectively, and to observe the effects of seasonal changes. The results of the analysis indicated that paper, plastics, and kitchen waste accounted for the majority of the volume in terms of physical composition, in both months, and in all districts. In 2013, combustible materials accounted for 95.59% of the weight of waste materials collected in Kaohsiung area, which indicated that more than 90 percent of the wastes collected in Kaohsiung area were combustible materials. The reason that metals and non-ferrous metals among non-combustible materials accounted for a smaller portion could very likely be that more valuable metals weretaken out to be recycled. A further analysis of heavy metal contents in the waste materials collected in Kaohsiung area indicated thatthe average contents of heavy metals ranked from the highest to the lowest were Pb>Zn>Cu>Cr>Cd. Among them, the average content of Pb was 147.84 mg/kg, and Cd was considered a trace metal in Kaohsiung area with an average content of lower than 1.00 mg/kg. The total contents of heavy metals between the Central District and Gangshan Waste Management Plants did not show significant differences. However, the total contents of heavy metals between the Renwu and Southern District Waste Management Plants did show significant variations between the two samplings, and the results matched those of the heavy metal contents of combustible materials. Because combustible materials accounted for more than 90 percent of the total amount of waste, the differences between the average total contents of heavy metals and the heavy metal contents of combustible materials were very small. The heavy metal contents from combustible materials in the waste from the four plants during the first sampling ranked from the highest to the lowest were Gangshan>Central District>Renwu>Southern District; and for non-combustible materials the rankings were Southern District>Renwu>Central District>Gangshan. Duringthe second sampling, heavy metal contents in the waste from combustible materials ranked from the highest to the lowest were Southern District>Renwu>Gangshan>Central District; and for non-combustible materials the rankings were Gangshan>Renwu>Southern District>Central District. Among them, the Southern District Waste Management Plant showed the most noticeable variations and had the largest percentage of combustible materials; therefore, it was concluded that heavy metal content in the waste was most significantly affected by combustible waste.
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43

Khunou, Letlhogonolo. "Soil, water and tissue heavy metal of communal sheep and the possible public health implications around the potentially polluted area of Khutsong, South Africa / Letlhogonolo Khunou." Thesis, 2012. http://hdl.handle.net/10394/14405.

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The present study was carried out to determine the levels of heavy metals, Arsenic (As), Chromium (Cr), Cadmium (Cd) and Lead (Pb) in samples of water, sediments, and specimens from sheep known to graze and drink from Wonderfontein stream around the Khutsong area in the North West Province of South Africa. Determination of heavy metal levels was carried out using Atomic Absorption Spectrophotometer. Abundance of metals in water samples followed the trend As>Pb>Cd>Cr, while that in sediments followed the trend: Pb>As>Cr>Cd. Faecal levels were highest for Cr, followed by Cd, As then Pb, while serum levels were highest for As, Cd Cr and then Pb. The metal concentration in liver, kidney and muscle showed the following trends respectively: As>Cd>Cr>Pb ; As>Pb>Cd>Pb and As>Cd >Cr> Pb. The liver, kidney and muscle samples had higher concentration of As compared to other heavy metals. Generally, most samples showed a higher concentration in As. The mean concentrations of heavy metals in ppm were compared with European Commission Regulation, World Health Organisation, Korean Soil Environmental Conservation Act and the Australian New Zealand Food Standards maximum acceptable levels. The metal levels generally tended to be higher than the permissible levels and thus, public health risks. A survey conducted also revealed that the community in Khutsong does not have the knowledge on environmental contamination due to mining effluents and the effects thereof. The varying levels of water and sheep specimen contamination with As, Cd, Cr and Pb revealed in this study imply public health risks. Further biomonitoring, public and animal health studies are therefore indicated in this area.
Thesis (Msc in Agric Animal Health) North-West University, Mafikeng Campus, 2012
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44

Zhou, Lixian. "Evaluation of the impact of contaminant on trace metal content of compost." Master's thesis, 2010. http://hdl.handle.net/10048/947.

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Thesis (M. Sc.)--University of Alberta, 2010.
Title from pdf file main screen (viewed on June 18, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Environmental Engineering, Department of Civil and Environmental Engineering, University of Alberta. Includes bibliographical references.
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45

Lee, Te-Chen, and 李德貞. "Analysis of Heavy Metal Content in Plastic Mobile Shell by ICP-OES." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/3my3gc.

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碩士
國立臺北科技大學
有機高分子研究所
97
Quantitative analysis of heavy metal content in plastic-based electronic products is an important issue because heavy metal is able to enter human body to cause various pathological change. In this work, Pb, Cd and Cr, three heavy metal frequently found in plastic mobile shell, are analyzed using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). Results from two common methods for sample pretreatment: microwave digestion and traditional hotplate digestion were compared and discussed in the thesis.
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46

HUANG, HUAI-DE, and 黃懷德. "Anti-inflammatory effects and heavy metal content of Ginseng radix residue extracts." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/taxrp4.

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碩士
國立宜蘭大學
生物資源學院碩士在職專班
107
Since ancient times, ginseng has been awarded the title of "King of the King of Medicine", and it is a precious medicinal material in the prescription of Chinese medicine. The composition and pharmacological mechanism of ginseng have been studied and discussed. Therefore, this study is mainly aimed at domestic Chinese herbal medicine. A large amount of ginseng drug residue is produced in the industry. The application of the drug residue to the animal feed requires consideration of the feeding properties of the animal. The analysis results show that the nutrient neutral detergent fiber (23.10±0.28%) and the acid detergent fiber (12.45±0.07%) )) Suitable for further development into feeding animals or as an additive. The anti-inflammatory analysis was carried out in the extract of the drug standard. In this study, the mouse anti-inflammatory response test was performed using mouse macrophage RAW264.7 as a test cell, and LPS-induced mouse macrophage RAW264.7 produced an inflammatory response when generated. A large amount of nitrogen oxidizing substances can determine whether ginseng slag can effectively inhibit the inflammatory effect of cells. The experimental results show that the ginseng drug extract is more effective than the ginseng raw material and the inflammatory reaction of only adding LPS to produce nitric oxide. The substance has more inhibition of inflammatory reaction, and the ginseng drug residue extract really affects the anti-inflammatory component and mechanism of action, and further analysis experiments are needed to explore the cause. To evaluate whether the ginseng drug residue extract still has the index component. In the determination of the ginseng raw material and the ginseng drug residue, the index component of the ginseng drug residue may still be analyzed. The ginsenoside Rg1 content of the index component is analyzed by HPLC, and the residual rate of ginsenoside Rg1 in the ginseng drug residue is found after analysis. Up to 43%, in the future can think about how to completely extract ginseng active substances. In addition, the content of heavy metals remaining in the dregs after boiling water was measured. For the changes of heavy metal content in different boiling times, the experimental results showed that the heavy metal content was not exceeded due to the change of boiling time, and all were within the national safety standards. The heavy metals of cadmium and copper are boiled for a long time, and the heavy metals are concentrated into the dregs. The analysis of zinc metal content will increase after boiling for 1 hour, and then the longer the boiling time, the ingredients will be free from the soup. The cause of the change in the results of heavy metal experimental analysis still needs to further explore the factors that should be affected.
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47

Lin, Hsiu-hua, and 林秀華. "Investigation of the heavy metal content and their contamination source in animals and plants." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/78517580436121173782.

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碩士
國立屏東科技大學
食品科學系
94
Turning animal muck into the organic compost is popular in recent years. Excessive minerals used in feed indirectly cause pollution to the environment. This research investigated the minerals and harmful heavy metal in animal (Poultry and aquatic products) and plant (wax apple and plant of short growth period) and its sources. The source of water, feed, animal manures, irrigation water, chemical fertilizer, plant burned ashes and clay were analyzed. The sample was digested to remove organic matter by the microwave nitrification, and used ICP/MS (inductively coupled plasma mass spectrometry ) to quantify Mn, Co, Ni, Cu, Zn, Cr , As, Cd, Pb, and Hg. In the standard testing, use more stable PE tube to preserve testing solution. The analysis results showed that the quantities of Co, Ni and Zn in turtle's viscera are higher than in meat. There is not obvious trend in the minerals and harmful heavy metal in the blood, meat, viscera of turtle among different size grades, but there had serious influence from minerals and harmful heavy metal in it’s water, sediment and feed. As quantity of turtle mixed feed sampled in the Gao-Shu had highest As among four places made the high As quantity in all parts of turtle. Quantity of As in the pool water is higher than Jiu-Ru and Chu-Ten. There are different minerals and heavy metal quantity in mixed types of farm fish. There had high quantity of the Zn in muscle and liver. Liver accumulated more Cu, Cd, As. Skin accumulated more Cr and Hg. Scale accumulated the Co. Gill accumulated the Ni, and more Mn, Zn, Pb in the fish bone. Zn is the major mineral in the liver of poultry, then Cu and Mn. Higher quantity of Cr, Co, Ni, Zn, Cr, Hg in duck’s feed, clay and pool water in Nan-Zhou than another three area tend to have higher deposition in all parts of duck. Three kind of vegetables, Cruciferae, Pak-choi, Arden lettuce showed the different effects in four kinds of experimental groups (blank, ashes, animal manure, chemical fertilizer), which Cr, Mn, Cu, Zn have the highest quantity in the soil, and Mn, Cu, content of Zn are relatively high in the plant. However, high quantity of Cr will not be absorbed by the tested vegetables. Minerals and harmful heavy metals contents are having the tendency to decrease along with gathering time. The Cu, Cd, Pb contents in the ashes are relatively high. The quantity of Cu, Cd, Pb in ashes group of three kinds of vegetables are also higher than other three tested groups. There are high quantity of Mn in the wax apple, then Cu and Ni. The Co and As, Cd, Hg are ND. Pb content is safe compared with quantity with standard (0.3 ppm) of National Health Administration. The quantity of Zn, Ni, Cu in the fruit is corresponded with analyzed values of the irrigate water. It will concentrate minerals and heavy metals in the burned ashes from branches and leaves. The animal manure containing minerals derived from undigested of feed and environment. The chemical fertilizer contains the minerals for plant growth. In conclusion, utilization of ashes, muck or chemical fertilizer need to be seriously controlled, in order to prevent the accumulating of harmful heavy metal in the environment for raising animals and plantation.
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48

Jeliazkova, Ekaterina A. "Assessment of aromatic, ornamental, and medicinal plants for metal tolerance and phytoremediation of polluted soils /." 2000. https://scholarworks.umass.edu/theses/3483.

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49

Pentz, Tarryn Susan. "Chemical characterisation of sediments and its correlation with the bioavailability of selected heavy metals." Thesis, 2012. http://hdl.handle.net/10210/6327.

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M.Sc.
The study looks into the sediment-bound metals (Fe, Mn, Cu, Cr, Cd, Co, Pb, Ni, Zn and Hg) of the Leeu/Taaibospruit catchment, which is impacted by agricultural, industrial and urban development. A number of chemical procedures, including total metal determination, the Tessier-sequential extraction scheme, the BCR Protocol, evaluation of the % TOC and determination of AVS to SEM ratios were applied to sediment samples collected from eight sites along the two rivers in the study area. Samples were collected during both high flow (summer) and low flow (winter) conditions. Following the chemical characterisation, bioaccumulation testing was conducted by exposing chironomid larvae to the sediment samples collected in from the study sites and determining their metal uptake relative to control specimens in uncontaminated sediments. These bioaccumulation results were then considered in conjunction with the chemical parameters in an attempt to identify any trends and correlations. Significant spatial and temporal differences were found in the metal concentrations from the study area. The total extraction results indicated that abundant amounts of Cr and Fe are present throughout the system. This was expected based on the make-up of the underlying geology. In addition, one of the sites, which is in close proximity to the town of Sasolburg, was identified as a potentially contaminated site. This site had significantly higher concentrations of Zn, Cu, Pb and, most notably, Hg when compared to the other sites. The elevated metal concentrations are most evident in samples collected under low flow conditions, but are also seen in the high flow Hg concentrations. Sequential extractions showed that Fe and Cr are concentrated in the residual phases of the sediment. Copper is largely present in the oxidisable fraction under low flow conditions, but also has considerable residual and reducible chemical forms. Manganese and Zn are distributed among all the different chemical phases and are therefore likely to be readily available for uptake by benthic organisms. The TOC was found to be highest during low flow conditions and at those sites with observable amounts of organic debris from the surrounding reeds and other vegetation. The AVS/SEM ratios were used to predict that due to the formation of insoluble metal sulphides, Cd, Cu, Hg, Ni, Pb and Zn are unlikely to be bioavailable at certain sites, i.e. the contaminated site 1 and at site 5, which only has agricultural impacts. In general, the bioaccumulation of Fe, Co, Ni, Cr and Mn was higher in the test larvae than the control larvae. Bioaccumulation of Cu, Pb, Zn and Hg levels were only higher than the control worms at sites where contamination was suspected to have taken place. Average bioaccumulation factors indicated that Hg is the metal that is most readily available for bioaccumulation, followed by Cu, Zn and Mn. All of these metals were bioconcentrated in the tissues of the test chironomids, while levels of Fe, Ni, Cr and Pb were found to be lower in the organisms than in the sediments. Although many of the chemical fractions were found to correlate significantly with the uptake of the different metals, the best overall correlation existed between the bioaccumulated metal and the total non-residual fraction. In fact, the sum of the first four steps of the Tessier-scheme correlated significantly with the bioaccumulated metal for all elements considered in the calculation, except for Pb. Additionally, the predictions made by the AVS model were found to be useful in justifying the behaviour and accumulation patterns of Hg, Zn and Cu at certain sites. The correlations and bioavailability clearly differed spatially, temporally and among the different elements. It is therefore suggested that prediction of the bioavailability and subsequent uptake of sediment-bound metals will require as many chemical and environmental factors as possible, and should include bioaccumulation and toxicity testing in order to examine the validity and completeness of these predictions.
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50

Huang, Chen-Hao, and 黃晨豪. "Multi-treatment Technologies for Removing Chloride Content, Heavy Metal and DXN of MSWI Fly Ash." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/t2n554.

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碩士
國立聯合大學
環境與安全衛生工程學系碩士班
102
Municipal solid waste incineration (MSWI) fly ash generated in Taiwan was mostly treated by cement solidification/stabilization and final disposed in isolated landfill sites. However, this method will increase fly ash weight, volume, and leaching risk of hazardous substance. Furthermore, fly ash can not be recycled and landfill space for solidified fly ash in Taiwan is gradually insufficient, thus facing and solving this problem are urgent and necessary. In this research, an M plant fly ash was studied for exploring multi-detoxification processes and some optimal processes were summarized and expected for future use. The results of process-I (i.e., P-1) of multi-water extraction experiment show that the relationship between L/S ratio and removal ratio of water-soluble chloride was positive; in contrast, heavy metal removal vs. L/S ratio was negative because of pH change. Additionally, heavy metal removal increased with the increase of water extraction time; an 80 °C thermal treatment could enhance both of the removals of water-soluble chloride and heavy metals. Long time ultrasonic treatment causing excessive fragment of fly ash resulted in more heavy metal leaching in TCLP test; nevertheless, short time ultrasonic treatment provide inadequate sonochemical reaction time. Therefore, proper ultrasonic treatment time benefiting TCLP-heavy metal was suggested. The optimal multi-water extraction experiment shows that water-soluble chloride decreased from 23.60% to 10.65% and mass loss was 30.43%, but TCLP-Pb failed TCLP test. In order to pass TCLP test, process-II (i.e., P-2) of gas stripping experiment was carried out. A best removal of water-soluble chloride was found at a ventilation of 30 L•CO2. Why the CO2 stripping can effectively remove water-soluble chloride of fly ash? It is proposed that CO2 can react with water to form CO32– in an alkaline fly ash slurry environment and further replace Cl– in fly ash, thus Cl– was released and removed. All of the TCLP-heavy metals was ND at a ventilation of 15 L•CO2; moreover, TCLP-Zn slightly increased and other TCLP-heavy metals were still ND at another ventilation of 24 L•CO2. The optimal gas stripping experiment shows that a CO2 ventilation of 15 L (0.072 L•CO2/g•fly ash), stirring speed of 150 rpm and L/S ratio of 5 could further decrease water-soluble chloride from 10.65% to 3.55% and all of the TCLP-heavy metals were ND; unfortunately, dioxins (1.54 ng I-TEQ/g) was higher than its regulatory limit (1.0 ng I-TEQ/g). Process-III to V of second CO2 stripping and thermal treatment experiments (i.e., P-3 to P-5) were consequentially conducted for further reducing water-soluble chloride and dioxins in fly ash. The results show that the second CO2 stripping reduced water-soluble chloride from 3.55% to 1.07%, and high temperature gave significant effect on dioxin removal, but minor effect on water-soluble chloride. Dioxins removal at oxygen-free environment was higher than that of aerobic environment at the same temperature. The results of process-IV and -V show that both of TCLP-heavy metals and dioxins were non-hazardous, and water-soluble chloride decreased to 3.20% and 0.71%, respectively. Finally, P-I to -V of fly ash M were applied to fly ash B and C sampled from B and C MSWI plants for verifying such processes applicability. Experimental results show that all of TCLP-heavy metals after each process of P-I to -V past TCLP test; in particular, water-soluble chloride reduced to less than 1% after P-III and P-V; additionally, thermal process for removing water-soluble chloride was insignificant―same as fly ash M. In conclusion, treatment technologies developed in fly ash M were applicable to other MSWI fly ashes.
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