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Investigation of waterborne cadmium toxicity in the green-lipped mussel, Perna canaliculus using biomarkers – a potential bioindicator of coastal metal pollution in New ZealandChandurvelan, Rathishri January 2013 (has links)
Coastal metal pollution is a major concern to the health and well-being of aquatic organisms. Bioindicator organisms such as mussels have the potential to monitor coastal metal pollution. In New Zealand, the feasibility of employing green-lipped mussels, Perna canaliculus as a bioindicator species is yet to be investigated. This thesis focuses on applying a suite of biomarkers on green-lipped mussels exposed to cadmium (Cd) to evaluate the utility of the biomarkers and investigate the utility of the mussels in assessment of metal pollution.
Cd is a non-essential metal and is known to be highly toxic to many aquatic organisms. This research consisted of a laboratory study to understand the mechanistic effects of Cd toxicity in green-lipped mussels. Physiological, biochemical, immunocytotoxic and cytogenotoxic biomarker responses were measured in mussels exposed to acute (96 h; 2000 µg L⁻¹ and 4000 µg L⁻¹) and subchronic (28 d; 200 µg L⁻¹ and 2000 µg L⁻¹) Cd treatments. The 96 h LC₅₀ value for P. canaliculus was 8160 µg L⁻¹, indicating that the green-lipped mussels were relatively tolerant to Cd exposure.
Results from the Cd exposures, indicated that Cd had a negative impact on physiological processes such as feeding and oxygen consumption. Cd-induced physiological impairments caused an imbalance between energy gain and energy loss in the mussels that led to negative scope for growth. Detoxification (metallothionein-like protein) and defence mechanisms (catalase) were induced in the mussels to provide protection against the toxic effects of Cd. However, the defence mechanisms were not sufficient to protect the mussels from damage due to lipid peroxidation. DNA damage was also observed in the haemocytes of mussels as a result of Cd exposure. Cellular homeostasis (alkaline phosphatase) mechanisms were also perturbed. The immunocytotoxic endpoints reflected differences in haemocyte proportions in the haemolymph of Cd-exposed mussels. Exposure to Cd also led to the formation of several nuclear aberrations in the gill cells of mussels. Overall the laboratory study highlighted toxic effects of Cd on green-lipped mussels that were dependent on the dose and/or the duration of exposure to Cd. Among the biomarkers tested, clearance rate, metallothionein-like protein induction and the formation of nuclear aberrations in mussel gill cells correlated strongly to Cd accumulation levels and reflected Cd exposure effects.
The feasibility of employing green-lipped mussels as bioindicators was tested during the field study. Green-lipped mussels were collected from different coastal sites along the South Island in NZ. Metal concentrations in the sediment and in four different mussel tissues were analysed. The findings indicated a significant geographical difference in metal concentration in the environment and in the metal accumulation levels in the mussels. Overall, the field study indicated that the green-lipped mussel, Perna canaliculus has the potential to be used as a bioindicator species for assessment of coastal metal pollution levels in NZ.
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Auswirkungen der Wasserqualität auf die elektrischen Signale von Apteronotus albifrons (Linnaeus, 1766)Moll, Rainer. January 2002 (has links)
Konstanz, Univ., Diplomarb., 2001.
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Noninvasive crayfish cardiac and behavioral activities monitoring systemPAUTSINA, Aliaksandr January 2015 (has links)
Crayfish provide a model which is simple, has an easily-accessible cardiovascular system and can be maintained in the laboratory conditions; the model has good utility for water quality assessment and ethophysiological studies. A noninvasive crayfish cardiac and behavioral activities monitoring (NICCBAM) system is discussed in the thesis. The system is inexpensive, has relatively few components and permits long-term continuous simultaneous monitoring of cardiac and behavioral activities of several crayfish. Moreover, compared to other available systems, it provides a novel approach of cardiac activity shape analysis which allows improving monitoring accuracy as well as obtaining additional information on crayfish functional state. The NICCBAM system was evaluated by comparing with the well-known electrocardiography system which demonstrated that cardiac contractions with both approaches were synchronous and that both signal shapes were similar. Experiments on crayfish cardiac activity relative to selected odors and chemicals demonstrated the promising potential of cardiac signal shape analysis, not only for detecting changes in the aquatic environment, but also for their classification.
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Možnosti využití střevlíkovitých (Coleoptera: Carabidae) k monitorování stupně narušení životního prostředíPurchart, Luboš January 2006 (has links)
No description available.
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Avaliação do potencial de acumulação de 210Pb pela Tillandsia recurvata L. para fins de biomonitoração da qualidade do ar.ALMEIDA, Amanda Correia de 31 August 2015 (has links)
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Previous issue date: 2015-08-31 / CNPQ / A biomonitoração do ar pode utilizar organismos que têm estreita relação ecofisiológica com a atmosfera e alto grau de acumulação de elementos estáveis e/ou instáveis. Dentro deste tema, as plantas epífitas têm sido amplamente utilizadas como biomonitores, sendo consideradas ferramentas eficientes na avaliação de deposição atmosférica. Contudo, não se tem estudos que evidenciem a eficiência de acumulação de 210Pb na espécie T. recurvata L. Com base nisto, o presente trabalho avaliou a aplicabilidade da Tilandsia recurvata L. para determinação do 210Pb, investigando o potencial de acumulação deste biomonitor em condições laboratoriais e quando exposto em uma região com níveis de radioatividade natural significativos, como é o caso da região de Paulista e Igarassu. Estes municípios estão inseridos na região urano-fosfática do Nordeste brasileiro. As espécies de T. recurvata L. foram coletadas, tratadas e acondicionadas em bolsas de náilon e separadas, posteriormente, para a realização dos dois experimentos. O experimento em laboratório consistiu na avaliação do potencial de acumulação de 210Pb pela T. recurvata L., onde os biomonitores foram acondicionados em recipientes com cúpula transparente e levados à casa de vegetação, e sob condições naturais foram submetidos a níveis controlados de exposição ao radionuclídeo em questão. O outro experimento baseou-se na instalação das espécies em pontos selecionados para monitoração em campo, nos municípios de Paulista e Igarassu. Após o término de exposição, as amostras foram secas em estufa, maceradas, dissolvidas e levadas às análises radioquímicas para determinação de 210Pb. A concentração de atividade de 210Pb para cada amostra foi medida em um detector proporcional de fluxo gasoso. Os resultados obtidos com este trabalho confirmam a importância da espécie Tillandsia recurvata L. como ferramenta para o estudo da biomonitoração do 210Pb, por apresentar respostas mensuráveis, configurando-se a eficácia dessa espécie como bioparâmetro de análise para o diagnóstico de 210Pb atmosférico, além de ser o primeiro resultado de biomonitoração ativa da dispersão de 210Pb, em condições laboratoriais e nas regiões de monitoração. / The air biomonitoring can be carried out using organisms having a close relation ecophysiologic with the atmosphere and a high degree of accumulation of stable and / or unstable elements. Within this theme, the epiphytic plants have been widely used as biomonitors, considering efficient tools in the evaluation of atmospheric deposition. However, do not have studies that show the 210Pb accumulation efficiency in the species T. recurvata L. Based on this, the present study evaluated the applicability of Tilandsia recurvata L. for determining the 210Pb, investigating the potential to accumulate in this biomonitor conditions laboratory and when exposed in a region with significant levels of natural radioactivity, as is the case of Sao Paulo and Igarassu region. These municipalities and are inserted into furan-phosphate region of Northeast Brazil.The T. recurvata L. species were collected, processed and packed in nylon bags and separated later to carry out the two experiments. The laboratory experiment was to evaluate 210Pb accumulation potential by T. recurvata L. where biomonitors were acondicion in containers with transparent dome and taken to a greenhouse and under natural conditions were subjected to controlled levels of exposure to radionuclide in question. The other experiment was based on the installation of samples at selected points for field monitoring in the municipalities of São Paulo and Igarassu. After the end of exposure, the samples were oven dried, macerated, dissolved and brought to radiochemical analysis for determination of 210Pb. The concentration of 210Pb activity for each sample was measured in a gas flow proportional detector. The results of this study confirm the importance of the species Tillandsia recurvata L. as a tool for the study of biomonitoring of 210Pb, by presenting measurable responses, setting the efficacy of these species as bioparameter analysis for diagnosis of atmospheric 210Pb, and be the result of the first active biomonitoring of 210Pb dispersion in laboratory conditions and in the monitoring regions.
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Biomonitoring of heavy metals in the Eerste River catchment areaElmayhob, Esam S. A. January 2020 (has links)
Philosophiae Doctor - PhD / The risk of increasing global pollution dictates the need to understand environmental processes and develop innovative ways to monitor pollution levels and address associated problems. In order to address this need, this study used a selection of plants leaves (Commelina benghalesis, Paspalum urvillei, Persicaria lapathifolia and Salix babylonica) as biomonitors to assess the state of the environment, more specifically the concentration of certain heavy metal pollutants (Cu, Zn, Fe, Ni, Pb and Cd) of river water and soils in the Eerste River catchment, Western Cape, South Africa.
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IN VIVO QUANTIFICATION OF HEAVY METALS IN BONE AND TOENAIL USING X-RAY FLUORESCENCE (XRF)Xinxin Zhang (8974130) 23 June 2020 (has links)
<p><b><i>Background and
Objective:</i></b> Pb
is a well-known toxic metal that can accumulate in bones over time and still
threatening large populations nowadays, even those who are environmentally
exposed to it. Strontium (Sr) is a metal directly related to bone health and
has been used in the treatment of osteoporosis disease as a supplement. Manganese
(Mn) is an essential nutrient in the body, yet excessive Mn is toxic and
affecting many organ systems. Another toxic metal, mercury (Hg), has been
poising different populations primarily through seafood consumptions,
especially inducing neurological disorders in infants and fetuses. Even though significant associations between
the above metal exposures and health outcomes have been recognized over the decades,
the current technologies are limited in assessing cumulative long-term
exposures <i>in vivo</i> to evaluate such
associations further. Bone and toenail are appropriate biomarkers to reflect
long-term exposure due to the longer half-life of these metals in them than in the traditional biomarkers. Therefore, this work evaluated the usefulness of portable x-ray
fluorescence (XRF) technology on <i>in
vivo</i> quantification of Pb and Sr in bone, and Mn and Hg in toenail.</p>
<p><b><i>Materials and
Methods:</i></b> The
portable XRF device was calibrated by using the Pb- and Sr-doped
bone-equivalent phantoms, and Mn- and Hg-doped nail-equivalent phantoms, correspondingly
in different projects. Seventy-six adults (38-95 years of age, 63 ± 11 years)
from Indiana, USA, were recruited to participate in this study. For the <i>in vivo</i> bone measurements, each
participant was measured at the mid-tibia bone using the portable XRF and K-shell
XRF system (KXRF). We estimated the correlation between the bone Pb concentration
measured by both devices to evaluate the use of the portable XRF in the bones. Using
the portable XRF, the bone Sr exposure of the study population were
simultaneously assessed with the bone Pb exposures. Besides, we analyzed the
mid-tibia bone Sr data of a Chinese population, which were measured with the
same portable XRF device by our research group. We also examined the extent to
which the detection limit (DL) of the portable XRF was influenced by scan time
and overlying soft tissue thickness for both Pb and Sr. </p>
<p>For the
exposure assessment of Mn and Hg in toenails, we first established system
calibrations and determined the DL with phantoms. In order to validate the portable XRF in a population
study, the recruited participants were measured at the big toenail by the device,
and their toenail clippings were analyzed by the inductively coupled plasma
spectrometry (ICP-MS). Besides, we analyzed the toenail data of an
occupationally-exposed population, collected by our collaborators in Boston. A
portable XRF device with the same model as ours was used in that study. </p>
<p><b><i>Results:</i></b> The uncertainty of <i>in vivo</i>
individual bone measurement increased with higher soft tissue thickness
overlying bone, and reduced with extending measurement time. With thickness ranging
from 2 to 6 mm, the uncertainty of a 3-minute <i>in vivo</i> measurement ranged from 1.8 to 6.3 ug/g (ppm) for bone Pb and from
1.3 to 2.3 ppm for bone Sr. Bone Pb measurements via portable XRF and KXRF were
highly correlated: R=0.48 for all participants, and R=0.73 among participants
with soft tissue thickness < 6 mm (72% of the sample). A trend of different bone
Sr concentrations was observed across the races and sexes. </p>
<p>The DL
of the portable XRF with 3-minute toenail measurements was 3.59 ppm for Mn and
0.58 ppm for Hg. The portable XRF and ICP-MS measurements were highly
correlated in the occupational populations for both Mn (R = 0.59) and Hg (R =
0.75). A positive correlation
(R = 0.34) was found for toenail Mn measurements in the environmentally-exposed
population, while a non-significant correlation was observed for toenail Hg due to the extremely low-level
of Hg (Mean = 0.1 ppm) in the study population. </p>
<p><b><i>Discussion and
Conclusion:</i></b>
The portable XRF could be a valuable tool for non-invasive <i>in vivo</i> quantification of bone Pb and Sr, especially for people
with thinner soft tissue; and of toenail Mn and Hg, especially for people with
moderate- to high-level exposures. </p>
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The Effects of Exposure to Trace Elements on the Skeletal Health of American MinkFraschetti, Ariana January 2021 (has links)
The release of pollutants by the oil sands industry and pulp and paper mills has been an ongoing environmental concern for decades. Such toxins have been linked to declining reproductive and skeletal health in wildlife species, as they have known endocrine disrupting properties that interfere with hormones responsible for proper reproduction and bone development. As such, declining population sizes because of pollutant exposure has been correlated with altered bone health in mammals. For the purposes of environmental monitoring, the development of a biomarker of pollutant exposure would be a beneficial tool to assess pollution impact on wildlife populations. Therefore, the purpose of this research was to identify this biomarker in the American mink based on measures of their bone health. Mink from the Athabasca Oil Sands Region and an area surrounding a pulp and paper mill in
Quebec were collected. From each mink, a hindlimb femur and the baculum (for males) were
dissected. Bones were evaluated through a series of tests to quantify key cortical and cancellous bone structural and material properties. These included dimensional analysis, three-point bending and micro-Computed Tomography. Toxicology reports of trace element exposure levels in the minks were also provided by ECCC. Principal component analyses and correlation matrices were used to identify potential relationships between the bone metrics and trace element levels, followed by linear regression modeling. Results found that the baculum and femur structural properties were correlated with selenium, rubidium and iron concentrations, suggesting that these elements had the strongest influences on bone health for the mink studied here. This work provides the basis for future research on identifying a biomarker determinant of bone health to be used in environmental monitoring effects programs. The results here indicate that baculum bone measures are dominated by trace element effects rather than loading effects and are thus a useful bone to investigate for biomonitoring programs. This will provide a simple and reliable method for determining whether there are unsustainable levels of pollution in regions across North America. / Thesis / Master of Applied Science (MASc) / Environmental pollution in regions across Canada puts the health of communities and wildlife at risk. To better measure the impact of pollution in these regions, the implementation of a species monitoring program would benefit those communities who are at the greatest risk. Therefore, this research was aimed at developing an indicator of harmful pollution exposure in mink, an abundant species in Canada, by investigating their bone health. A group of mink from Alberta and Quebec were collected and their femur and penile bones tested for a variety of bone health measurements. In addition, information on the heavy metal levels in the mink livers were provided. The bone health measurements and heavy metal levels were then compared to look for any relationships between them. This research found that selenium, rubidium and iron had the strongest effects on bone health. The methods used have set the groundwork for using minks to monitor pollution levels across
North America.
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Studies of Benthic Macroinvertebrate Use for Biomonitoring of Mid-Atlantic Highland StreamsMoeykens, Michael David 28 May 2002 (has links)
Research was conducted in three areas of water quality assessment. Long term ecological monitoring data from Shenandoah National Park (SNP) were analyzed and a protocol for data analysis was presented. Streams in SNP were found to be comparable to the best that can be found in the Blue Ridge ecoregion. Land use in SNP (mostly for recreational purposes) does not appear to be causing impairment to the macroinvertebrate assemblages. Streams in the SNP were found to recover quickly from disturbance.
The Macroinvertebrate Aggregated Index for Streams (MAIS) was found to have an overall classification efficiency (CE) of 86% in the Ridge and Valley ecoregion, and an overall CE of 91% in the Central Appalachians ecoregion. Refinement of the MAIS for use in the Blue Ridge ecoregion resulted in an increase of the overall CE to 78%. The CE for reference sites in the Blue Ridge was 75%, and the CE for degraded sites was 87%.
An intensive study of a stream (Peak Creek) with suspected heavy metal impairment showed that capping of an industrial waste site has resulted in improvements to the macroinvertebrate assemblages. The source of the impairment was not linked solely to heavy metals, but was found to be a mixture of pollution sources and environmental stress. / Ph. D.
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Toward improved assessment of freshwater salinization as a benthic macroinvertebrate stressorTimpano, Anthony J. 27 September 2017 (has links)
Salinization of freshwaters by human activities is of growing concern globally. Salt pollution can cause adverse effects to aquatic biodiversity, ecosystem function, ecosystem services, and human health. In many regions of the world, and in coal-mining-influenced streams of the temperate forests of Appalachia USA, specific conductance (SC), a surrogate measure for the dissolved major ions composing salinity, has been linked to decreased diversity of benthic macroinvertebrates. However, assessments used to reach this conclusion have generally not accounted for temporal variability of salinity, as most studies use "snapshot" SC data collected concurrently with biological data at a single point in time. Effective management of salinization requires tools to accurately monitor and predict salinity while accounting for temporal variability. To improve those tools, I conducted analyses of 4.5 years of salinity and benthic macroinvertebrate data from 25 forested headwater streams spanning a gradient of salinity where non-salinity stressors were minimized. My objectives were to: 1) model the annual pattern of salinity, 2) determine if salinity measures derived from continuous data are more precise than snapshot SC as predictors of aquatic biology, and 3) quantify response to salinity of the benthic macroinvertebrate community. A sinusoidal model of the annual cycle of SC using daily measurements for 4.5 years revealed that salinity naturally deviated ± 20% from annual mean levels, with minimum SC occurring in late winter and maximum SC occurring in late summer. The pattern was responsive to seasonal dilution as driven by catchment evapotranspiration dynamics. Alternative discrete sampling intervals can approximate the pattern revealed by continuous SC data if sampling intervals are ≤ 30 days. Continuous SC variables did not significantly improve precision for prediction of benthic macroinvertebrate metrics (p > 0.1) as compared to snapshot SC using generalized additive mixed models.
Results suggest that snapshot SC is a capable predictor of benthic macroinvertebrate community structure if sampling is carefully timed. However, continuous SC data can quantify chronic salt exposure, which supports a hypothesis to explain how temporal variability of field-based observations of salt sensitivity of benthic macroinvertebrate taxa may be influenced by life stage. Benthic macroinvertebrate community structure diverged from reference condition as salinity increased, with stronger relationships in Spring than in Fall. Intra-seasonal variation in community structure was also revealed across sampling dates. Non-Baetidae Ephemeroptera were most sensitive to salinity, with richness and abundance lower than reference at SC > 200 =µS/cm in Spring based on snapshot SC. Equivalent effects were predicted by mean monthly SC of 250-300 µS/cm from the prior Fall. Continuous conductivity monitoring may improve assessment of salinity effects because they can describe life-cycle exposure, which may aid investigations of mechanisms driving field-based observations of benthic-macroinvertebrate community alteration. / Ph. D.
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