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8. Non-invasive biomonitoring of polar bear feces can be used to estimate concentrations of metals of concern in traditional food.

Author

Eccles, Kristin M., Boutet, Vincent, Branigan, Marsha, Dyck, Markus, van Coeverden de Groot, Peter, Lougheed, Stephen C., Rutter, Allison, and Langlois, Valérie S.

Subjects
POLAR bear, BIOLOGICAL monitoring, METALS, COMMUNITY-based programs, ENVIRONMENTAL exposure
Abstract

The Arctic faces increasing exposure to environmental chemicals such as metals, posing health risks to humans and wildlife. Biomonitoring of polar bears (Ursus maritimus) can be used to quantify chemicals in the environment and in traditional foods consumed by the Inuit. However, typically, these samples are collected through invasive or terminal methods. The biomonitoring of feces could be a useful alternative to the current metal monitoring method within the Arctic. Here, we aim to 1) quantify the relationship between concentrations of metals in the feces and tissues (muscle, liver, and fat) of polar bears using predictive modeling, 2) develop an easy-to-use conversion tool for use in community-based monitoring programs to non-invasively estimate contaminant concentrations in polar bears tissues and 3) demonstrate the application of these models by examining potential exposure risk for humans from consumption of polar bear muscle. Fecal, muscle, liver, and fat samples were harvested from 49 polar bears through a community-based monitoring program. The samples were analyzed for 32 metals. Exploratory analysis indicated that mean metal concentrations generally did not vary by age or sex, and many of the metals measured in feces were positively correlated with the internal tissue concentration. We developed predictive linear regression models between internal (muscle, liver, fat) and external (feces) metal concentrations and further explored the mercury and methylmercury relationships for utility risk screening. Using the cross-validated regression coefficients, we developed a conversion tool that contributes to the One Health approach by understanding the interrelated health of humans, wildlife, and the environment in the Arctic. The findings support using feces as a biomonitoring tool for assessing contaminants in polar bears. Further research is needed to validate the developed models for other regions in the Arctic and assess the impact of environmental weathering on fecal metal concentrations. [ABSTRACT FROM AUTHOR]

Published
2024
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22. Contamination, regulation, and remediation: an introduction to bioremediation of petroleum hydrocarbons in cold regions

Author

Snape, Ian, primary, Acomb, Larry, additional, Barnes, David L., additional, Bainbridge, Steve, additional, Eno, Robert, additional, Filler, Dennis M., additional, Plato, Natalie, additional, Poland, John S., additional, Raymond, Tania C., additional, Rayner, John L., additional, Riddle, Martin J., additional, Rike, Anne G., additional, Rutter, Allison, additional, Schafer, Alexis N., additional, Siciliano, Steven D., additional, and Walworth, James L., additional

Published
2008
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23. Landfarming

Author

Walworth, James L., primary, Reynolds, C. Mike, additional, Rutter, Allison, additional, and Snape, Ian, additional

Published
2008
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37. Characterization of Excreted Salt from the Recretohalophytes Distichlis spicataand Spartina pectinata

Author

Morris, Logan, Yun, Kassandra, Rutter, Allison, and Zeeb, Barbara A.

Abstract

Recretohalophytes are salt‐tolerant plants that excrete excess salts through specialized glands on their leaf surfaces. They have the potential to be applied as a phytotechnology to remediate salt‐impacted soils by removing the salt from the soil and allowing it to be mobilized on the wind (haloconducted) and hence dispersed over a wide area where the salt ions will act as nutrients rather than pollutants. This study is the first to characterize the excreted salts of two recretohalophytic grasses, Spartina pectinataBosc ex Link and Distichlis spicata(L.) Greene using scanning electron microscopy (SEM). At above‐optimal conditions for salt excretion (i.e., >65% humidity and >26°C), salt appeared on the stem and leaf surfaces as a sap‐like excretion that could not be easily mobilized. The mean diameter of the salt crystals excreted by S. pectinata(31 ± 24 μm) is significantly smaller than the diameter of those excreted by D. spicata(49 ± 22 μm) (p< 0.05). Spartina pectinataexcreted significantly more salt crystals per unit area of plant surface (60 ± 41 crystals mm−2) than D. spicata(27 ± 16 crystals mm−2). These salt crystal characteristics can now be used to assist with determining the optimal species for haloconduction, and in particulate dispersal modeling systems to help determine the fate of the excreted salts once they become airborne by wind. Recretohalophytes excrete salts that disperse via winds through “haloconduction.”The mean diameter of excreted salt crystals varied by plant species.The mean number of salt crystals per unit of leaf area varied by plant species.Air particulate modeling can use this to assess the effectiveness of salt dispersal.Salt excretion and dispersal may prove to be a useful form of salt remediation.

Published
2019
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45. An NMR study of human brain tumours: Phosphorus chemical shift imaging in vivo and high resolution proton spectroscopy of biopsy samples

Author

Rutter, Allison.

Subjects
Health Sciences, Pathology, nervous system diseases
Abstract

Human brain tumours have been investigated using proton and phosphorus nuclear magnetic resonance (NMR). The localization technique, chemical shift imaging has been used to obtain phosphorus spectra of tumours in vivo. High resolution proton spectroscopy has been performed on biopsy samples and extracts of human brain tumours. To obtain the localized phosphorus spectra, one dimensional chemical shift imaging with a surface coil was adapted to a 1.5 T Siemens Magnetom imager. The ratios of areas, PDE/ATP and PME/ATP were found to be higher in glioblastomas and astrocytomas than in normal brain. Pi/ATP and PCr/ATP were also high in astrocytomas. The pH of brain tumours ranged from alkaline to neutral, with meningiomas consistently having alkaline pH. A three dimensional localization sequence was written and tested on the Magnetom and used to obtain phosphorus spectra from the brains of normal volunteers. One dimensional $\sp1$H spectra, COSY spectra and T$\sb2$ data were obtained from ex vivo biopsy samples. A parameter, P, was defined as the ratio of the area between 3.4 and 3.1. ppm over the area between 1.5 ppm and 1.1 ppm. The parameter distinguished glioblastomas from astrocytomas and normal brain. This area parameter, P, also appeared to be indicative of malignant potential or biological aggressiveness. Crosspeaks in the ex vivo proton COSY spectra of brain specimens could be used to classify glioblastomas, astrocytomas, metastases to the brain, meningiomas and normal brain in agreement with histopathological diagnosis. The T$\sb2$ values at 1.3 ppm were fitted to a two exponential equation. The longer component could be used to separate clearly glioblastomas from normal brain, normal brain having a much longer long T$\sb2$ component. Astrocytomas formed a continuum of values between glioblastomas and normal brain, with the grade of the astrocytoma roughly correlating with the value of the long T$\sb2$ component. High resolution $\sp1$H spectroscopy of perchloric acid extracts of biopsy samples was performed. The extracts confirmed that lactate, acetate, creatine and choline derivatives, NAA, glutamate, glutamine, alanine, valine and leucine were present in the samples. Comparisons of extract and ex vivo spectra indicated that the 1.3 ppm peak in the ex vivo spectra is predominantly due to the methylene moiety of lipids.

Published
2009
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46. Vascular Plants in the Remediation of Saline Environments: A Dispersal Model using Recretohalophytes.

Author

Zeeb, Barbara, Litalien, Amelie, Raymond, William, and Rutter, Allison

Subjects
VASCULAR plants, WATER salinization
Abstract

Soil and water salinization are growing global concerns, adversely affecting both natural habitats and agricultural lands. A novel method for the remediation of salinized soils utilises recretohalophytes; - plants that secrete salts through specialized glands onto their leaf surfaces. In a process referred to as 'haloconduction', wind blows the excreted salts from the leaves of plants, dispersing and diluting them over great distances. In this study, a model was established to: i) estimate the amount of salt transferred from a given field site, and ii) determine the location and concentrations of deposited salts. Greenhouse and wind tunnel experiments using Sporobolus michauxianus were employed to determine excretion and salt emission rates. Based on this data, a theoretical emission profile for S. michauxianus was generated at an industrial field site contaminated with highly saline cement kiln dust. Modelling software (AERMOD View) was used to visualize the dispersal of the emitted salts. Simultaneously, a field monitoring program using passive (wet candles) and direct (HiVol) air samplers was undertaken to determine actual airborne chloride concentrations and chloride deposition rates. Based on this model, ~180 kg/year of potassium chloride (KCl) salt could be displaced from the site and deposited over a ~70 km² region, while maintaining deposition concentrations well below background levels. Similar models are underway for other sites including a salinized roadside and a petroleum extraction site where saline water was produced as a by-product. [ABSTRACT FROM AUTHOR]

Published
2023

47. Turning A New Leaf on Salinization: Phytoremediation of Contaminated Soils Using Halophytes.

Author

Nawroth, Lauren, Cartwright, Lyndsay, Rutter, Allison, and Zeeb, Barbara

Subjects
WATER salinization, SOIL salinization, HALOPHYTES, PHYTOREMEDIATION, ECOSYSTEMS
Abstract

Salinization of soils, surface- and groundwater are increasingly being identified as environmental concerns. In Canada, there are many sources of chloride contamination. As one of the largest users of road salt worldwide, Canada distributes over 5 million tonnes of this material each year. The copious amounts of salt applied to roads in winter have lasting effects in ecosystems located roadside and beyond, including the summer months. Other notable sources of chloride contamination in Canada include oil and gas production, and the production of saline material from various industries. Traditional methods of chloride remediation are often costly and labour intensive with negative impacts on the environment due to the generation of by-products, accelerated soil erosion, and edaphic soil conditions. Phytoremediation utilizing halophytes (i.e. salt tolerant plants), is being investigated as a way of remediating salt-impacted areas. Previous greenhouse and small-scale in situ studies have shown significant reductions in soil salinity using halophytes. In this study, native Canadian halophytes are being evaluated for their abilities to remediate salt contaminated soils at two different field sites. One site is located in a large metropolitan area where roads are treated with salts throughout the winter months for safety reasons. The second site is an industrial location previously used for petroleum extraction. The contrasts of the two field sites will allow for a comprehensive analysis of halophytic abilities in large-scale remediation applications. [ABSTRACT FROM AUTHOR]

Published
2023

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