Search

A dual-celled biobed was built at the Ian Morrison N. Research farm in Carman, MB to degrade and retain the pesticides from pesticide rinsate derived at the farm. The biobed was designed for Manitoba conditions with considerations taken from existing biobeds in the Province of Saskatchewan. Temperature and moisture of the biomixture contained within the biobed was monitored using probes for the duration of the study. Three pesticides (2,4-DB, dicamba, and metrafenone) were detected in the biomixture prior to pesticide input from rinsing in 2020 but had degraded by the end of the season and were no longer detected. The Influent of the biobed was analyzed for a suite of pesticides and 23 pesticides and one pesticide metabolite were detected. In Effluent One only 11 of the 24 compounds were detected, and six compounds were detected in Effluent Two. Total pesticide concentrations significantly decreased for Influent > Effluent One > Effluent Two. Pesticides detected in the effluents tended to have higher GUS or Koc values. In 2021, a large influx of prepared spraying liquid containing glufosinate (approximately 680L) overburdened the biobed and resulted in reduced degradation and increasing mean concentrations from Influent > Effluent One > Effluent Two. Glufosinate and seven other pesticides detected in the influent were not measured in biomix due to method limitations. There were three pesticides (bifenthrin, trifloxystrobin, and diuron) detected in the biomixture samples in 2021, and only diuron, which had the highest GUS and Koc values, was still detected at the end of the season.

By screening for up to 172 pesticide compounds (primarily herbicides and insecticides), this research investigated the types and concentrations of pesticide compounds present in water-column and bottom-sediment samples collected from four rivers in the Province of Manitoba, Canada. A total of 34 unique compounds were detected in the water-column (n=202) with broadleaf herbicides among the most frequently detected (2,4-D, bentazone, clopyralid, MCPA), in addition to herbicides atrazine and metolachlor that are widely used in the United States Corn Belt. Herbicide triclopyr was only detected after the Red River entered urban landscapes in Manitoba but many other unique active ingredients were already detected in the first sampling station immediately after the Canadian-United States border. Only 6 unique compounds have set Canadian Water Quality Guidelines for the Protection of Aquatic Life, and their guidelines were never exceeded. A total of 32 unique compounds were detected in bottom sediments (n=94) of which 78% are current-use active ingredients in Manitoba. In addition to sediments, pesticides can be sorbed to other constituents present in rivers such as microplastics which are believed to be carriers of legacy insecticide DDT (dichlorodiphenyltrichloroethane). This study investigated the sorption of current-use herbicides (2,4 D, atrazine, glyphosate) by microplastics which was virtually negligible, except for glyphosate sorption by PVC (35%). In contrast, the sorption of DDT by these same microplastics was always >50% (of the initial DDT in solution). Finally, this study investigated the efficiency of single and dual-cell biobeds in the Prairies to minimize point-source pollution by allowing the capture and degradation of pesticide residues associated with sprayer rinsing. With a few exceptions (clopyralid, fluroxypyr and imazethapyr), biobeds always showed to be highly effective in reducing pesticides concentrations in rinsate. The PTI (Pesticide Toxicity Ind

The extensive use of sulfamethoxazole (SMX) as a veterinary antimicrobial in the Canadian swine industry increases its occurrence in manure. Land application of swine manure enhances the dispersal of SMX in the environment, increasing the risk of antibiotic resistance development in bacteria, one of the focal human health emergencies of our times. Humic acid (HA) and fulvic acid (HA) from the dissolved organic carbon (DOC) fraction in fresh liquid swine manure influence the sorption of SMX onto smectite clays, hence the environmental fate. This research aimed to elucidate the effect of fresh liquid swine manure DOC species in fresh liquid swine manure on SMX sorption onto bentonite. Specific objectives were to (i) elucidate the physicochemical characteristics of HA and FA isolated from fresh liquid swine manure DOC and (ii) assess their contribution to the mechanisms controlling SMX sorption onto bentonite clay. Humic substances were extracted and characterized for their physicochemical properties. A batch sorption study with a randomized complete block design was used to quantify the SMX sorption, explicit clay-mineral surface and interlayer sorption, and probe fluorescence quenching in humic substances by SMX. Results showed that FA was the dominant component of DOC in the fresh liquid swine manure examined in this study (10 FA: 1 HA). Thus, FA determined the major portion of organic matter coating on the mineral bentonite and binding of SMX. Spectroscopic analysis revealed that hydrophobicity (53.0% HA, 56.5% FA), hydrophilicity (34.0% HA, 35.1% FA), aromaticity (34.0% HA, 37.2% FA), and aliphaticity (66.0% HA, 62.7% FA) of the two humic substances were similar despite the differences in their functional groups. Solid state 13C-NMR data and X-ray Photoelectron Spectroscopic data revealed that the core and the surface of HA and FA secondary structures were substantially different. The orientation of functional groups in clay mineral-bound HA and FA and free aqueou

Indigenous populations living on reserves in Canada today are still experiencing uneven access to drinking water services. Past studies of First Nation communities have observed microbiological contamination where no drinking water advisory was issued for fecal indicator bacteria (FIB) and detection of emerging contaminants: antibiotic resistance genes (ARG). The first study sought to observe fluctuations in the distribution system of traditional coliform indicators against antibiotic resistance genes as well as Campylobacter spp. quantification. Results found repeated detection of indicator bacteria from drinking water samples in homes with concrete cisterns in community B, as well as in community D up to 600 CFU/ 100 mL coliforms. Both Campylobacter coli and Campylobacter jejuni, diarrheal infection culprits, were also observed in instances without the previous or same-time detection of coliform, including at sampling sites like treated water from taps at the water treatment plant and piped homes. ARGs were more apparent in post-treated water from community B than from community D and in water treatment plant and piped samples. The second study sought to characterize ARGs through shotgun metagenomics to establish the resistome from water. Results determined pre-treated source water samples were characteristically distinct from post-treated cistern water from each community suggesting the presence of an alternative source of contamination for stored drinking water. Indigenous nations continue to experience water insecurity and these study results reinforce community concerns over water quality thus we aim to support change led within communities for strengthening the management of water distribution to homes.

The goal of this thesis is to develop an improved understanding of sedimentary processes along the Nelson River system in the subarctic region of Canada. Sediment sources and transport dynamics in Lake Winnipeg, the Upper Nelson River (UNR) – between Lake Winnipeg and Split Lake – as well as the Burntwood River (BR) – the major tributary of the Nelson River in the subarctic region – were investigated. The properties of Lake Winnipeg’s bottom sediment and the lake’s total sediment budget were used to provide a better understanding of: a) the sedimentation dynamics in Lake Winnipeg; and b) its role in sediment transport in the Nelson River system. The sediment source fingerprinting technique and long-term record of sediment load data on the BR and the UNR were used for separating the importance of climate change from human-induced environmental changes on these two regulated rivers. Moreover, the influence of Split Lake on the downstream delivery of sediment to the Lower Nelson River and Hudson Bay was investigated by developing the sediment budget for this riverine lake. In addition, the collection of a representative sample of ambient suspended sediment using a well-established time-integrated sampler and two adapted discrete samplers was investigated. The performance of these samplers was examined in a controlled laboratory and under field conditions. Assessing these samplers was conducted to determine the most suitable device to collect representative bulk samples from the Nelson River system. The results show that the sediment load derived from the prairies area is sequestered in Lake Winnipeg, along with nutrients and contaminants bound to them. Another key finding was that sediment derived from bluff erosion on the northern shore of the lake is the major source for sediment being exported in the lake’s outflow. This thesis also found that the UNR is characterized by increases in sediment loading as a result of climate change. However, in the BR, cross-watershed

Approximately 50% of the homes on First Nation reserves in Manitoba, Canada, receive piped water from water treatment plants (WTP). Of the remaining homes, 31% are equipped with cisterns filled by a water truck. The overall objective of this thesis research was to compare the quality of tap water in homes with piped water versus those with cisterns. The study was in collaboration with three First Nations communities in Manitoba. Each community was predominantly equipped with belowground concrete cisterns, belowground fibreglass cisterns, or aboveground polyethylene cisterns stored in insulated shelters. Free residual chlorine concentration was significantly lower in water samples from homes with cisterns than piped water. The frequency and severity of Escherichia coli and total coliform contamination were significantly greater in drinking water from belowground concrete and fibreglass cisterns than in piped water samples in each community. The contamination of belowground cisterns by coliform bacteria was greatest in late spring. Data obtained under the Access to Information Act for 2014 and 2018 showed no clear evidence of improved water quality in any of the Tribal Councils linked to the three communities. Field and laboratory chlorine disappearance studies indicated a greater contribution of concrete cistern walls than bulk water to the disappearance, hence lowering free residual chlorine concentration in belowground cisterns. Treated water from the WTP in two of the First Nations communities frequently exceeded the Health Canada guideline of 100 µg L-1 total trihalomethanes (TTHMs), as did 75% of piped water samples and 70% of cistern water samples. Although the water distribution system had no significant effect on TTHM concentration, sampling month significantly affected due to temporal changes in source water dissolved organic carbon content. Dissolved organic carbon removal before further water treatment might be an important process in effectively reducing

Microplastics (plastic particles <5.0 mm in diameter) have been detected in freshwater ecosystems worldwide, yet little is known about the fate and behaviour in Canadian freshwater systems. Knowledge gaps include the influence of ice formation, water quality (i.e., nutrients enhancing both biofilm and filamentous algae growth), and the presence of aquatic plants (cattails) on fate and behaviour of microplastics. I conducted two field-based mesocosm studies at the Prairie Wetland Research Facility at the University of Manitoba. The first mesocosm study was a long-term 622-day study where five different microplastic types (foams, films, fragments, microbeads and fibres) were added to understand long-term microplastic fate and behaviour during distinct seasons and overwintering. The second study was a short-term 251-day study using model constructed freshwater mesocosms where both films and fibres were added to understand whether nutrients, cattails and overwintering affected microplastic fate and behaviour. In both studies, distinct open water seasons (spring, summer, fall), over wintering and subsequent spring melt of ice lead to unique behaviours of different types of microplastics i.e., resuspending, and settling. In the second study, I found that biofilm and filamentous algal growth were enhanced by the nutrient addition were the likely drivers of microplastic settling and resuspension behaviour in the mesocosms through biofouling, defouling (biofilms) and trapping microplastics as enhanced filamentous algal growth occurs. Overall, substrate may not be the ultimate sink for microplastics as previously thought, as microplastic behaviour (e.g., aggregation, biofouling), and characteristics of the aquatic ecosystem (e.g., climate, ice crystal formation, and water temperature-density effects) will add to the complexities of microplastic behaviours and will determine their ultimate fate in freshwater ecosystems. This thesis has begun to advance our understanding of mic

As global warming progresses, the Arctic sea-ice extent has decreased rapidly over the past decades, leading to an increase in oil and gas exploration and marine transportation in the Arctic. It is thus important to develop and evaluate oil spill remediation strategies to deal with the increasing risk of crude oil spilled in the Arctic marine environment. Integral to this is understanding the potential for photochemical and microbial transformation processes to degrade the oil in an Arctic marine environment and in the presence of sea ice. This thesis reports a mesocosm-scale oil-in-sea-ice experiment involving a light crude oil conducted at the University of Manitoba’s Sea-ice Environmental Research Facility (SERF) in January–April 2018. The degradation of the oil and production of polar, oxygen-containing compounds were studied by direct infusion electrospray ionization ion mobility time-of-flight high-resolution mass spectrometry (ESI-IM-TOF-HRMS). The data suggests that degradation takes place even when spilled oil is encapsulated in sea ice, as supported by an increase in the occurrence of polar oxygen-containing compounds over time, and a growth of microbial degraders of hydrocarbons as the oil-brine contact increases. Interestingly, ion mobility drift time data shows a decline in cross sectional area of oxidized by-products, despite the fact that the addition of oxygen typically increases molecule size of intermediate by-products. Challenges encountered in non-targeted analysis of oil-in-ice samples are also documented and discussed. This study furthers our understanding of the weathering processes that affect crude oil in a sea ice-covered marine environment and gives detailed information regarding efficient analysis of the relevant oxidized by-products.

This study determined the microbiological quality of drinking water from various water distribution systems of two First Nation communities in Manitoba, Canada. E. coli, other coliforms as well as different types of antibiotic resistance genes (ARGs) were more often detected in water from homes with cisterns than homes with the direct-lined piped system. Cistern water showed the presence of bacteria, as well as ARGs, and had free chlorine concentrations less than the World Health Organization (WHO) standard recommended level that is 0.2 mg/L. Also, environmental changes affect the fecal bacterial counts as warmer months showed higher counts than the colder months. Moreover, this study also showed the presence of mecA gene carrying Mammaliicoccus fleurettii in lake water which is used as source water and recreational purposes in a First Nation community in Manitoba, Canada. Our study suggests that both drinking water and recreational water should be monitored for taking further steps to protect the community residents’ health from waterborne illness.

Biosolids contain contaminants, including antibiotics, which are ingested by humans and excreted intact or as metabolites. Land application of biosolids could be a pathway for antibiotic release into the environment. The presence of antibiotics in the environment could lead to the promotion of bacterial resistance in microorganisms, with dire consequences for human health due to the severity of antibiotic resistant infections. Phytoremediation may reduce antibiotic concentrations in biosolids and wastewaters prior to land application. Three main studies were conducted to (i) characterize the dissipation of sulfamethoxazole and trimethoprim in biosolids; (ii) evaluate the extent and kinetics of sulfamethoxazole sorption by cattail and switchgrass roots; and (iii) evaluate the uptake and translocation of ciprofloxacin and sulfamethoxazole by cattail and switchgrass. Sulfamethoxazole dissipated rapidly under both saturated (99% dissipation) and unsaturated (96% dissipation) conditions, indicating a lower persistence of sulfamethoxazole in biosolids, while trimethoprim was more persistent under unsaturated (25% dissipation) compared to saturated conditions (95% dissipation). Switchgrass roots were more effective than cattail roots in removing sulfamethoxazole from aqueous solutions through sorption. Percentage sulfamethoxazole removal at the three temperatures tested (5, 15, and 25 °C) was 26 – 33% for cattail and 60 – 77% for switchgrass. Phytoextraction of antibiotics was lower for switchgrass (9.8% for both ciprofloxacin and sulfamethoxazole) than for cattail (~34% for ciprofloxacin and ~20% for sulfamethoxazole). Both plant species concentrated antibiotics in the roots, with poor translocation to the aboveground biomass. Harvesting of both aboveground biomass and roots of cattail would be more effective in the phytoextraction of ciprofloxacin compared to switchgrass. Overall, our results indicate that reducing conditions favoured trimethoprim dissipation, which was

The Ininiw of Manitou (God's) Sakahigan (Lake), now known as God's Lake First Nation (GLFN), are an Indigenous people of Turtle Island, now called North America. As a GLFN Ininiw, I tell my autoethnography, drawing on a half-century of experience, both personal and professional, as well as a literature review, government data, and fieldwork. The medicine wheel framework required that I consider the spiritual, physical, emotional, and mental aspects of GLFN's water governance. I applied another Medicine wheel teaching regarding the Indigenous learning process to analyze this data, which provided an analytical framework to systematically process the data through heart, mind, body, and spirit. This thesis provides abundant evidence that the Ininiw of GLFN did not "cede or surrender" water governance in their traditional territory. Living in a lake environment, the GLFN Ininiw have survived, lived, thrived, and governed the aski (land and water) granted by Manitou (Creator) for thousands of years according to natural law. Through Ininiw governance, we kept God's Lake pristine. As GLFN Ininiw people's Aboriginal and treaty rights to govern over the waters of our ancestral lands were never surrendered, the GLFN Ininiw hold this governance still. I argue that natural law requires Canada and Manitoba to cede governance over aski to the GLFN Ininiw for their traditional territory. To sustain all Creation, the Ininiw assert our sovereignty over water in our traditional territory as was granted by Manitou (Creator). This sacred pact with Manitou requires a shift in water governance to fall under First Nation self-government. This perspective requires water to be considered sacred and a health issue, rather than a technical or infrastructure issue. This reconstitution of water under the health jurisdiction will ensure safe drinking water and restore women's central role in its governance.

Half of households on First Nations reserves in the Province of Manitoba do not have access to piped water, but rather rely on cisterns or wells, or have no running water (e.g., buckets). The purpose of this research was to assess whether First Nations perceptions of water is dependent on the type of water distribution system associated with the household. From July 2017 to October 2018, household surveys were developed in collaboration with each of three First Nations in Manitoba (Community A, B and C) and participants were recruited by going door-to-door in each community. Using a total of 273 responses, the study applied a factor analysis and found that four factors explained the majority of the underlying variance among survey answers: Safety, Sufficiency, Acceptability and Human Health. Households with cisterns reported significantly more safety and sufficiency concerns compared to households with piped water. Deductive and inductive analysis of open-ended survey reponses identified how households were describing their concerns. Households with safety concerns described finding contaminants in their water (e.g., dirt) and some households expressed concerns surrounding insufficient community resources to fix the water safety problems (e.g., additional water cleaning equipment and staff are needed). Households lacking sufficient water described not being able to keep up with their basic family needs (e.g., cleaning, laundry and bathing). Descriptions of negative health concerns caused by the household’s water largely included descriptions of gastrointestional illness symptoms or skin irritations. Importantly, the research also examined whether survey participants had full access to water, as defined by the United Nation’s General Assembly Resolution 64/292, The Human Right to Drinking Water and Sanitation, A/RES/64/292 (28 July 2010). The analysis indicated that 60.8% of households were not able to access water as described in this Human Right Resolution especial

Pesticides are used to control pests in a variety of habitats including agricultural lands, forests, commercial lands, and domestic properties. Pesticide transport from such habitats to surface waters leads to environmental contamination. The objectives of this research were to compare the pesticide types present in the water-column and bottom-sediments of rivers flowing through intensively-managed and semi-natural habitats and to examine the extent of variations in MCPA and 2,4-D concentrations in the sediments that could be explained by measured laboratory parameters such as Kd, sediment organic carbon content and particle size distribution. This study screened water-column and sediment samples for 160 pesticide compounds which is substantially greater than what has been typically included in Prairie surface water research. River contamination primarily arises as a result of current-use pesticides applied in agricultural and urban habitats. For most compounds detected, there was no significant correlation between their concentrations detected in water and sediments, suggesting that pesticide concentration in the water-column is a poor indicator of the presence of pesticides in sediments. Pesticide mixtures were more common in water (72%) than sediments (51%) and dominated by broadleaf herbicides. The concentrations of pesticide mixtures detected in water never exceeded their calculated threshold value for the Pesticide Toxicity Index, indicating that the presence of pesticides in Prairie rivers continue to pose no significant risks to freshwater organisms. The batch-equilibrium study found that regardless of the lower sorption to sediments, more frequent presence of MCPA in the water-column allowed for greater opportunities for MCPA to partition to sediments compared to 2,4-D. Thus, the water-column loadings of those compounds, and not sediment characteristics, are the driving force for determining their frequencies and concentrations in sediments. Since this stud