Matching Items (137)
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This dissertation focused on studying risks associated with emerging drinking water contaminants and tradeoffs related to water management interventions. The built environment impacts health, as humans on average spend ~90% of their time indoors. Federal regulations generally focus on drinking water at the water treatment plant and within the distribution

This dissertation focused on studying risks associated with emerging drinking water contaminants and tradeoffs related to water management interventions. The built environment impacts health, as humans on average spend ~90% of their time indoors. Federal regulations generally focus on drinking water at the water treatment plant and within the distribution system as opposed to when it enters buildings after crossing the property line. If drinking water is not properly managed in buildings, it can be a source or amplifier of microbial and chemical contaminants. Unlike regulations for chemical contaminants that are risk-based, for pathogens, regulations are either based on recommended treatment technologies or designated as zero, which is not achievable in practice. Practice-based judgments are typically made at the building level to maintain water quality. This research focuses on two drinking water opportunistic pathogens of public health concern, Legionella pneumophila and Mycobacterium avium complex (MAC). Multiple aspects of drinking water quality in two green buildings were monitored in tandem with water management interventions. Additionally, a quantitative microbial risk assessment framework was used to predict risk-based critical concentrations of MAC for drinking water-related exposures in the indoor environment corresponding to a 1 in 10,000 annual infection target risk benchmark. The overall goal of this work was to inform the development of water management plans and guidelines for buildings that will improve water quality in the built environment and promote better public health. It was determined that a whole building water softening system with ion exchange softening resin and expansion tanks were unexplored reservoirs for the colonization of L. pneumophila. Furthermore, it was observed that typical water management interventions such as flushing and thermal disinfection did not always mitigate water quality issues. Thus, there was a need to implement several atypical interventions such as equipment replacement to improve the building water quality. This work has contributed comprehensive field studies and models that have highlighted the need for additional niches, facility management challenges, and risk tradeoffs for focus in water safety plans. The work also informs additional risk-based water quality policy approaches for reducing drinking water risks.
ContributorsJoshi, Sayalee (Author) / Hamilton, Kerry A (Thesis advisor) / Abbaszadegan, Morteza (Committee member) / Conroy-Ben, Otakuye (Committee member) / Halden, Rolf (Committee member) / Arizona State University (Publisher)
Created2023
Description

Synthetic plastics are ubiquitously used in a broad range of applications, including food and drink packaging. Plastics often contain chemical additives, including bisphenols, phthalates, and terephthalic acid, which can degrade under thermal stress. The environmental presence of these chemicals is cause for public concern, especially in consumer products that utilize

Synthetic plastics are ubiquitously used in a broad range of applications, including food and drink packaging. Plastics often contain chemical additives, including bisphenols, phthalates, and terephthalic acid, which can degrade under thermal stress. The environmental presence of these chemicals is cause for public concern, especially in consumer products that utilize plastic packaging, as many have been identified as endocrine disruptors. This study sought to determine exposure to phthalates, bisphenols, and terephthalic acid by quantifying a broad spectrum of these analytes within three bottled water brands at varying temperature exposure levels using the combination of solid phase extraction followed by isotope dilution liquid chromatography-tandem mass spectrometry. Monobenzyl phthalate was detected in two of the three brands after bottles were heated to ~100 °C, ranging from 98 – 107 ng/L, and bisphenol A was detected in one brand at ~100 °C at an average concentration of 748 ± 36 ng/L. Subsequent mass loading calculations demonstrated that bioaccumulation of BPA from Brand C after high levels of temperature exposure well exceeded the tolerable daily intake (TDI). Findings in this study indicate that consumers should not be expected to incur harmful exposures to the target compounds under normal conditions as analytes were not measured in water bottle samples at 25 °C or 60 °C. Further studies should explore a more nuisance approach to heating over long durations, including that of ultraviolet exposure.

ContributorsZevitz, Jacob (Author) / Halden, Rolf (Thesis director) / Driver, Erin (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor)
Created2022-12
Description
The production and incineration of single-use micropipette tips and disposable gloves, which are heavily used within laboratory facilities, generate large amounts of greenhouse gasses (GHGs) and accelerate climate change. Plastic waste that is not incinerated often is lost in the environment. The long degradation times associated with this waste exacerbates

The production and incineration of single-use micropipette tips and disposable gloves, which are heavily used within laboratory facilities, generate large amounts of greenhouse gasses (GHGs) and accelerate climate change. Plastic waste that is not incinerated often is lost in the environment. The long degradation times associated with this waste exacerbates a variety of environmental problems such as substance runoff and ocean pollution. The objective of this study was to evaluate the efficacy of possible solutions for minimizing micropipette tip and disposable glove waste within laboratory spaces. It was hypothesized that simultaneously implementing the use of micropipette tip washers (MTWs) and energy-from-glove-waste programs (EGWs) would significantly reduce (p < 0.05) the average combined annual single-use plastic micropipette tip and nitrile glove waste (in kg) per square meter of laboratory space in the United States. ASU’s Biodesign Institute (BDI) was used as a case study to inform on the thousands of different laboratory facilities that exist all across the United States. Four separate research laboratories within the largest public university of the U.S. were sampled to assess the volume of plastic waste from single-use micropipette tips and gloves. Resultant data were used to represent the totality of single-use waste from the case study location and then extrapolated to all laboratory space in the United States. With the implementation of EGWs, annual BDI glove waste is reduced by 100% (0.47 ± 0.26 kg/m2; 35.5 ± 19.3 metric tons total) and annual BDI glove-related carbon emissions are reduced by ~5.01% (0.165 ± 0.09 kg/m2; 1.24 ± 0.68 metric tons total). With the implementation of MTWs, annual BDI micropipette tip waste is reduced by 92% (0.117 ± 0.03 kg/m2; 0.88 ± 0.25 metric tons total) and annual BDI tip-related carbon emissions are reduced by ~83.6% (4.04 ± 1.25 kg/m2; 30.5 ± 9.43 metric tons total). There was no significant difference (p = 0.06) observed between the mass of single-use waste (kg) in the sampled laboratory spaces before (x̄ = 47.1; σ = 43.3) and after (x̄ =0.070; σ = 0.033) the implementation of the solutions. When examining both solutions (MTWs & EGWs) implemented in conjunction with one another, the annual BDI financial savings (in regard to both purchasing and disposal costs) after the first year were determined to be ~$7.92 ± $9.31/m2 (7,500 m2 of total wet laboratory space) or ~$60,000 ± $70,000 total. These savings represent ~15.77% of annual BDI spending on micropipette tips and nitrile gloves. The large error margins in these financial estimates create high uncertainty for whether or not BDI would see net savings from implementing both solutions simultaneously. However, when examining the implementation of only MTWs, the annual BDI financial savings (in regard to both purchasing and disposal costs) after the first year were determined to be ~$12.01 ± $6.79 kg/m2 or ~$91,000 ± $51,200 total. These savings represent ~23.92% of annual BDI spending on micropipette tips and nitrile gloves. The lower error margins for this estimate create a much higher likelihood of net savings for BDI. Extrapolating to all laboratory space in the United States, the total annual amount of plastic waste avoided with the implementation of the MTWs was identified as 8,130 ± 2,290 tons or 0.023% of all solid plastic waste produced in the United States in 2018. The total amount of nitrile waste avoided with the implementation of the EGWs was identified as 32,800 ± 17,900 tons or 0.36% of all rubber solid waste produced in the United States in 2018. The total amount of carbon emissions avoided with the implementation of the MTWs was identified as 281,000 ± 87,000 tons CO2eq or 5.4*10-4 % of all CO2eq GHG emissions produced in the United States in 2020. Both the micropipette tip washer and the glove waste avoidance program solutions can be easily integrated into existing laboratories without compromising the integrity of the activities taking place. Implemented on larger scales, these solutions hold the potential for significant single-use waste reduction.
ContributorsZdrale, Gabriel (Author) / Mahant, Akhil (Co-author) / Halden, Rolf (Thesis director) / Biyani, Nivedita (Committee member) / Driver, Erin (Committee member) / Barrett, The Honors College (Contributor) / Harrington Bioengineering Program (Contributor)
Created2022-05
Description
The production and incineration of single-use micropipette tips and disposable gloves, which are heavily used within laboratory facilities, generate large amounts of greenhouse gasses (GHGs) and accelerate climate change. Plastic waste that is not incinerated often is lost in the environment. The long degradation times associated with this waste exacerbates

The production and incineration of single-use micropipette tips and disposable gloves, which are heavily used within laboratory facilities, generate large amounts of greenhouse gasses (GHGs) and accelerate climate change. Plastic waste that is not incinerated often is lost in the environment. The long degradation times associated with this waste exacerbates a variety of environmental problems such as substance runoff and ocean pollution. The objective of this study was to evaluate the efficacy of possible solutions for minimizing micropipette tip and disposable glove waste within laboratory spaces. It was hypothesized that simultaneously implementing the use of micropipette tip washers (MTWs) and energy-from-glove-waste programs (EGWs) would significantly reduce (p < 0.05) the average combined annual single-use plastic micropipette tip and nitrile glove waste (in kg) per square meter of laboratory space in the United States. ASU’s Biodesign Institute (BDI) was used as a case study to inform on the thousands of different laboratory facilities that exist all across the United States. Four separate research laboratories within the largest public university of the U.S. were sampled to assess the volume of plastic waste from single-use micropipette tips and gloves. Resultant data were used to represent the totality of single-use waste from the case study location and then extrapolated to all laboratory space in the United States. With the implementation of EGWs, annual BDI glove waste is reduced by 100% (0.47 ± 0.26 kg/m2; 35.5 ± 19.3 metric tons total) and annual BDI glove-related carbon emissions are reduced by ~5.01% (0.165 ± 0.09 kg/m2; 1.24 ± 0.68 metric tons total). With the implementation of MTWs, annual BDI micropipette tip waste is reduced by 92% (0.117 ± 0.03 kg/m2; 0.88 ± 0.25 metric tons total) and annual BDI tip-related carbon emissions are reduced by ~83.6% (4.04 ± 1.25 kg/m2; 30.5 ± 9.43 metric tons total). There was no significant difference (p = 0.06) observed between the mass of single-use waste (kg) in the sampled laboratory spaces before (x̄ = 47.1; σ = 43.3) and after (x̄ =0.070; σ = 0.033) the implementation of the solutions.When examining both solutions (MTWs & EGWs) implemented in conjunction with one another, the annual BDI financial savings (in regard to both purchasing and disposal costs) after the first year were determined to be ~$7.92 ± $9.31/m2 (7,500 m2 of total wet laboratory space) or ~$60,000 ± $70,000 total. These savings represent ~15.77% of annual BDI spending on micropipette tips and nitrile gloves. The large error margins in these financial estimates create high uncertainty for whether or not BDI would see net savings from implementing both solutions simultaneously. However, when examining the implementation of only MTWs, the annual BDI financial savings (in regard to both purchasing and disposal costs) after the first year were determined to be ~$12.01 ± $6.79 kg/m2 or ~$91,000 ± $51,200 total. These savings represent ~23.92% of annual BDI spending on micropipette tips and nitrile gloves. The lower error margins for this estimate create a much higher likelihood of net savings for BDI. Extrapolating to all laboratory space in the United States, the total annual amount of plastic waste avoided with the implementation of the MTWs was identified as 8,130 ± 2,290 tons or 0.023% of all solid plastic waste produced in the United States in 2018. The total amount of nitrile waste avoided with the implementation of the EGWs was identified as 32,800 ± 17,900 tons or 0.36% of all rubber solid waste produced in the United States in 2018. The total amount of carbon emissions avoided with the implementation of the MTWs was identified as 281,000 ± 87,000 tons CO2eq or 5.4*10-4 % of all CO2eq GHG emissions produced in the United States in 2020. Both the micropipette tip washer and the glove waste avoidance program solutions can be easily integrated into existing laboratories without compromising the integrity of the activities taking place. Implemented on larger scales, these solutions hold the potential for significant single-use waste reduction.
ContributorsMahant, Akhil (Author) / Zdrale, Gabriel (Co-author) / Halden, Rolf (Thesis director) / Biyani, Nivedita (Committee member) / Driver, Erin (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / School of Life Sciences (Contributor)
Created2022-05
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Description

Diabetes affects millions of people globally and can lead to other severe health complications when undiagnosed or not properly managed. The incidence of diabetes has rapidly increased over the past several years, however, not all individuals have access to affordable or convenient healthcare. We hypothesize that wastewater-based epidemiology (WBE) has

Diabetes affects millions of people globally and can lead to other severe health complications when undiagnosed or not properly managed. The incidence of diabetes has rapidly increased over the past several years, however, not all individuals have access to affordable or convenient healthcare. We hypothesize that wastewater-based epidemiology (WBE) has the potential to assess community health status by analyzing biomarkers indicative of human health and disease, including diabetes. Used in tandem with current methods, monitoring indicators of diabetes in community wastewater could provide a comprehensive assessment tool for disease prevalence in large and small populations. Specifically, the proposed targeted biomarker evaluated in this study to indicate population-wide diabetes prevalence was 8-hydroxy-2’- deoxyguanosine (8-OHdG). This work combines a rigorous literature review and initial laboratory studies to explore the possibility of diabetes monitoring at the community level using WBE. Here, 24-hour composite wastewater samples were collected from within two wastewater sub-catchments of Greater Tempe, AZ. Overall goals of this study were to: i) Determine the feasibility to detect endogenous markers of diabetes in community wastewater; ii) Assess the potential impact of confounding factors, such as smoking, cancer, and atherosclerosis, through a literature analysis; and iii) Evaluate the socioeconomic status and demographics of the study population. Preliminary results of the experiments suggest this methodology to be feasible, as indicated by the observation of detectable signals of 8-OHdG in community wastewater collected from the sewer infrastructure; however, future work and continued experimentation will be required to address low signal intensity and assay precision and accuracy. Thus, the work presented here provides valuable proof-of-concept data, with detailed information on the method employed and identified opportunities to further determine the relationship between 8-OHdG concentrations in municipal wastewater and diabetes prevalence at the community level.

ContributorsNguyen, Jasmine (Author) / John, Dona (Co-author) / Halden, Rolf (Thesis director) / Driver, Erin (Committee member) / Bowes, Devin (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor) / Dean, W.P. Carey School of Business (Contributor) / Department of Finance (Contributor)
Created2022-05
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Description

Diabetes affects millions of people globally and can lead to other severe health complications when undiagnosed or not properly managed. The incidence of diabetes has rapidly increased over the past several years, however, not all individuals have access to affordable or convenient healthcare. We hypothesize that wastewater-based epidemiology (WBE) has

Diabetes affects millions of people globally and can lead to other severe health complications when undiagnosed or not properly managed. The incidence of diabetes has rapidly increased over the past several years, however, not all individuals have access to affordable or convenient healthcare. We hypothesize that wastewater-based epidemiology (WBE) has the potential to assess community health status by analyzing biomarkers indicative of human health and disease, including diabetes. Used in tandem with current methods, monitoring indicators of diabetes in community wastewater could provide a comprehensive assessment tool for disease prevalence in large and small populations. Specifically, the proposed targeted biomarker evaluated in this study to indicate population-wide diabetes prevalence was 8-hydroxy-2’-deoxyguanosine (8-OHdG). This work combines a rigorous literature review and initial laboratory studies to explore the possibility of diabetes monitoring at the community level using WBE. Here, 24-hour composite wastewater samples were collected from within two wastewater sub-catchments of Greater Tempe, AZ. Overall goals of this study were to: i) Determine the feasibility to detect endogenous markers of diabetes in community wastewater; ii) Assess the potential impact of confounding factors, such as smoking, cancer, and atherosclerosis, through a literature analysis; and iii) Evaluate the socioeconomic status and demographics of the study population. Preliminary results of the experiments suggest this methodology to be feasible, as indicated by the observation of detectable signals of 8-OHdG in community wastewater collected from the sewer infrastructure; however, future work and continued experimentation will be required to address low signal intensity and assay precision and accuracy. Thus, the work presented here provides valuable proof-of-concept data, with detailed information on the method employed and identified opportunities to further determine the relationship between 8-OHdG concentrations in municipal wastewater and diabetes prevalence at the community level.

ContributorsJohn, Dona (Author) / Nguyen, Jasmine (Co-author) / Halden, Rolf (Thesis director) / Driver, Erin (Committee member) / Bowes, Devin (Committee member) / Barrett, The Honors College (Contributor) / School of Molecular Sciences (Contributor) / Department of Psychology (Contributor)
Created2022-05
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Currently, there are a number of studies confirming the link between exposure to certain chemicals, notably pesticides (Costello et. al. 2009, Wang et. al 2014), heavy metals such as arsenic (Chen et. al. 2017), ambient air pollution (Chen et. al. 2016), and chemicals specific to certain industrial fields (Nielsen et.

Currently, there are a number of studies confirming the link between exposure to certain chemicals, notably pesticides (Costello et. al. 2009, Wang et. al 2014), heavy metals such as arsenic (Chen et. al. 2017), ambient air pollution (Chen et. al. 2016), and chemicals specific to certain industrial fields (Nielsen et. al. 2021). However, few papers have attempted to perform a widespread analysis of the factors associated with Parkinson’s disease to identify whether the risk of developing the disease is dependent on different factors regionally. The goal of my thesis project is to complete a meta-analysis of toxins- where exposure may occur in both residential and occupational settings- that are associated with Parkinson’s to determine such regional differences and to identify any gaps in current literature, which may direct the course of future research in the field. As seen in this paper, it appears that occupational exposure to toxins appears to have the greatest impact on the risk of developing Parkinson’s disease, particularly pesticides and industrial toxins. However, there are numerous gaps with regards to data collection, regions studied, and quantification of toxin concentrations. However, this data may be useful in identifying at-risk populations if more extensive incremental and biopsy data regarding these toxins is provided.

ContributorsAravindan, Anumitha (Author) / Halden, Rolf (Thesis director) / Driver, Erin (Committee member) / Newell, Melanie (Committee member) / Barrett, The Honors College (Contributor) / School of Life Sciences (Contributor)
Created2022-05
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Description
Heavy metals and persistent organic pollutants contribute to human health risks worldwide. Among the most common routes of exposure to pollutants for humans are through the consumption of contaminated water and food, with fish being among the greatest vectors for ingestion of heavy metals in humans, particularly mercury.This dissertation consists

Heavy metals and persistent organic pollutants contribute to human health risks worldwide. Among the most common routes of exposure to pollutants for humans are through the consumption of contaminated water and food, with fish being among the greatest vectors for ingestion of heavy metals in humans, particularly mercury.This dissertation consists of three chapters with a central theme of investigating heavy metal and persistent organic pollutant concentrations in fish and corned beef, which are two commonly consumed food items in American Samoa. A literature review illustrated that historically the primary pollutants of concern in fish muscle tissue from American Samoa have been mercury, arsenic, and polycyclic aromatic hydrocarbon mixtures. To better understand the changes in heavy metals and persistent organic pollutants in fish, this study reports an updated data set, comparing concentrations in pollutants as they have changed over time. To further investigate pollutants in fish tissue, 77 locally caught and commonly consumed fish were analyzed for heavy metals and persistent organic pollutants, and baseline human health risk assessments were calculated for contaminants that had available oral reference doses. While in American Samoa collecting fish for contaminant analyses, it was realized that canned corned beef appeared to be more commonly consumed than fresh fish. An IRB approved consumption survey revealed that 89% of American Samoan adults regularly consume fish, which is the same percentage of people that reported eating canned corned beef, indicating a dramatic increase in this food item to their diet since its introduction in the 20th century. Results of this study indicate that fish muscle tissue generally has higher heavy metal concentrations than canned corned beef, and that mercury continues to be a main contaminant of concern when consuming fresh and canned fish in American Samoa. While none of the heavy metal concentrations in corned beef exceeded calculated action levels, these foods might contribute to negative health outcomes in other ways. One of the main findings of this study is that either the presence or the ability to detect persistent organic pollutant concentrations are increasing in fish tissue and should be periodically monitored to adequately reflect current conditions.
ContributorsLewis, Tiffany Beth (Author) / Polidoro, Beth (Thesis advisor) / Neuer, Susanne (Thesis advisor) / Halden, Rolf (Committee member) / Schoon, Michael (Committee member) / Arizona State University (Publisher)
Created2023
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Description
This work focuses on a novel approach to combine electrical current with cyanobacterial technology, called microbial electrophotosynthesis (MEPS). It involves using genetically modified PSII-less Synechocystis PCC 6803 cells to avoid photoinhibition, a problem that hinders green energy. In the work, a cathodic electron delivery system is employed for growth and

This work focuses on a novel approach to combine electrical current with cyanobacterial technology, called microbial electrophotosynthesis (MEPS). It involves using genetically modified PSII-less Synechocystis PCC 6803 cells to avoid photoinhibition, a problem that hinders green energy. In the work, a cathodic electron delivery system is employed for growth and synthesis. Photoinhibition leads to the dissipation energy and lower yield, and is a major obstacle to preventing green energy from competing with fossil fuels. However, the urgent need for alternative energy sources is driven by soaring energy consumption and rising atmospheric carbon dioxide levels. When developed, MEPS can contribute to a carbon capture technology while helping with energy demands. It is thought that if PSII electron flux can be replaced with an alternative source photosynthesis could be enhanced for more effective production. MEPS has the potential to address these challenges by serving as a carbon capture technology while meeting energy demands. The idea is to replace PSII electron flux with an alternative source, which can be enhanced for higher yields in light intensities not tolerated with PSII. This research specifically focuses on creating the initiation of electron flux between the cathode and the MEPS cells while controlling and measuring the system in real time. The successful proof-of-concept work shows that MEPS can indeed generate high-light-dependent current at intensities up to 2050 µmol photons m^‒2 s^‒1, delivering 113 µmol electrons h^‒1 mg-chl^‒1. The results were further developed to characterize redox tuning for electron delivery of flux to the photosynthetic electron transport chain and redox-based kinetic analysis to model the limitations of the MEPS system.
ContributorsLewis, Christine Michelle (Author) / Torres, César I (Thesis advisor) / Fromme, Petra (Thesis advisor) / Woodbury, Neal (Committee member) / Hayes, Mark (Committee member) / Arizona State University (Publisher)
Created2023
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Description

The COVID-19 pandemic caused uncertainty and changing public health recommendations across the world as our understanding of the SARS-CoV-2 virus changed. Following a preliminary assessment by the World Health Organization, non-steroidal anti-inflammatory drugs were said to worsen symptoms and should be avoided before the recommendation was subsequently revoked. There also

The COVID-19 pandemic caused uncertainty and changing public health recommendations across the world as our understanding of the SARS-CoV-2 virus changed. Following a preliminary assessment by the World Health Organization, non-steroidal anti-inflammatory drugs were said to worsen symptoms and should be avoided before the recommendation was subsequently revoked. There also was pain associated with infection, leading to the hypothesis that use of over-the-counter pain medication increases may correlate with increases of SARS-CoV-2 infections. Wastewater samples were collected from two communities in Tempe, AZ from December 2019 to July 2020 (n = 35) and were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) to identify levels of acetaminophen, ibuprofen and their metabolites, acetaminophen sulfate and carboxy-ibuprofen. Results showed 100% detection frequency of all analytes in all samples across the duration of the study. Mass loadings of acetaminophen (918.4 g day-1 +/- 354.8 g day-1) were higher than ibuprofen (182.9 g day-1 +/- 49.8 g day-1), potentially driven by flushing behaviors rather than consumption activities. However, ibuprofen was more heavily consumed than acetaminophen across all days of the study period. Comparisons to COVID-19 clinical cases data showed increased use in ibuprofen with increases in clinical cases loads, while acetaminophen showed no change, suggesting ibuprofen was the over the counter (OTC) medication of choice during the first wave of the pandemic.

ContributorsSavic, Sonja (Author) / Halden, Rolf (Thesis director) / Driver, Erin (Committee member) / Barrett, The Honors College (Contributor) / School of Sustainability (Contributor) / School of Life Sciences (Contributor)
Created2022-05