Tracking Chemical Markers to Inform Population Health using Wastewater-based Epidemiology

This thesis focuses on applying wastewater-based epidemiology (WBE) to inform the population health status by studying antimicrobials, polymers, and mental health drugs (antidepressants, benzodiazepines, and Z-drugs) from community ranging in size (1600 to 481,420 people) in near real-time. First, an increasing mass trend of antimicrobials (1,431 ± 22 mg/day/1000 people) in wastewater was found in Arizona, with no evidence suggestive of the possible reintroduction of personal care products banned by the US Food and Drug Administration (FDA) ban during the pandemic (Chapter 2). Second, the use of mental health-related drugs (antidepressants, benzodiazepines, and Z-drugs) was estimated in community wastewater in the US and Mexico during the COVID-19 pandemic and compared against the prescription volume data obtained from the Medicaid database. Average mass consumption rates estimated using WBE ranged between 62 for Temazepam and 1,100 for Clonazepam in units of mg/day/1000 people in the United States. WBE data suggested an increase in Ketamine use (p < 0.05) during the COVID-19 pandemic (2020) relative to pre-pandemic time (2019). However, the volume of Ketamine uses as informed by prescription data did not increase suggesting illegal use of the drug might have increased during the COVID-19 pandemic (Chapter 3). I hypothesize that in addition to mental health drugs and antimicrobials, plastics also increase as a function of pandemic (Chapter 4). This necessitates an understanding of potential analytical challenges, which were investigated in Chapter 4 by conducting a literature review. An inventory of all the municipal wastewater treatment plants globally was created (Chapter 5). This study tabulated about107,000 in 129 countries serving 2.7 billion people (35% of the global population). This analysis suggests that about one-third of the world’s population could be reached by conducting WBE at centralized wastewater treatment plants. This dissertation demonstrates the utility of WBE in fields as diverse as tracking antimicrobials, substance misuse, and unsustainable materials such as plastics. WBE is broadly applicable to populations around the world to aide Sustainable Development Goals. The implementation of WBE in decision level from authority and stakeholders expedite the process of tracking community health against epidemic, infectious diseases and chemical exposure.