Utilizing wastewater-based epidemiology to assess the chemical exposome of residents in Louisville, Kentucky Restricted; Files Only
Byun, Justin (Spring 2024)
Abstract
Exposure to chemicals has become an inescapable reality, with increasing evidence showing that environmental exposures are linked to non-communicable diseases among residents of high-income countries. There has been an increase in cases of chronic diseases that may be attributable to environmental exposures among the last decade. With the need for a more complete environmental exposure assessment to understand the association between environmental influences and their biological response, wastewater-based epidemiology holds potential to identify the chemical exposome without requiring individual samples from a study population, avoiding the costly and logistical constraints of human biomonitoring of biofluids.
The purpose of this study was to optimize and validate a solid phase extraction (SPE) method to prepare wastewater samples for untargeted screening using liquid chromatography-high resolution mass spectrometry (LC-HRMS) and compare wastewater exposome profiles from low to high socioeconomic neighborhoods, by population, sewershed area, and between residential and commercial areas to evaluate potential exposure disparities. We evaluated how SPE can enhance determination of the composition of analytes in wastewater and potentially identify previously unrecognized exposures for a more comprehensive chemical exposome profile.
Conducted in Louisville, Kentucky, which exhibits both industrial and residential areas, and a significant socioeconomic disparity between the west and east sides of the city, samples from 27 wastewater sites from both water quality treatment centers and sewershed areas leading to such centers were collected and analyzed by LC-HRMS.
SPE significantly increased the intensity of detected features in wastewater and the total number of detected features in wastewater compared to traditional sample preparation methods. Each site exhibited a larger number of detected features in wastewater prepared through SPE compared to wastewater prepared with traditional methods. However, no association was found between feature count and household income, population, and sewershed area of the wastewater sites. Features were annotated through xMSannotator, and the top five most concentrated chemicals detected in SPE wastewater, which was run on C18pos mode, were reported. This study demonstrated that untargeted analysis of exposure with annotation of detected features can detect previously known and potentially harmful exposures and delve further into problems of environmental injustice.
Table of Contents
Background 1
Methods 7
Study Site 7
Figure 1 8
Table 1 8
Sample Collection 13
Sample Preparation 13
Sample Extraction 13
Liquid Chromatography with HRMS 15
Data Processing 15
Data Analysis 16
Results 17
Figures 22
Discussion 36
Limitation 37
Next Steps 38
Conclusion 38
Appendix 40
Opentrons Method 40
Solid Phase Extraction Protocol for Wastwater 43
References 47
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File download under embargo until 24 November 2024 | 2024-04-09 18:00:09 -0400 | File download under embargo until 24 November 2024 |
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