Evaluating sources of volatile organic compounds in Colorado workplaces via positive matrix factorization

Abstract

Recognition of the health risks associated with exposure to volatile organic compounds (VOCs), particularly in indoor environments, has increased the need for a stronger understanding and management of air quality. Exposure to VOCs, emitted from various sources like building materials, office equipment, and consumer products, have been linked to both acute and chronic health outcomes, including respiratory issues and carcinogenic effects. While research on residential indoor air quality is extensive, fewer studies have characterized VOC exposure, particularly in workplaces, where people may spend a significant portion of their time. The work presented in this thesis addresses this knowledge gap through analysis of a comprehensive empirical study of VOC concentrations in 50 diverse workplaces across the State of Colorado. The study presented herein, which is part of a broader initiative led by Colorado State University in partnership with the Colorado Department of Public Health and Environment (CDPHE), utilized weeklong air sampling with SUMMA canisters and analyzed 61 target VOCs via EPA Method TO-15. Positive Matrix Factorization (PMF) modeling was employed to identify and apportion the sources of VOCs, providing insights into the relative contributions of indoor and outdoor pollutants. The findings inform further understanding of patterns of indoor VOCs measured in workplaces, as well as the design and implementation of targeted interventions to improve indoor air quality in occupational settings, particularly in underserved communities. Ultimately, this work contributes to advancing exposure science and supports healthier, and more sustainable indoor environments where people work.