Socioeconomic determinants of indoor air pollution exposure from household cleaning chemicals

Abstract

Indoor air pollution represents a significant but insufficiently addressed dimension of environmental inequality, particularly concerning household cleaning chemicals. While research has largely focused on outdoor emissions, people spend most of their time indoors, where exposure to volatile organic compounds (VOCs) and fine particulate matter (PM₂.₅) is influenced by socioeconomic conditions, housing quality, and regulation. This study examines how socioeconomic status (SES) structures disparities in indoor air pollution exposure from cleaning chemicals across five regions: the United States, aggregated Europe, India, the Gulf States, and South Korea. Treating these regions as subpopulations within a unified framework, the study evaluates whether lower SES is systematically associated with higher exposure and greater health risks. The analysis integrates emission proxies from the Emissions Database for Global Atmospheric Research (EDGAR), including VOC speciation and PM₂.₅ emissions linked to cleaning products, with socioeconomic, household, and health-burden proxy variables from international datasets. Results reveal persistent vertical inequalities within countries and horizontal inequalities across regulatory contexts. Lower-income households are disproportionately exposed due to reliance on higher-emission products, constrained ventilation, crowded living conditions, and limited access to mitigation. A focused case study of South Korea’s post-2012 regulatory reforms following the humidifier disinfectant disaster illustrates how governance failures shape exposure risks. Scientifically, this study advances indoor air pollution research by embedding inequality and regulatory dimensions into cross-regional exposure assessment. From a policy perspective, the findings highlight the need for harmonized chemical regulation, transparent labeling, and affordability-driven interventions to reduce inequality and protect vulnerable populations globally and equitably, sustainably.