Air Quality Risks in Public Housing

Importance: Public housing residents face elevated environmental health risks, yet indoor air quality in these settings remains underexamined. Objective: To evaluate indoor air quality in public housing 5 years after implementation of the federal smoke-free housing policy and compare it with outdoor air quality in the same regions. Design, Setting, and Participants: A 1-year cohort study of indoor air quality (particulate matter ≤2.5 μm in diameter [PM2.5]) across 12 multifamily public housing communities in southeastern Virgina for individuals 65 years and older or persons with disability in cities with the highest rated outdoor air quality. Indoor PM2.5 was continuously measured using 117 air quality monitors in shared common spaces and hallways of buildings. Outdoor data were obtained from 3 nearby Environmental Protection Agency (EPA) monitoring stations. Data were collected from January 1 to December 31, 2023. Exposure: Federal smoke-free housing policy implemented in 2018 aimed at reducing indoor pollution from tobacco smoke. Main Outcomes and Measures: Daily PM2.5 concentrations indoors and outdoors classified using EPA-defined risk categories. A repeated-measures linear mixed model was used to assess daily concentration differences over the 1-year study timeframe. Results: In this study of 12 public housing communities, indoor PM2.5 levels were significantly higher than outdoor levels (mean indoor PM2.5, 23.33 μg/m3; 95% CI, 21.85-24.81 μg/m3; mean outdoor PM2.5, 8.42 μg/m3; 95% CI, 5.49-11.35 μg/m3; P < .001), with 95% of daily indoor readings in the moderate (PM2.5, 9.1-35.4 μg/m3) or worse EPA risk categories, while 69% of outdoor readings were classified as good (PM2.5, 0-9 μg/m3). Conclusions and Relevance: Results of this study suggest that, despite a strong outdoor air quality rating and a smoke-free housing policy, indoor air quality in public housing remains poor. The findings underscore the need for strong, multifaceted interventions to reduce indoor pollution and promote environmental health equity.