Harm from Residential Indoor Air Contaminants

Abstract

This study presents a health-centered approach to quantify and compare the chronic harm caused by indoor air contaminants using disability-adjusted life-year (DALY). The aim is to understand the chronic harm caused by airborne contaminants in dwellings and identify the most harmful. Epidemiological and toxicological evidence of population morbidity and mortality is used to determine harm intensities, a metric of chronic harm per unit of contaminant concentration. Uncertainty is evaluated in the concentrations of 45 indoor air contaminants commonly found in dwellings. Chronic harm is estimated from the harm intensities and the concentrations. The most harmful contaminants in dwellings are PM_2.5, PM_10-2.5, NO₂, formaldehyde, radon, and O₃, accounting for over 99% of total median harm of 2200 DALYs/10⁵ person/year. The chronic harm caused by all airborne contaminants in dwellings accounts for 7% of the total global burden from all diseases.

Keywords: DALY; acceptable indoor air quality; dwelling; harm budget; harm intensity; ranking.

Figure 1

Harm approach flow diagram.

Figure 2

Harm caused by CoCs. Median (bar) and GSD (error bar). Percentage contribution for total harm.

Figure 3

Representative airborne contaminant concentrations. Evaluation was performed against prior research. Median with GSD. Black, current work; green-triangle = Logue et al., blue-triangle = Fazli et al., red-triangle = Morawska et al.,^, cyan-triangle = Ilacqua et al., magenta-triangle = Nishihama et al., yellow-triangle = Ye et al., green-square, dashes = Vardoulakis et al., blue-square, and dashes = Halios et al.

Figure 4

Comparing chronic harm for the 10 most harmful contaminants against Logue et al. Median with GSD. Black, current work; blue, Logue et al.