Concentrations of Polycyclic Aromatic Hydrocarbons (PAHs) in Personal and Cooking Area Air Samples from Rwandan Households and Influencing Factors
CLARA EICHLER, Joseph Pedit, Zachary G. Robbins, Ipsita Das, Karin Yeatts, Pamela Jagger, Sudhanshu Handa, Leena Nylander-French, University of North Carolina at Chapel Hill
Abstract Number: 331
Working Group: Aerosol Exposure
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are products of incomplete combustion associated with the burning of biomass fuels, including wood and charcoal commonly used for cooking in low-income countries. PAHs are major contributors to household air pollution and associated with adverse health outcomes. Here, we assessed the concentrations of EPA’s 16 priority PAHs in total air (gas/particle phase) samples collected using personal samplers worn by the cooks of 300 households in Gisenyi, Rwanda, in 2015, 2016, 2017, and 2019. In addition, total air was sampled in close proximity to the cooking areas at a subset of 110 households. Particulate matter (PM2.5) and carbon monoxide (CO) were measured and information on stove use, fuel types, and the cooking environment was collected. Samples were analyzed by gas chromatography-mass spectrometry (GC-MS). Across all four years of sampling and for both sample types, detection frequencies of the 16 PAHs ranged from 5-100%, with higher detection frequencies for lower molecular weight PAHs. No significant differences (p>0.05) between sampling years were observed for the concentrations of the sum of the 16 PAHs, ∑(PAH), for either sample type. However, ∑(PAH) concentrations were significantly lower in personal (median: 1.3 µg/m³, range: 0.061-69 µg/m³) compared to cooking area samples (3.2 µg/m³, 0.57-117 µg/m³). Concentrations were highest for naphthalene, which contributed on average 68% and 62% to ∑(PAH) concentrations in personal and cooking area samples, respectively. ∑(PAH) concentrations correlated moderately well with PM2.5 and CO concentrations (Spearman’s rho: 0.30-0.68), with stronger correlations for CO than for PM2.5. Biomass-burning stoves, including pellet stoves, were associated with significantly higher ∑(PAH) concentrations in both sample types compared to gas/electric stoves (personal: p=0.0002; cooking area: p=0.0009), emphasizing that a shift towards cleaner cooking technologies could reduce PAH exposures for household cooks.