Volcanic air pollution over the Island of Hawai'i: Emissions, dispersal, and composition. Association with respiratory symptoms and lung function in Hawai'i Island school children

Environmental data suggested 4 different vog exposure zones with SO2, PM2.5, and particulate acid concentrations (mean ± s.d.) as follows: 1) Low (0.3 ± 0.2 ppb, 2.5 ± 1.2 μg/m3, 0.6 ± 1.1 nmol H +/m3), 2) Intermittent (1.6 ± 1.8 ppb, 2.8 ± 1.5 μg/m3, 4.0 ± 6.6 nmol H +/m3), 3) Frequent (10.1 ± 5.2 ppb, 4.8 ± 1.9 μg/m3, 4.3 ± 6.7 nmol H +/m3), and 4) Acid (1.2 ± 0.4 ppb, 7.2 ± 2.3 μg/m3, 25.3 ± 17.9 nmol H +/m3). Participants (1957) in the 4 zones differed in race, prematurity, maternal smoking during pregnancy, environmental tobacco smoke exposure, presence of mold in the home, and physician-diagnosed asthma. Multivariable analysis showed an association between Acid vog exposure and cough and strongly suggested an association with FEV1/FVC < 0.8, but not with diagnosis of asthma, or chronic persistent wheeze or bronchitis in the last 12 months. Conclusions: Hawai'i Island's volcanic air pollution can be very acidic, but contains few co-contaminants originating from anthropogenic sources of air pollution. Chronic exposure to acid vog is associated with increased cough and possibly with reduced FEV1/FVC, but not with asthma or bronchitis. Further study is needed to better understand how volcanic air pollution interacts with host and environmental factors to affect respiratory symptoms, lung function, and lung growth, and to determine acute effects of episodes of increased emissions.