Acute respiratory effects associated with elevated vog emissions from Kilauea Volcano, Hawai`i

Background: Emissions of sulfur dioxide (SO₂) and sulfate particles called “vog” have vented for 28 years from the Kilauea Volcano, Hawai`i. In 2008, eruption activity increased resulting in a 3-fold higher exposure of vog pollution on a downwind community. This public health nursing study investigated acute respiratory effects in the population associated with the higher exposure. Methods: A retrospective cohort design compared prevalence of acute respiratory tract illnesses for the preceding 6 months of low vog exposure to prevalence for 6 months of high vog exposure during Kilauea's increased activity. All patient visits (N = 2,185) at the community clinic were reviewed for diagnostic accuracy, symptomology and demographical information. Effect was estimated by the odds ratio (OR) using a 95% confidence interval (CI) of the point estimates for significance testing. Logistic regression analysis adjusted the OR for a priori-selected potential confounders. Results: There were significant positive associations between high vog exposure and increased prevalence of acute airway problems (OR=2.80; 95% CI=1.49, 5.26), pharyngitis (OR=1.65; 95% CI=1.03, 2.64), bronchitis (OR=2.10; 95% CI=1.03, 4.27), and cough (OR=1.66; 95% CI=1.29, 2.14). The youngest patients experienced airway problems observed as tachypnea, shortness of breath, abnormal lung sounds, or de-saturated oxygen levels and responded to immediate therapies of oxygen or inhaled medications. Conclusions: These findings show an acute respiratory disease burden associated with vog and SO₂ exposure above the World Health Organization's 24-hour guideline and the Environmental Protection Agency's 2010 SO₂ 1-hour standard. Public health nursing has increased health prevention initiatives for the vog-exposed community.