The negative consequences of long-term exposure to particulate pollution are well-established but many studies find no effect of short-term exposure on health outcomes. The high correlation of industrial pollutant emissions complicates the estimation of the impact of individual pollutants on health. In this study, we use emissions from Kilauea volcano, which are uncorrelated with other pollution sources, to estimate the impact of pollutants on local emergency room admissions and a precise measure of costs. A one standard deviation increase in particulates leads to a 23-36% increase in expenditures on ER visits for pulmonary outcomes, mostly among the very young. Even in an area where air quality is well within the safety guidelines of the U.S. Environmental Protection Agency, this estimate is larger than those in the existing literature on the short-term effects of particulates. No strong effects for cardiovascular outcomes are found.