The same sort of historical arch is not present in other fields of external costs, including climate change. While this history of research and regulation makes local and regional air pollution one of the most recognisable types of external costs from electricity provision, research continues. In particular, epidemiologists have begun looking at the various components of PM10 and PM25 as these components have been shown to have differential health damages and lifetimes in the atmosphere. Chronic effect deaths are between 88% and 99% of the total.