Chinese who live north of the Huai River will lose an aggregate 2.5 billion years of life expectancy due to the extensive use of coal burning in the region, concludes a new study published in Proceedings of the National Academy of Sciences. The study, which involved researchers from MIT, China, and Israel, estimated the impacts of particulate matter from coal-powered heating on life expectancy. In the process, the authors developed a rule-of-thumb for the effects of air pollution: “every additional 100 micrograms of particulate matter per cubic meter in the atmosphere lowers life expectancy at birth by three years,” according to a statement from MIT.