This article reports estimates of the level of CO 2 emissions created by Formula One (F1) cars on Sunday races. Supported by a variety of sources and using Monte Carlo iterations, we obtained values identifying important periods of change. These periods were identified using tests of structural breaks. We observe that the 1966-1970 period (related to the dominance of DFV/Cosworth engines) is associated with an increase in CO 2 emissions, whereas the 1992-1995 period (related to lighter and more efficient engines) is associated with a decrease in estimated levels of emitted CO 2 . Our results do not identify the deep modifications following more "green" regulations in 2009-2011 as a relevant change.