This topic is very interesting especially because even when leaded gasoline is no longer used, the damages and consequences to the environment and our life on the planet are really costly and alarming. The use of this gasoline beyond the ignorance of those who implemented it had to do with the campaign by the big oil industries that used this chemical component as a way to make more powerful and much more durable performance of the engines of vehicles even General Motors itself had to do in the use and popularity in their vehicles of this type of fuel which generated investigations that ended up being fixed with unconventional methods. But that is part of the history of pollution and human abuse of the planet, hopefully we can achieve a real transformation and ecological awareness but now the discussion is in the problems generated by the fuel used by spacecraft that venture into space tourism, perhaps our colleague @emiliomoron as a chemist or other of our brilliant talents of PH can explain how this new era will affect us.