Documentation > Greenhouse effect > Greenhouse gases : what are they ? > Is it legitimate to say that carbon dioxide is a poison?
What is a poison ?
The dictionnary says: poison : any substance that, introduced in a living organism, can kill it or alterate its vital functions.
Of course the climate is not a living organism (!), even though a very interesting book explains that, "seen form Mars", it is tempting to consider Earth as a living being, given the number of homeostatic (homeostatic means self-regulating) functionsour planet includes. But the CO2 we now introduce into the atmosphere can definitely "kill", or at least "alterate", the vital functions of climate, that are to create a biosphere favorable to our own species.
It is therefore perfectly legitimate to state that greenhouse gas emissions of human origin constitute a poison, including CO2. That should lead not to consider as "clean" processes that "only" emit CO2, such as:
cars with catalytic exhausts
natural gas uses
any fuel cell that uses hydrocarbons