Question

How can carbon dioxide become harmful to the environment, as it is a breathing gas for our friends, PLANTS ?

Answer 1

Carbon dioxide becomes harmful to the environment, perhaps it is breathing gas for plants. But in the case of human beings and animals it acts like a poisonous gas, by directly inhaling CO2 gas we may get breathing problems, our lungs may get damage, if it happens so that it will increase very rapidly it may lead to extinction of living organisms on Earth, So that's the reason it is Harmful for us and as well as to the environment as it has lead to decrease of oxygen composition and polluting the environment.