One of your problems stems from your loose use of language. You have not defined pollutant. Generally, nitrogen dioxide and sulfur dioxide, for example, are considered pollutants, but regarding what? I am sure you are aware of the fact that there are many organisms which thrive in the presence of sulfur, and would die instantly if exposed to oxygen. Sulfur is not a pollutant for these creatures, yet oxygen is. Skill testing question, if oxygen goes above a certain level in the atmosphere, will it become a pollutant re: humans? What concentration might that be? Is it proper to talk of oxygen as a pollutant? Potential pollutant? Should we ban any equipment that does/might add to the concentration of oxygen in the atmosphere? Further, the whole issue of pollutants has been politicized, and you seem to have fallen for it. Yes, certain legislation has listed C02 as a pollutant, but this is not a scientific reality. It is man made political science, (worse yet politically correct science) and, as such, nonsense. Do yourself a favor and try to think more critically and stop falling for the tripe the politicians are trying to shove down your throat. Are you not tired of being played for an useful idiot? See Stalin on this.