My whole take of the issue is that pollution exists, it is being dealt with, and that is all we can do.
If there really was chemtrails they would have, by now given the length of time of their supposed existence, had a deleterious effect on all of society. Any attorney filing suits for environmental damages, animal and human deaths, etc. (such as Erin Brockovich) would have surely picked up the cause and won the case by now.
That makes sense. Whatever chemical they are spraying would probably have been found and analyzed.
Isn't this sort of a moot point?
With or without chem trails, we are putting enough toxins in the air through factories, cars, crop dusters, jet fuel, etc., etc.... Unless they are spraying cyanide or some other biochemical agent into the air, there are far more pressing issues to worry about that have attainable solutions.
As for whether or not I believe in chem trails, I don't necessarily believe they exist, but I also wouldn't be surprised if there was some truth to it.
Regarding the 'clouds' that are often formed from jets and airliners, this can be scientifically validated as condensation which turns into ice crystals at that altitude and forms a lingering cloud. Whether or not this phenomenon occurs is a factor of air pressure, temperature, and altitude (also related to air pressure). It is not due to deliberate cloud seeding technology or chemicals (other than bi-products of combusted jet fuel).