Oh you've descended to using negative ratings and irrational assumptions about the opposition have you? Well, I can play along with that. You see, I don't usually demand logic. Some of the best RP's I've played in have had magic and all manner of crazy creatures. My problem here is that you use the term "evolve" and you attempt to explain this so called "evolution" using "pollution". Which is interesting in itself, but that's a scientific concept, something I doubt your tiny mind can grasp. I wouldn't have minded if you'd simply acknowledged that there was some kind of magical force involved, but instead you continued trying to use scientific reasoning that you can't even get right to explain it. This is the one that got me. It was damn hilarious.
"Now the logical reason is a mutation in their DNA. which would change them immediately."
Notice that your own arguments conflict with each other. On one hand you say it's fantasy and anything can happen and then in another post you think that a mutation in DNA would logically cause an instant change.
Now, lets look at the science shall we? A mutation in the genetic code of an animal or plant does not cause immediate change. Cancer is caused by a mutation. Mutations can only ever cause cancers in anything bigger than a single celled organism. They cannot cause it to grow huge or have a behavioral change. Thus, if a tiger were to mutate, it would simply become a tiger that had cancer, not a tiger that was really big and really violent. Or perhaps you were meaning that the DNA changes but only the offspring of the changed show the traits? This is more possible since it is how evolution occurs. However, evolution takes a stupidly long length of time, and in even the normal pregnancy cycle of a given animal, changes to the species could not possibly cause such change. A single offspring may have a slightly longer neck, at most, or a slightly darker shade of skin. Changing enough DNA to cause the creature to become an entirely new species would result in offspring that were unable to reproduce, thus every species would die out after 1 generation. And while we're on it, how come the humans haven't mutated? Especially considering they're the ones that live closest to the pollution.
And while I'm criticising you, you may want to take a look at your grammar. You can't get the right version of "your", you use 2 punctuation marks after each other, you capitalise random letters, and you can't work out when things need to be plural. Then you go and write a sentence that doesn't even make sense, in this context: "in fantasy Role-play anything can be impossible". You trail off the end of sentences when your own arguing skills fail to support your case too: "Its a freaking Fantasy Role-play but from the looks of it you don't even know what fantasy means since -.-/". Hey look another nonsensical sentence: "Anyway since your so obssessed with logic then this Rp isn't for you or any fantasy one". Your spelling skills could do with improvement too. Oh and misuse of "their" "And their are some city who still stand." That one also has an example of not using a plural where it is needed. Also, it's more grammatically correct to use "that" rather than "who". You could probably benefit from using the "edit" button too. Making a new post for every couple of sentences makes you look childish.
TL;DR Next time you make magical settings, don't try and use science to explain them.