Answer:
It's (capitalize and apostrophe) only a matter of time before environmental pollution is beyond our control. Pollution, which (delete) has been a growing problem for decades now. It poses numerous threats to our planet, (delete b/c comma before "including" is optional) including epidemics among humans and animals, ruined plants and vegetation, and obstructed scenery. To do your part in ending pollution. beyond our control, pollution, which has been a growing problem for decades (delete and correctly finish the sentence, "To do your part in ending pollution, ________" )
Very confusing question, I hope I did it right.