Very nice composition. If this is the result of some kind of disaster though, it is kind of hard to see since the bg is so out of focus. Being of more of a documentary nature (if that is in fact your intention?), I think it should have a much larger dof.
There is good contrast here and the subject is nice...but that guy in the background is distracting. Instead of lookin at the flower and trash I'm just wondering what he's doin over there... Could use cropping but otherwise a really nice photograph.
I like the composition as it is but, for the sake of this specific challenge, more of a larger view should have been included in the composition to show what context you're projecting and a more concrete tie to the pollution theme