Wow, I wasn't expecting such a quick answer! Thank you very much John, this is golden information- i'll have a look at the book, we might have it in our library.
I am hoping to find a suitable polluted area on which I can base my reaserch. I might have to do it under lab conditions if for some reason I am not able to find a suitable area, but hopefully it won't be the case
So glad I found this place, it'll be very useful to me.
Also please excuse any errors, english isn't my mother tongue!