Well I must say I have been impressed by the pictures
However it is not sufficient to demostrate that some parameters changed because of pollution
The key question is :
What is their impact on the environment ?
I make a simple examples
If you go through medicine books of some years ago you can see that some parameters which nowdays are considered as normal were supposed to be extremely dangerous at the time
The point is that forcasts are extremely hard when you have to do with complex systems such as human body or environment
A statistical analysis is more reliable in these cases