A friend wrote me that reading about pollution made her angry. I know I've written many times before about anger, but I'll do it again.
What struck me, as I though about her anger, is that two things have happened. One is that there is mercury in the ocean that has become part of the fish that we eat. I first became aware of the effects of mercury from the Minamata photos by Eugene Smith. The second thing that has happened is that someone is angry because there is mercury in the ocean.
Many say that the anger is good because it leads to attempts to clean up the environment. But who cleans up the anger, which is a kind of pollution itself? Is it necessary to be angry to act? You see a speeding car coming toward a kid in the street. Do you need to be angry to pull the kid from its path?
Here's a good link on anger, with quotes from the Buddha and the Bible.