I just found that the 16 largest Ships emit as much as all cars. Did not check the source further.
But that really depends on how you measure and define pollution. As others have pointed out container ships are still pretty efficient. But of course they should get better too. Like everything!
As I have said, I did not fact check it further because it is quite late here. Just wanted to give information to that claim and please correct your statement (:
It is really sad that Patrick Breyer will no longer be part of the European Parliament. His work was very important. I can also really recommend the 37C3 video!