"Or take sea-faring ships, who dump both grey and black water (ie. untreated sewage) into the sea; I understand this is slowly being subject to some regulation. "
Some? Some? Talk to a sailor about that one. The coast guard does not screw around with that at least in territorial waters and what exactly can be dumped where is highly regulated.
I wouldn't worry about the untreated sewage, after all, a lot of fish poop in the sea every day. The city I work in has determined its cheaper to pay EPA fines and dump raw sewage right off shore every time it rains, rather than make the substantial civil engineering investments to fix the system. I'd worry more about dish washing detergents and cooking oils and the like, unlike plain old sewage, the environment has very little natural experience with that kind of stuff.
Some? Some? Talk to a sailor about that one. The coast guard does not screw around with that at least in territorial waters and what exactly can be dumped where is highly regulated.
I wouldn't worry about the untreated sewage, after all, a lot of fish poop in the sea every day. The city I work in has determined its cheaper to pay EPA fines and dump raw sewage right off shore every time it rains, rather than make the substantial civil engineering investments to fix the system. I'd worry more about dish washing detergents and cooking oils and the like, unlike plain old sewage, the environment has very little natural experience with that kind of stuff.