It’s one of those dirty secrets that most cruise lines and transport lines have Liberian or Panamanian “flags” because they don’t require sewage treatment or most of the safety stuff that other nations require..Fortunately, American ships have not been allowed to dump their garbage for some decades. That doesn’t stop the Chinese or other nations, though..The real problem is bad enough, but some of the claims are ludicrous. Some idiots tried to claim that 20+ year old tires and decades-old plastics were floating around. Three problems with that: 1. Plastic breaks down quickly under the action of sunlight. A major problem on public lands is that the plastic containers of trash people dump come apart in a hurry from UV degradation, meaning you have to clean them up in a hurry. 2. Sulfate and salt action by seawater breaks down plastics and rubber very quickly. 3. Plastics with UV protection are recent. Older stuff breaks down much faster than some of the new consumer plastics. Even with UV protection, it still breaks down, though.
Mastroianni and Hart