Garbage and Sewage Pollution

Garbage from ships can be deadly to marine life as oil or chemicals. Regulations for the Prevention of pollution by garbage from ships are contained in Annex V of MARPOL.

The greatest danger comes from plastic, which can float for years. Fish and marine mammals can in some cases mistake plastics for food and they can also become trapped in plastic ropes, nets, bags and other items - even such innocuous items as the plastic rings used to hold cans of beer and drinks together.

It is clear that a good deal of the garbage washed up on beaches comes from people on shore - holiday-makers who leave their rubbish on the beach, fishermen who simply throw unwanted refuse over the side - or from towns and cities that dump rubbish into rivers or the sea. But in some areas most of the rubbish found comes from passing ships which find it convenient to throw rubbish overboard rather than dispose of it in ports.

The discharge of raw sewage into the sea can create a health hazard, while in coastal areas, sewage can also lead to oxygen depletion and an obvious visual pollution - a major problem for countries with large tourist industries. The main sources of human-produced sewage are land-based - such as municipal sewers or treatment plants.

Regulations for the prevention of pollution by sewage are contained in Annex IV of MARPOL.