MARPOL is the 1973 convention that established international rules for preventing pollution from ships.
The International Convention for the Prevention of Pollution from Ships was adopted under the auspices of the International Maritime Organization in 1973. The 1978 Protocol followed a series of tanker accidents, and the combined instrument is commonly called MARPOL 73/78. It entered into force in 1983.
MARPOL addresses pollution from ships caused by both routine operations and accidents. Its annexes regulate oil, noxious liquid substances carried in bulk, harmful substances in packaged form, sewage, garbage and air pollution. Special areas receive stricter controls because of their environmental sensitivity.
MARPOL is important to global trade because merchant ships carry most internationally traded goods by volume. It is different from SOLAS, which chiefly concerns maritime safety, and from UNCLOS, the broad UN convention governing the law of the sea. Compliance is implemented through flag states, port-state inspections and technical requirements for ships.