Biological effects of marine oil pollution

Approximately 3.5 million tonnes of petroleum hydrocarbons enter the marine environment annually, either directly or indirectly from anthropogenic and natural, terrestrial, atmospheric and marine sources. This paper reviews available evidence on the biological consequences of such discharges and concludes that while effects are apparently not significant on a global scale, local catastrophes are a continuing reality.

In areas affected by oil slicks, local populations of invertebrates, birds and mammals may be greatly reduced and badly oiled vegetation may die. Particularly around the coast of the British Isles, whole populations of diving and gregarious birds are at risk. Generally, worst-affected organisms are those which inhabit shallow water and the littoral zone and those, such as marine mammals, which are obliged to cross the air-sea interface.

Special reference is made to vulnerable polar, salt-marsh, coral reef and mangrove habitats where biological effects of oil pollution may persist for decades. Effects on humans discussed range from dietary taste-tainting to theonomic costs of impaired recreational amenities. Possible risks from ingesting carcinogens in seafoods are outlined and a new research initiative in this area is recommended.