When it comes to mixing oil and water, oceans suffer from
far more than an occasional devastating spill. Disasters make headlines, but
hundreds of millions of gallons of oil quietly end up in the seas every year,
mostly from non-accidental sources §.
The graph below shows how many millions of gallons of oil each source puts into
the oceans worldwide each year
Down the Drain: 363 Million Gallons
Used engine oil can end up in waterways. An average oil change uses five quarts;
one change can contaminate a million gallons of fresh water. Much oil in runoff
from land and municipal and industrial wastes ends up in the oceans. 363 million
gallons §
Road runoff adds up
Every year oily road runoff from a city of 5 million could contain as much oil
as one large tanker spill §.
Routine Maintenance: 137 Million Gallons
Every year, bilge cleaning and other ship operations release millions of gallons
of oil into navigable waters, in thousands of discharges of just a few gallons
each. 137 million gallons §
Up in Smoke: 92 Million Gallons
Air pollution, mainly from cars and industry, places hundreds of tons of hydrocarbons
into the oceans each year. Particles settle, and rain washes hydrocarbons from
the air into the oceans §.
Natural Seeps: 62 Million Gallons
Some ocean oil "pollution" is natural. Seepage from the ocean bottom
and eroding sedimentary rocks releases oil.
Offshore Drilling: 15 Million Gallons
Offshore oil production can cause ocean oil pollution, from spills and operational
discharges §.
Accidents
Spills and slicks sicken and kill
Large spills--even though a relatively minor source of
ocean oil pollution--can be devastating. The same amount of oil can do more
damage in some areas than others. Coral reefs and mangroves are more sensitive
to oil than sandy beaches or sea-grass beds; intertidal zones are the most sensitive.
Crude oil is most likely to cause problems §.
Dead oiled otter
a victim of the Exxon Valdez spill Prince William Sound, 1989
NOAA scientist collects samples from a rock sole after an oil spill, 1989
Even if oil exposure isn't immediately lethal, it can
cause long-term harm.
Bottom-dwelling fish exposed to compounds released after
oil spills may develop liver disease and reproductive and growth problems.
photo Northwest Fisheries Science Center/National Oceanic and Atmospheric Administration
Mangroves stand in oil from a ruptured refinery tank,
Panama, 1986
Cleanups
Treaty treats pollution problems
International cooperation has greatly reduced accidental and operational oil
discharges from tankers. MARPOL (for MARine POLlution) is shorthand for a United
Nations treaty (the Convention for the Prevention of Pollution from Ships) that
became effective in 1983. MARPOL is largely credited for reducing oil pollution
from shipping by about 60 percent worldwide during the 1980s §.
More than half of all Americans change their own oil,
but only about one-third of the used oil from do-it-yourself oil changes is
collected and recycled. § Government and industry-sponsored oil collection
and recycling programs in many communities are increasing awareness of the hazards
of dumping used oil and the benefits of reusing it. §
Thousands of collection centers and service stations are
accepting used oil for recycling. To find out about recycling oil in your area,
contact your state environmental department or local recycling authority.
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