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The nature of the oil and rough seas contributed to the rapid formation of a
"chocolate mousse" emulsification of oil and water.  This viscous emulsification
greatly complicated the cleanup efforts.  French authorities decided not to use
dispersants in sensitive areas or the coastal fringe where water depth was less
than 50 meters.  Had dispersant been applied from the air in the vicinity of the
spill source,  the formation of mousse may have been prevented.

At the time, the Amoco Cadiz  incident resulted in the largest loss of marine
life ever recorded from an oil spill.  Mortalities of most animals occurred over
the two month period following the spill.  Two weeks following the accident,
millions of dead mollusks, sea urchins, and other bottom dwelling organisms
washed ashore.  Diving birds constituted the majority of the nearly 20,000 dead
birds that were recovered.  The oyster mortality from the spill was estimated at
9,000 tons.  Fishes with skin ulcerations and tumors were caught by fishermen in
the area.  Some of the fish caught in the area reportedly had a strong taste of
petroleum.  Although echinoderm and small crustacean populations almost
completely disappeared, the populations of many species recovered within a year.
 Cleanup activities on rocky shores, such as pressure-washing, also caused
habitat impacts.

The Amoco Cadiz spill was one of the most studied oil spills in history.  Many 
studies remain in progress.  This was the largest recorded spill in history and
was the first spill in which estuarine tidal rivers were oiled.  No follow-up
mitigation existed to deal with asphalt formation and problems that resulted
after the initial aggressive cleanup.  Addition erosion of beaches occurred in
several places where no attempt was made to restore the gravel that was removed
to lower the beach face.  Many of the affected marshes, mudflats, and sandy
beaches, were low-energy areas.  Evidence of oiled beach sediments can still be
seen in some of these sheltered areas.  Layers of sub-surface oil still remain
buried in many of the impacted beaches.