Oil spills and tanker safety continue to be the focus of industry's attention following the Mega Borg accident off Texas. Boycott of U.S. mainland ports by the international tanker business is gaining momentum. Elf Aquitaine has followed Royal Dutch/Shell Group in banning its tankers from U.S. terminals. Two large independent operators, World-Wide Shipping and A.F. Moller, also are considering withdrawing from the U.S. trade.