The French National Assembly passed a bill last week to stiffen punishment for tanker captains who dump oil at sea in banned areas to clean their ship's tanks. The bill says captains of big tankers could be jailed for up to four years and fined up to $439,200. They had previously been liable to two years in prison and a $146,400 fine. Sanctions for captains of smaller tankers will be increased to two years in prison from one, with fines going up to $131,800 from $43,920. The bill still has to go through the Senate.