Much ado and attention has been paid to the pollutants emmitted from the tail pipes of cars and trucks in recent years, both here in the U.S. and across the pond in Europe. With an estimated 250 million passenger vehicles in the U.S. alone, it would seem that cars would be a major contributor to pollution and air quality issues here and abroad. But newly released data from Europe suggests that a single container ship may cause as much pollution as 50 million cars and release as much as 5,000 tons of sulfur oxide into the air annually. And there are 90,000 such ships of varying sizes across the world at any one time.