DaimlerChrysler, Ford Motor Co. and General Motors captured three of the four top spots in a ranking of the worst polluters among the world's automakers.
But if the former Big 3 are the big polluters, they say it's because consumers continue to clamor for sport-utilities and light trucks, which are less fuel-efficient and produce more smog-forming emissions than passenger cars.
'We build a lot of trucks and SUVs because that's what people want to buy,' said Ford spokesman Terry Bresnihan.
'Of course, that's going to cause us to rank lower than manufacturers who build smaller cars.'
The rankings were released March 15 by the Union of Concerned Scientists, an independent, nonprofit environmental organization that evaluated 11 automakers. Isuzu Motors Ltd. was ranked the worst polluter, followed by DaimlerChrysler, Ford and GM.
Honda Motor Co. was ranked the cleanest of the car companies.
The rankings were based on fuel economy, air pollution and global warming emissions for 1998 model year vehicles sold in the United States.
Roland Hwang, the union's transportation program director, said automakers have concentrated on building bigger, more powerful vehicles rather than cleaner vehicles.
'Every manufacturer has the technology to improve the environmental performance of its sport-utility and light-truck fleet,' he said.
But Ford's Bresnihan said it cannot happen overnight. 'If we could build a 90 miles per gallon Explorer and not compromise the attributes consumers want,' he said. 'I think we'd do it.'
Sjoerd Dijkstra, a DaimlerChrysler spokesman, said the company's new generation of 2.7-, 3.2- and 3.5-liter engines for passenger cars and minivans all offer at least 10 percent better fuel economy and cut emissions.
'So we're on the forefront in changing to cleaner, more efficient engines,' he said.
But the ultimate choice is with consumers who predominantly choose bigger engines, he said.