1.   Complying with the ozone standard will be a tall order for both cities even with cleaner gasoline, he said.

2.   Critics accuse the companies of exaggerating the costs of marketing cleaner gasoline.

3.   Further, prices are often higher still in big cities like Chicago, where government requires cleaner gasoline as a pollution-control tool.

4.   Massachusetts has already mandated cleaner utilities, the use of cleaner gasoline, auto emissions testing and the sale of zero-emission electric vehicles, officials said.

5.   Oil refiners will have to make cleaner gasoline, too.

6.   Pump prices could edge up another nickel in January when retailers start selling a cleaner gasoline mandated by federal law.

7.   Rather than fighting the administration for less stringent emissions standards, the auto industry has allied itself with environmentalists in demanding cleaner gasoline.

8.   Scientists say Pemex must move more quickly, and openly, to make much cleaner gasoline for the capital all year round.

9.   The administration is also facing a revolt from many cities and states over the requirements for greater use of reformulated fuels, or cleaner gasoline.

10.   The cleaner gasoline would mean cleaner air but also slightly higher prices at the pump.