A group of determined parents has won its fight to ban alcohol and tobacco advertising on city buses, streetcars and cable cars.

The San Francisco Public Utilities Commission voted unanimously for the restrictions this week, marking a successful end to a campaign started more than two years ago by Parents Opposed to Addictive Drug Advertising."We only have about 50 members, but we went out and sought support from the community and we got it," said Daniel Liebert, the organization's executive director.

The ads bring in $760,000 a year, according to figures by the Municipal Railway, which runs the transit system.

"I know I don't want my government to put a price tag on promoting children to smoke," said Kathleen Moss, the organization's president.

More than 30,000 schoolchildren use city buses to get to school, according to the parents' group.

The Bay Area Rapid Transit District took similar action in 1988. Boston and Seattle have similar bans.

The transit system has a fleet of 1,009 vehicles, according to spokesman Alan Seigel.

He said the new policy will become effective when the line's new advertising contract goes out for bids. The contract begins July 1.