RIALTO - Hundreds of residents and representatives of organizations around the state came to a rowdy forum Wednesday night to demand that an ingredient used to produce rocket fuel, perchlorate, be cleaned out of the local drinking water supply.

The event, held by the Center for Community Action and Environmental Justice, featured marching, Aztec dancers, a hearing before a panel of guest activists and calls for action.

"This particular pollutant is really worrisome," said UC San Francisco medical professor Gina Solomon during a presentation on the health effects of perchlorate.

Well-known activist Dolores Huerta was expected to lead a panel of guests to demand change, but she was unable to make it to the event.

Perchlorate is used to produce different types of explosives, and although its health effects are not well understood, it can interfere with the thyroid gland.

A number of residents took the opportunity to tell the panel - which later voted to have the State Water Resources Control Board order cleanup - about the problem.

The center's executive director, Penny Newman, highlighted how much longer it has taken to clean up the perchlorate in Rialto than it took to clean up perchlorate discovered in Redlands the same year.

Rialto has accused dozens of parties of being responsible for the pollution, while only one party caused the contamination in Redlands.

But Newman said Redlands is a wealthier and predominately white community with more political influence than Rialto.

"I don't know too many people who say race does not play a role in our society today," she said before the event.

The contamination has been spreading from Rialto's north end through the city and into Colton. Local water companies have spent millions of dollars to clean it out of the water they serve their customers.

The entire mess could cost $300 million to clean up.

Rialto and Colton have tried a number of strategies to get the dozens of suspected polluters, which include Goodrich, Black and Decker and Pyro Spectaculars, to clean it up.

A federal lawsuit is still in the early stages, and the state regulatory bodies charged with monitoring water quality have struggled to move the case forward.

State hearings have been delayed numerous times, most recently from July to late August, delays Newman called "unacceptable."

Contact writer Jason Pesick at (909) 386-3861 or via e-mail at jason.pesick@sbsun.com.