WASHINGTON – With a bowl of lead-contaminated Mexican candy on the table between them, California's senators vowed this morning to do all they can to prevent a bill that would require national rules for food safety from passing.

The National Uniformity for Food Act, said Sens. Barbara Boxer and Dianne Feinstein, both Democrats, would gut the food safety protections included in California's Proposition 65, passed 20 years ago,

The bill, authored by Sen. Richard Burr, R-N.C., would ban states from setting requirements or posting warnings on foods that differed from federal rules.

"This bill is a major assault on California's initiative," Feinstein said at a Health, Education, Labor and Pensions committee hearing. "On behalf of my colleague Senator Boxer and I, if this bill were to come to the floor, we would use every parliamentary device available to us to stop it."

Proposition 65 requires warning labels on products containing chemicals known to cause cancer or harm the reproductive system.

Supporters say that measure over the years has help protect state residents. Opponents – most notably the food industry – say it has led to frivolous lawsuits.

"The bill before us seeks consistency in substantive standards between state and federal requirements," said panel chairman Sen. Mike Enzi, "Do consumers really benefit from a 50-state hodgepodge of different warnings and labels on these products?"

The federal food-safety bill has passed the House. Enzi, R-Wyo., hopes to get a bill to the floor by the end of this year.

Feinstein and Boxer – backed up by a letter signed by 37 state attorneys general who oppose the measure – said that the federal government is not equipped to do the food-safety regulation that has always been done by the states. Gov. Arnold Schwarzenegger also opposes the bill, they said.

"This is candy with lead in it, dangerous lead," Boxer said pointing to the lollipops and other treats in the bowl on the witness table. "This is a photograph of lead-tainted candy being given to little children," she added, referring to a blow-up of a picture that appeared as part of The Orange County Register's series last year on lead in candy.

"In our state, we have blocked this, and the federal government has no such law," Boxer said.

Three of the four other witnesses supported the bill. They included the manufacturer of Wheatina, a hot cereal, who says he is being sued by a California lawyer because his product contains acrylamide, a substance recently discovered to possibly cause cancer.

Food-safety agencies around the world have been studying acrylamide, said William Stadtlander, who produces Wheatina, "and none of them have found any significant health risk or recommended any acrylamide warnings."

Peter Hutt, a former Food and Drug Administration lawyer, said California's law has led to unnecessary litigation.

But William Hubbard, who recently retired from the FDA, insisted that the bill "is a solution in search of a problem" and that food safety should be left to the states.