California's attorney general disputed the FDA letter Friday, and said it was an attempt to stop a lawsuit the state has filed against tuna companies over the warnings.

"The federal government has no authority to prevent California, or any state, from requiring warnings that provide truthful, important information to consumers," said Tom Dresslar, spokesman for California Attorney General Bill Lockyer.

Labels Can Overexpose Consumers to Warnings?

A year ago, Lockyer sued the nation's three largest canned tuna companies to enforce Proposition 65, California's 1986 law requiring businesses to provide "clear and reasonable" warnings when they expose consumers to known reproductive toxins, such as mercury.

The companies are Tri-Union Seafoods, maker of Chicken of the Sea; Del Monte, maker of Starkist; and Bumble Bee Seafoods, maker of Bumble Bee.

The FDA letter, written by Commissioner Lester Crawford on Aug. 12, argues that the warnings Lockyer is seeking are pre-empted under federal law.

Such warnings "frustrate the carefully considered federal approach to advising consumers of both the benefits and possible risks of eating fish and shellfish," Crawford's letter says.

The letter says the FDA has determined that the best way to warn consumers about health risks is with advisories, targeted to particular audiences, delivered by doctors or specific media outlets. General warning labels can overexpose consumers to warnings, or scare the wrong audience away from food they should be eating, the letter says.

Many People Never See FDA Advisories

Dresslar said many people never see FDA advisories, and providing a posted warning in a supermarket or a label on a can would inform many more people about potential reproductive problems from mercury.

He also contended that the timing of the letter appeared designed to "squash" California's lawsuit. A San Francisco Superior Court trial date is set for Oct. 19, and the defendants have informed California they plan to ask the judge to find that Proposition 65 is pre-empted by federal law, Dresslar said.

"Coincidence? Probably not, considering the Bush administration's propensity to formally side with industry in pre-emption litigation," Dresslar said.

Dr. David Acheson, chief medical officer at the FDA's Center for Food, Safety and Applied Nutrition, said he was not aware of any connection between the letter and the trial timing.

A spokesman for the tuna industry praised Crawford's letter and criticized Lockyer.

"Lockyer dismissed the FDA's concerns without addressing any of the major issues presented," said David Burney, executive director of the US Tuna Foundation. "Tuna should be treated as an important source of nutrition and an important food source for the low-income community, not a political football."