WASHINGTON – California importer Frank Lettieri is being sued for not warning his customers that his balsamic vinegar contains lead.

True enough, he says. But you would have to drink more than a pint of the vinegar every day to reach the government limit for safe exposure to lead. Most people just sprinkle a few drops onto salads or bread.

Regardless, a voter-passed law in California says consumers have a right to know about lead and other harmful chemicals.

“The ironic part is, it will kill you in California, but it won’t kill you in Nevada,” Lettieri said. “It won’t kill you anywhere else in the country.”

Rather than wrestle with labeling laws that vary from state to state, the food industry wants Congress to prohibit states from requiring food warnings that are tougher than federal law.

In March, the House overwhelmingly approved legislation that would pre-empt state warnings. The Senate held a hearing on the issue in July.

As many as 200 state laws or regulations could be affected, according to the Congressional Budget Office. They include warnings about lead and alcohol in candy, arsenic in bottled water, allergy-causing sulfites and mercury levels in fish.

Opposition is fierce, especially in California, where voters put their right-to-know law on the books 20 years ago. Known as Proposition 65, the law has been used to reduce arsenic in bottled water, mercury in fish and lead in candy and dishes.

Sen. Barbara Boxer, D-Calif., said state warnings can fill critical gaps in federal law. Californians passed Prop 65 “because they wanted to know if dangerous contaminants were in their food and drinking water,” Boxer said at the Senate hearing.