NEW YORK (AP) - A city proposal to ban restaurants from selling food containing an unhealthy artificial fat could open a new front in a national fight over the safety of America's food supply, legal experts said.
In recent years, states and a few cities interested in ridding kitchens of suspected toxins have become increasingly bold about mandating warning labels for potential hazards such as lead in candy, mercury in fish and pesticides in vegetables.
Some of those measures have prompted fierce opposition from the food industry and members of Congress who say the states are exceeding their authority.
Experts said New York City would take the boldest step yet if its Board of Health approves a proposal to ban restaurants from preparing foods containing more than trace amounts of artificial trans fatty acids.
Under a plan announced last week, chefs at thousands of restaurants would be barred from using partially hydrogenated oil, which has been found in some shortenings and frying oils for decades.
Artificial trans fatty acids are thought to cause cholesterol problems and some studies have blamed them for an epidemic of heart disease deaths.
But federal regulation has been light, and public health law experts said they were stunned that New York would ban a substance the Food and Drug Administration only began listing on food labels this year.
Lawrence O. Gostin, an associate dean at Georgetown University's law school and director of the Center for Law and the Public's Health, called the proposal "breathtaking."
He said it was sure to prompt a lawsuit challenging the city's authority to enact such a measure. Big fast food companies that use artificial trans fats to prepare french fries, muffins and doughnuts might also sue over the potential impact of the rules on interstate commerce, he said.
"Certainly if there is a local deli in New York that is regulated by the local health department, it is clearly for the city to decide what is safe and what isn't," Gostin said, "But if you're talking about large chains like McDonald's or Burger King ... then there are powerful questions of federalism at stake.
"On the other hand," he added, "when the federal government refuses to act or neglects to act in the face of a major health crisis, then sometimes you need cities and states to step in to the vacuum and protect the public."
Anthony M. DiLeo, a professor of health care law at Tulane Law School who also teaches at Tulane Medical School, said public health agencies have a well-established right to ban items that are inherently dangerous, like spoiled food or lead in paint.
But the limits of a city's authority when it comes to something like trans fat are less clear, he said.
"You get to something here that is not a bacteria, it is not a virus, it is not an immediate danger ... One meal containing a trans fat is not dangerous, per se," DiLeo said. "If you have the authority to ban that, you would have to assume you have the authority to ban all sorts of things that, in small amounts, can't be harmful, but in large amounts could be."