Restaurant Meats Higher In Suspected Carcinogens

Suspected cancer-causing compounds known as heterocyclic amines, often formed during cooking, were found in restaurant-prepared meats at levels as much as ten times higher than similar fast food items previously analyzed by the scientists. The study involved beef hamburgers, steaks and pork ribs, purchased from three different national restaurant chains in the Beltsville, Md., area near Washington, D.C.

The study from Lawrence Livermore National Laboratory, the National Cancer Institute and the U.S. Department of Agriculture is reported in the Oct. 31 Web edition of the Journal of Agricultural and Food Chemistry, published by the American Chemical Society, the world's largest scientific society. It is scheduled to appear in the November 16 print edition of the peer-reviewed journal.

Heterocyclic amines are known carcinogens in animals and are believed to contribute to cancer in people.

"Time and temperature" probably account for the difference in fast food and that from other types of restaurants, says Livermore chemist Mark Knize, lead author for the report. Although fast food chains would not divulge their preparation secrets, he said, the researchers believe that fast food cooking times and temperatures are quicker and lower than other restaurants. Previous research has demonstrated that hotter temperatures and longer cooking times are important to the formation of heterocyclic amines.

This is the first time that measurements have been made of heterocyclic amines in meats specifically prepared by restaurant chefs, according to Knize. The "field test" is significant, he says, since it gives clear support to what previously had only been laboratory studies of the formation of the compounds. There are no established rules or guidelines for the acceptable level of heterocyclic amines in food, says Knize.