Chicago ? Antibiotic-free foods are not necessarily safer, according to an Institute of Food Technologists study to be released Monday.

The study, conducted by a panel of food scientists and microbiologists, aims for the heart of the marketing campaigns in the past decade by organic food advocates who have suggested there is an overuse of antibiotics and that antibiotic-free foods are better for human consumption.

One such group is the Organic Trade Assn., based in Greenfield, Mass., which represents many of the nation’s organic food producers. The association cites 10 studies from 2000 and 2001 of antibiotic use in farming to support its stand that antibiotics have been abused by American farmers.

“What we are trying to do is bring a balance to the discussion,” said Michael Doyle, chairman of the panel assembled by the Chicago-based Institute of Food Technologists and a professor and director of the Center for Food Safety at the University of Georgia. “The study does raise questions about those groups using this as a basis for their promotion of organic and natural products.”

Doyle and the Institute of Food Technologists say they don’t dismiss concerns about overuse of antibiotics or antimicrobials. However, they do warn against reducing the levels of antibiotic use in food production, saying eliminating those drugs may have little effect on bacteria that might develop resistance to antibiotic treatment.