WASHINGTON — A report released April 7 by the Natural Resources Defense Council calls into question the adequacy of the Food and Drug Administration’s regulatory exemption known as “Generally recognized as safe (GRAS)” that allows companies to determine if an ingredient poses a health risk. The GRAS process allows companies to declare as safe chemicals added to foods without any notification to the F.D.A. or the public, according to the report.

“Americans should expect that their food is safe to eat, but sadly today there’s no guarantee because safety oversight from federal agencies and food manufacturers is shockingly weak and hidden from public scrutiny,” said Tom Neltner, health scientist for the N.R.D.C. and the report’s co-author.  “Congress should close the loophole responsible for this failing now. Until it does, F.D.A. should strictly limit companies’ conflicts of interest and require them to disclose to the agency when they self-approve the safety of a chemical. And consumers should demand that their grocery stores and their favorite brands sell only food with ingredients deemed safe by federal food safety experts.”

The report said information obtained under the federal Freedom of Information Act shows that when the F.D.A. does learn of a chemical proposed to be used in food, the agency often asks questions, but because of the GRAS loophole a company is not bound to answer them and not prohibited from continuing to sell the chemical for use in food. In addition, the N.R.D.C. noted that based on information from notices submitted to the F.D.A., but later withdrawn, companies have sometimes certified their chemicals as safe for use in food despite potentially serious allergic reactions, or adverse reactions in combination with common drugs, or have proposed using amounts of the chemicals in food at much higher levels than company-established safe levels.

Finally, the N.R.D.C. said when companies seek the F.D.A.’s voluntary review of their GRAS determination the agency rejects or triggers withdrawal in one out of every 5 cases.

“At least in some instances, companies may have withdrawn their notices in order to avoid having an F.D.A. rejection made public,” the report said.

“Ensuring the safety of our products — and maintaining the confidence of consumers — is the single most important goal of our industry,” the Grocery Manufacturers Association said in a statement. “Product safety is the foundation of consumer trust, and our industry devotes enormous resources to ensure that our products are safe.

“GRAS determinations are an important part of that framework by helping to ensure the safety of ingredients through rigorous testing and/or analysis of all the relevant data and scientific literature. It is a very thorough and comprehensive process that has, under the current law provided the F.D.A. with authority to challenge the improper marketing of an ingredient as GRAS, and if necessary, act to remove products containing that ingredient from the food supply.”

The N.R.D.C. report cites four ingredients the group said were subject to a withdrawn GRAS notice but have been listed as an ingredient in foods marketed to the public despite F.D.A.’s concerns about their safety. The ingredients in questions include epigallocatechin-3-gallate, gamma-amino butyric acid, sweet lupin protein, fiber and flour, and theobromine.

“The law places responsibility on F.D.A. to ensure food Americans consume is safe,” said Maricel Maffini, co-author of the report. “If the F.D.A. is in the dark about the identity and safety of hundreds of chemicals, it cannot do its job. The “generally recognized as secret” loophole undermines public health.”

On the same day the N.R.D.C.’s report was released, the G.M.A., in conjunction with Michigan State University, announced the creation of the Center for Research on Ingredient Safety. The center is designed to be an independent, academic, science-based center that will serve as an unbiased source for information, research, training and analysis on the safe use of chemical ingredients in consumer packaged goods including foods, beverages, cosmetics and household consumer products.

“Ensuring the safety of our products — and maintaining the confidence of consumers — is the single most important goal of our industry,” said Leon Bruner, chief science officer for the G.M.A. “We are very pleased to be part of the founding of the Center for Research on Ingredient Safety. The center will be an independent resource for a broad range of stakeholders that provides unbiased analysis and information on the safety of ingredients used in foods and consumers products.”

The G.M.A. said the center will be modeled after existing centers of expertise at other academic institutions that focus on allergen and microbiological safety. It will be located at M.S.U. and governed by an advisory board composed of multiple stakeholders, including academic, industry, non-governmental organizations and regulatory representatives.