Target's move follows announcements by several supermarket chains, including Safeway Inc. and Ahold NV's Giant Food and Stop & Shop stores, and meat and poultry processor Tyson Foods Inc., the nation's largest, that they would stop selling meat treated with carbon monoxide, a gas deemed safe by the Food and Drug Administration. It also follows congressional inquiries into the safety of a wide range of food products.

This year, big companies received letters from House Energy and Commerce Chairman John Dingell and committee member Bart Stupak, both Michigan Democrats who have led congressional opposition to the use of carbon monoxide on meat.

"We all rely heavily on the color of meat to determine its freshness," Rep. Dingell said last month when Giant announced its plan to stop selling treated meat. "Spiking meat with carbon monoxide can deceive consumers into thinking meat is fresher than it truly is."

Target, which sells packaged meat in 210 of its 1,537 stores, sent a letter Friday to the Agriculture Department seeking permission to add a warning to meat labels. The proposed label states: "CONSUMER NOTICE: Carbon monoxide has been used to preserve the color of this product. Do not rely on color or the 'use or freeze by' date alone to judge the freshness of the product. For best results please follow the Safe Handling Instructions." That language is similar to disclosure wording in bills introduced by Messrs. Dingell and Stupak.

"Target places the highest priority on consistently offering safe, high-quality products for our guests," said Amy von Walter, a Target spokeswoman. "All of the meat we sell meets or exceeds Food and Drug Administration and United States Department of Agriculture guidelines."

The developments came as Mr. Stupak's subcommittee on investigations prepared for a hearing today at which lawmakers are expected to press Bush-administration and food-industry officials on the use of carbon monoxide. The hearing is part of a series initiated by Mr. Dingell and fellow Democrats on the nation's food-safety system and how the administration and the industry have responded to recent incidents of tainted food involving a range of items from spinach to seafood to pet food.

Amanda Eamich, a spokeswoman for the Agriculture Department's Food Safety and Inspection Service, said the agency will consider Target's request. Department officials will testify today.

The FDA allows the use of carbon monoxide on meat, poultry and seafood, putting it in a category called Generally Recognized As Safe. Regulators elsewhere are more strict; the European Union, for example, doesn't allow companies to use carbon monoxide to treat meat.

The meat industry has generally supported the use of carbon monoxide, saying it is limited and poses no public-health risk.

Consumer advocates and some Democrats on Capitol Hill have argued against the practice.

"We have questions regarding Target's decision to sell prepackaged fresh meats that have apparently been deceptively colored, and the conditions under which these products are sold," Messrs. Dingell and Stupak wrote in their letter to Target in September.