A consumer group has asked The Food and Drug Administration to ban the food additive BHT, found in a wide variety of products from cake mixes and instant potatoes to shortening and sausages.

The Washington-based Center for Science in the Public Interest (CSPI) has charged that BHT (Butylated-hydroxytoluene) is not only unnecessary but also may be unsafe.

FDA has already shown some concern about the safety of BHT: Last May the preservative was removed from the Generally Recognized As Safe (GRAS) list and placed interim category while further safety testing is conducted.

CSPI calls the agency's decision "half-hearted" because there is already some evidence that the preservative caused lung and ovarian tumors in mice; residues of it collect in human fat and affect the weight and enzyme content of the liver. According to the petition, there is also reason to believe that BHT interacts with steroid hormones and oral contraceptives, the results of which are not yet understood. In addition, BHT causes allergic reactions in some people.

The public interest group's co-director, Dr. Michael Jacobson, said not only are there several alternatives to BHT, but also noted that many food manufacturers have found it unnecessary to use the anti-oxidant to prevent rancidity. Attached to the petition is a list of products - some with BHT, some without. There is BHT in Frito Lay Ruffles potato chips but none in Wise potato chips. Betty Crocker, Giant and Pillsbury yellow cake mixes contain BHT and BHA (a close chemical relative) but Washington yellow cake mix contains neither.

The petition suggests these alternatives to the additive (of which Americans consume a million pounds each year): refigeration, use of dark bottles, citric acid, Vitamin E (another anti-oxidant), vacuum-packing and bottling under inert gas.