Food allergies
TBHQ causes T cells to release a set of proteins that may trigger allergies to such foods as nuts, milk, eggs, wheat and shellfish.

EAST LANSING, MICH. — A professor at Michigan State University has received a five-year grant to support her research on a possible link between the food additive tertiary butylhydroquinone (TBHQ) and a rise in food allergies.

The National Institute of Environmental Health Sciences has awarded Cheryl Rockwell, an assistant professor of pharmacology and toxicology in the College of Human Medicine at Michigan State University in East Lansing, with “The Outstanding New Environmental Scientist” award, which comes with a $1.5 million, five-year grant.

Her research began nine years ago and shows TBHQ causes T cells, which are part of the body’s immune system, to release a set of proteins that may trigger allergies to such foods as nuts, milk, eggs, wheat and shellfish.

Cheryl Rockwell, Michigan State University
Cheryl Rockwell is an assistant professor of pharmacology and toxicology in the College of Human Medicine at Michigan State University.

“I think of the immune system as a military force,” Dr. Rockwell said. “Its job is to protect the body from pathogens, such as viruses. The T cells are the generals.”

T cells normally release proteins known as cytokines that help to fight invaders. When TBHQ was introduced into laboratory models, however, the T cells released a different set of cytokines that are known to trigger allergies in some foods.

“The T cells stopped acting as soldiers in the defense against pathogens and started causing allergies,” she said. “What we’re trying to find out now is why the T cells are behaving this way.”

TBHQ acts as a preservative in such foods as cooking oils, nuts, crackers, waffles and bread, according to Michigan State University.

TBHQ
TBHQ acts as a preservative in such foods as cooking oils, nuts, crackers, waffles and bread.

TBHQ is an approved antioxidant for fats and oils, according to the fourth edition of Baking Science & Technology published by Sosland Publishing Co., Kansas City. It is heat stable at normal baking and frying temperatures, which means TBHQ may stabilize the fat in the final food product.

TBHQ may be found in baking ingredients, such as serving as a preservative for fats and oils, said Brian Strouts, vice-president, baking and food technical services at AIB International, Manhattan, Kas.

Brian Strouts, AIB International
Brian Strouts, vice-president of baking and food technical services at AIB International

“You may find it in something like shortening or margarines, or even some liquid oils,” he said. “You might even find it in some things that are high fat, like decoration materials for cake.”

TBHQ thus generally is not added by itself at the bakery but is added to ingredients that then are added to the final food product at the bakery.

Dr. Rockwell said TBHQ often is not listed on the ingredient list of a product.

Margarine, TBHQ
TBHQ may be found in shortening or margarines.

Mr. Strouts said a gray area exists on whether TBHQ should appear on the ingredient list. If it is a component of an ingredient, such as margarine or chocolate, it may need to be added parenthetically, or in parentheses right after the ingredient.

“If you decide it’s not functional as a preservative in the finished product, then you don’t have to label for it,” he said. “It seems to be a company-by-company decision.”

Companies wanting to switch to clean labels or simple ingredient lists may be avoiding TBHQ.

“It’s been my impression in general that that is one of the antioxidants that a lot of people are moving away from,” Mr. Strouts said.