TBHQ

Tertiary Butylhydroquinone or TBHQ, is a form of butane (a gaseous fuel), found in a wide range of foods, that is used to extend a foods shelf life and prevent rancidity.

Commonly Used in:
Chicken Nuggets
Frozen, Packged or Pre-Made processed foods with long shelf life: frozen meals, crackers, chips,cereal bars and fast food

Tertiary Butylhydroquinone or TBHQ, is a form of butane (a gaseous fuel), used to extend the shelf life of food and prevent rancidity; it is in fats, including vegetable oils and animal fats. TBHQ is often used with other additives like BHA, propyl gallate, and butylated hydroxytoluene (BHT). Due to a lack of evidence on the risk of high amounts of TBHQ, the FDA only allows 0.02% of TBHQ oil to be used in food products. Those with high diets of fats, oil and fat emulsions, and frozen fish are likely to exceed the ADI of TBHQ.

If you want to avoid this additive, stay away from processed package foods meant to withstand long shelf lives, and read all food labels carefully searching for:
tert-butylhydroquinone
tertiary butylhydroquinone
TBHQ
butylated hydroxyanisol