TBHQ Side Effects

TBHQ is the acronym used to describe tertiary butylhydroquinone, which is an antioxidant that comes from petroleum and is related to butane. It is often used as a preservative, applied for example to fast-food items or directly onto food. It appears in many high-fat prepackaged and processed food items. Like many chemicals, if taken in great excess, it can be toxic. Although more research needs to be done, side effects have not thus far been clinically demonstrated in the quantities that people usually eat.

Usage

TBHQ reduces "oxidative deterioration" in foods it is applied to -- in other words, it acts as preservative by delaying the onset of rancidness. It also therefore extends shelf life of processed foods.

Toxicity

As a food additive, the FDA allows TBHQ to make up no more than 0.02 percent of the total oils in a food. Consuming up to a gram of TBHQ can cause variable toxicity, and up to 5 grams can be fatal. For perspective, it would take 312.5 McDonald's chicken nuggets (if they contain a full 0.02% of TBHQ) to consume a single gram.

Side Effects

Consuming high doses of TBHQ -- between 1 and 4 grams, approximately -- can lead to a variety of negative symptoms, including nausea, vomiting, ringing in the ears, delirium and collapse. But the sheer amount of food consumption necessary to be afflicted by TBHQ toxicity generally makes these symptoms extremely rare.

Carcinogenesis

In toxicity studies, long-term, high-dose TBHQ administration in lab animals showed a tendency for them to develop cancerous precursors in the stomach, as well as causing DNA damage. But unlike other antioxidant additives, it did not cause lung lesions in laboratory animals.

TBHQ in Children

There has been some anecdotal evidence that TBHQ can cause anxiety, restlessness, and aggravation of ADHD symptoms, although there have been no clinical studies that show any link between food additives and behavioral disorders in children.