''tert''-Butylhydroquinone (TBHQ, tertiary butylhydroquinone) is a synthetic aromatic organic compound which is a type of phenol. It is a derivative of hydroquinone, substituted with a ''tert''- butyl group.

Applications

Food preservative

In foods, TBHQ is used as a preservative for unsaturated vegetable oils and many edible animal fats. It does not cause discoloration even in the presence of iron, and does not change flavor or odor of the material to which it is added. It can be combined with other preservatives such as

butylated hydroxyanisole Butylated hydroxyanisole (BHA) is a synthetic, waxy, solid petrochemical. Its antioxidant properties have caused it to be widely used as a preservative in food, food packaging, animal feed, cosmetics, pharmaceuticals, rubber, and petroleum produc ...

(BHA). As a

food additive Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives have been used for centuries as part of an effort to preserve food, for example vinegar (pickling), salt (salt ...

, its

E number E numbers ("E" stands for "Europe") are codes for substances used as food additives, including those found naturally in many foods such as vitamin C, for use within the European Union (EU) and European Free Trade Association (EFTA). Commonly ...

is E319. It is added to a wide range of foods. Its primary advantage is extending storage life.''Fats and oils: formulating and processing for applications'', Richard D. O'Brien, page 168

Other

In perfumery, it is used as a fixative to lower the evaporation rate and improve stability. It is used industrially as a stabilizer to inhibit autopolymerization of

organic peroxide In organic chemistry, organic peroxides are organic compounds containing the peroxide functional group (). If the R′ is hydrogen, the compounds are called hydroperoxides, which are discussed in that article. The O−O bond of peroxides easily b ...

s. It is used as an antioxidant in biodiesel. It is also added to

varnish Varnish is a clear transparent hard protective coating or film. It is not a stain. It usually has a yellowish shade from the manufacturing process and materials used, but it may also be pigmented as desired, and is sold commercially in various ...

es,

lacquer Lacquer is a type of hard and usually shiny coating or finish applied to materials such as wood or metal. It is most often made from resin extracted from trees and waxes and has been in use since antiquity. Asian lacquerware, which may be ca ...

s, resins, and oil-field additives.

Safety and regulation

The European Food Safety Authority (EFSA) and the United States Food and Drug Administration (FDA) have evaluated TBHQ and determined that it is safe to consume at the concentration allowed in foods."Opinion of the Scientific Panel on food additives, flavourings, processing aids and materials in contact with food (AFC) on a request from the Commission related to tertiary-Butylhydroquinone (TBHQ)"
European Food Safety Authority, 12 July 2004 The FDA21 C.F.R. § 172.185
/ref> and European Union both set an upper limit of 0.02% (200mg/kg) of the oil or fat content in foods. At very high doses, it has some negative health effects on lab animals, such as producing precursors to stomach tumors and damage to DNA. A number of studies have shown that prolonged exposure to very high doses of TBHQ may be carcinogenic, especially for stomach tumors. Other studies, however, have shown opposite effects including inhibition against

HCA HCA may refer to: Courts * High Court of Australia, the supreme court in the Australian court hierarchy and the final court of appeal in Australia Organizations Europe * Hall–Carpenter Archives, an archive of materials related to gay activism ...

-induced carcinogenesis (by depression of metabolic activation) for TBHQ and other phenolic antioxidants (TBHQ was one of several, and not the most potent). The EFSA considers TBHQ to be noncarcinogenic. A 1986 review of scientific literature concerning the toxicity of TBHQ determined that a wide margin of safety exists between the levels of intake by humans and the doses that produce adverse effects in animal studies. There have been reports of vision disturbances in individuals exposed to this chemical. In addition, TBHQ has been identified by high-throughput screening as having potential immunotoxic effects. Not only that, over time, the chemical can be linked to hyperactivity (worsening the symptoms of ADHD), arthritis, rhinitis, dermatitis, and asthma. It is banned in

Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north ...

, United Kingdom, and other European countries.

References

{{DEFAULTSORT:Butylhydroquinone, Tert- Hydroquinones Food additives Food antioxidants Preservatives Alkylphenols Tert-butyl compounds E-number additives