|Preferred IUPAC name
2-tert-Butyl-4-methoxyphenol and 3-tert-butyl-4-methoxyphenol (mixture)
3D model (JSmol)
|E number||E320 (antioxidants, ...)|
CompTox Dashboard (EPA)
|Molar mass||180.247 g/mol|
|Density||1.0587 g/cm3 at 20 °C|
|Melting point||48 to 55 °C (118 to 131 °F; 321 to 328 K)|
|Boiling point||264 to 270 °C (507 to 518 °F; 537 to 543 K)|
|Insoluble in water|
|Solubility||Freely soluble in ethanol, methanol, propylene glycol; soluble in fats and oils|
Refractive index (nD)
|1.5303 at 589.3 nm|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
what is ?)(
Butylated hydroxyanisole (BHA) is an antioxidant consisting of a mixture of two isomeric organic compounds, 2-tert-butyl-4-hydroxyanisole and 3-tert-butyl-4-hydroxyanisole. It is prepared from 4-methoxyphenol and isobutylene. It is a waxy solid used as a food additive with the E number E320. The primary use for BHA is as an antioxidant and preservative in food, food packaging, animal feed, cosmetics, rubber, and petroleum products. BHA also is commonly used in medicines, such as cholecalciferol (Vitamin D3), isotretinoin, lovastatin, and simvastatin, among others.
Since 1947, BHA has been added to edible fats and fat-containing foods for its antioxidant properties as it prevents rancidification of food which creates objectionable odors. Like butylated hydroxytoluene (BHT), the conjugated aromatic ring of BHA is able to stabilize free radicals, sequestering them. By acting as free radical scavengers, further free radical reactions are prevented.
The U.S. National Institutes of Health report that BHA is reasonably anticipated to be a human carcinogen based on evidence of carcinogenicity in experimental animals. In particular, when administered in high doses as part of their diet, BHA causes papillomas and squamous cell carcinomas of the forestomach in rats and Syrian golden hamsters. In mice, there is no carcinogenic effect; in fact, there is evidence of a protective effect against the carcinogenicity of other chemicals.
When examining human population statistics, the usual low intake levels of BHA show no significant association with an increased risk of cancer. The state of California has, however, listed BHA as a carcinogen.
The European Commission has conducted an evaluation of literature. They noted the lack of potential for the compound to induce carcinogenic effects in humans; studies showing carcinogenic effects in hamsters are not relevant to humans (which lack a forestomach). Also noted is that endocrine disruption, if any, is only likely to be present at levels vastly exceeding the intake as a food. 
The International Agency for Research on Cancer (IARC) - Summaries & Evaluations stated Butylated hydroxyanisole was tested for carcinogenicity in two experiments in rats and in two experiments in hamsters by administration in the diet, inducing benign and malignant tumours of the forestomach. 
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