Butylated hydroxytoluene (AKA BHT)
<p><b >Butylated hydroxytoluene (BHT)</b>, also known as <b >butylhydroxytoluene</b>, is a <a href="http://en.wikipedia.org/wiki/Lipophilic" title="Lipophilic" class="mw-redirect" >lipophilic</a> (fat-soluble) <a href="http://en.wikipedia.org/wiki/Organic_compound" title="Organic compound" >organic compound</a>, chemically a derivative of <a href="http://en.wikipedia.org/wiki/Phenol" title="Phenol" >phenol</a>, that is useful for its <a href="http://en.wikipedia.org/wiki/Antioxidant" title="Antioxidant" >antioxidant</a> properties. European and U.S. regulations allow small percentages to be used as a <a href="http://en.wikipedia.org/wiki/Food_additive" title="Food additive" >food additive</a>, but that is not without controversy as there are claimed links to child <a href="http://en.wikipedia.org/wiki/Hyperactivity" title="Hyperactivity" >hyperactivity</a> as well as to <a href="http://en.wikipedia.org/wiki/Cancer_(disease)" title="Cancer (disease)" class="mw-redirect" >cancer</a>. Conversely, BHT is advocated as a diet supplement and<a href="http://en.wikipedia.org/wiki/Antiviral_drug" title="Antiviral drug" >antiviral</a> useful against <a href="http://en.wikipedia.org/wiki/Herpes" title="Herpes" class="mw-redirect" >herpes</a> family viruses. While there may be some dispute in BHT's use in the human diet, the chemical is widely used in industry wherever oxidation in fluids (e.g. fuel, oil) and other materials must be treated, and <a href="http://en.wikipedia.org/wiki/Free_radical" title="Free radical" class="mw-redirect" >free radicals</a> must be kept in-check.</p>
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Butylated hydroxytoluene is primarily used as an food additive that exploits its antioxidant properties. It is approved for use in European Union under <a href="http://en.wikipedia.org/wiki/E_number" title="E number" >E321</a> and in the U.S. by the <a href="http://en.wikipedia.org/wiki/Food_and_Drug_Administration" title="Food and Drug Administration" >Food and Drug Administration</a> via regulation: For example, 21 <a href="http://en.wikipedia.org/wiki/Code_of_Federal_Regulations" title="Code of Federal Regulations" >CFR</a> <a rel="nofollow" class="external text" href="http://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=137.350" >§137.350</a>(a)(4) allows BHT up to 0.0033% by weight in "enriched rice", while 9 CFR<a rel="nofollow" class="external text" href="http://www.fda.gov/Food/FoodSafety/RetailFoodProtection/FoodCode/FoodCode2001/ucm092716.htm" >§381.147</a>(f)(1) allows up to 0.01% in <a href="http://en.wikipedia.org/wiki/Poultry" title="Poultry" >poultry</a> "by fat content". Brands such as <a rel="nofollow" class="external text" href="http://www.avatarcorp.com/about_us.php" >Avatar Corporation's</a> <b>Avox BHT</b>and <a href="http://en.wikipedia.org/wiki/Eastman_Chemical_Company" title="Eastman Chemical Company" >Eastman Chemical's</a> <b>Tenox BHT</b> are listed for use in foodstuffs like "mixed nuts, margarine, chewing gum" and "enriched rice and frozen breaded shrimp".<sup id="cite_ref-Handbook_3-0" class="reference" ><a href="http://en.wikipedia.org/wiki/Butylated_hydroxytoluene#cite_note-Handbook-3" >[4]</a></sup></p>
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BHT is also documented as an antioxidant additive in such diverse products as <a href="http://en.wikipedia.org/wiki/Cosmetics" title="Cosmetics" >cosmetics</a>, <a href="http://en.wikipedia.org/wiki/Pharmaceuticals" title="Pharmaceuticals" class="mw-redirect" >pharmaceuticals</a>, <a href="http://en.wikipedia.org/wiki/Rubber" title="Rubber" class="mw-redirect" >rubber</a>,<a href="http://en.wikipedia.org/wiki/Transformer_oil" title="Transformer oil" >electrical transformer oil</a> (at 0.35%),<sup id="cite_ref-4" class="reference" ><a href="http://en.wikipedia.org/wiki/Butylated_hydroxytoluene#cite_note-4" >[5]</a></sup> and <a href="http://en.wikipedia.org/wiki/Embalming" title="Embalming" >embalming</a> fluid. In the <a href="http://en.wikipedia.org/wiki/Petroleum_industry" title="Petroleum industry" >petroleum industry</a>, where BHT is known as the<a href="http://en.wikipedia.org/wiki/List_of_gasoline_additives" title="List of gasoline additives" >fuel additive</a> <a href="http://en.wikipedia.org/wiki/Antioxidant#Industrial_uses" title="Antioxidant" >AO-29</a>, and distributed under brands including <a href="http://en.wikipedia.org/wiki/Lanxess#Business_segments" title="Lanxess" >Rhine Chemie</a>'s <b>Additin RC 7110</b> (99.8% pure BHT), it also finds uses in <a href="http://en.wikipedia.org/wiki/Hydraulic_fluid" title="Hydraulic fluid" >hydraulic fluids</a>, <a href="http://en.wikipedia.org/wiki/Turbine" title="Turbine" >turbine</a> and <a href="http://en.wikipedia.org/wiki/Gear" title="Gear" >gear</a> oils, and <a href="http://en.wikipedia.org/wiki/Jet_fuel" title="Jet fuel" >jet fuels</a>,<sup id="cite_ref-Handbook_3-1" class="reference" ><a href="http://en.wikipedia.org/wiki/Butylated_hydroxytoluene#cite_note-Handbook-3" >[4]</a></sup> among other applications.</p>
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Unlike the brands listed above, which contain BHT as their primary ingredient,
many more additive products contain the chemical as a component of their formulation, where it is used alongside (or even replaced by, see below) the lesser-studied <a href="http://en.wikipedia.org/wiki/Butylated_hydroxyanisole" title="Butylated hydroxyanisole" >butylated hydroxyanisole (BHA)</a>.</p>