Editing Butylated hydroxytoluene (section)

== Applications ==
BHT is listed by the [[NIH]] Hazardous Substances Data Bank under several categories in catalogues and databases, such as food additive, household product ingredient, industrial additive, personal care product/cosmetic ingredient, pesticide ingredient, plastic/rubber ingredient and medical/veterinary/research.<ref>US Dept of Health & Human Services. Household Products Database. [http://hpd.nlm.nih.gov/] {{Webarchive|url=https://web.archive.org/web/20150905052301/http://hpd.nlm.nih.gov/|date=2015-09-05}}.US EPA. InertFinder. [http://iaspub.epa.gov/apex/pesticides/f?p=175:1:]. US National Library of Medicine. Haz-Map. [http://hazmap.nlm.nih.gov/index.php] {{Webarchive|url=https://web.archive.org/web/20150905065151/http://hazmap.nlm.nih.gov/index.php|date=2015-09-05}}. US National Library of Medicine. Hazardous Substances Data Bank. [http://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?HSDB].</ref>

=== Food additive ===
BHT is primarily used as an antioxidant food additive.<ref>{{Cite web|url=https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=172.115|title=CFR - Code of Federal Regulations Title 21}}</ref> In the United States, it is classified as [[generally recognized as safe]] (GRAS) based on a [[National Cancer Institute]] study from 1979 in rats and mice.<ref name=NTP>[https://ntp.niehs.nih.gov/go/tr150abs Bioassay of Butylated Hydroxytoluene (BHT) for Possible Carcinogenicity], National Cancer Institute, CARCINOGENESIS Technical Report Series No. 150, 1979, 128 pp  [[National Institutes of Health]]{{page needed|date=March 2020}}</ref><ref>{{Cite web |title=Abstract for TR-150 |url=https://ntp.niehs.nih.gov/publications/reports/tr/tr150 |access-date=2025-03-27 |website=National Toxicology Program |language=en}}</ref> It is approved for use in the U.S. by the [[Food and Drug Administration]]: For example, 21 [[Code of Federal Regulations|CFR]] §&nbsp;137.350(a)(4) allows BHT up to 0.0033% by weight in "enriched rice",<ref>{{cite web|url=https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=137.350|title=CFR - Code of Federal Regulations Title 21|website=www.accessdata.fda.gov}}</ref> while 9 CFR §&nbsp;381.147](f)(1) allows up to 0.01% in [[poultry]] "by fat content".<ref>{{Cite web |url=https://www.fda.gov/Food/FoodSafety/RetailFoodProtection/FoodCode/FoodCode2001/ucm092716.htm |title=9 CFR 3, Part 381.147 (Restrictions on the Use of Substances in Poultry Processing) |website=[[Food and Drug Administration]] |access-date=2019-12-16 |archive-url=https://web.archive.org/web/20090709085417/http://www.fda.gov/Food/FoodSafety/RetailFoodProtection/FoodCode/FoodCode2001/ucm092716.htm |archive-date=2009-07-09 }}</ref> It is permitted in the European Union under [[E number|E321]].<ref>{{cite web|title = Scientific Opinion on the re-evaluation of butylated hydroxytoluene BHT (E 321) as a food additive {{!}} European Food Safety Authority|url = http://www.efsa.europa.eu/en/efsajournal/pub/2588|website = www.efsa.europa.eu|access-date = 4 October 2015 |date = 7 March 2012}}</ref>

BHT is used as a preservative ingredient in some foods. With this usage BHT maintains freshness or prevents spoilage; it may be used to decrease the rate at which the texture, color, or flavor of food changes.<ref>{{cite web |url=https://www.fda.gov/food/ingredientspackaginglabeling/foodadditivesingredients/ucm094211.htm#types |title=Food Additives & Ingredients > Overview of Food Ingredients, Additives & Colors |quote=Types of Ingredients: Preservatives[.] What They Do: Prevent food spoilage from [...]; maintain freshness[.] Examples of Uses: Fruit sauces and jellies, beverages, baked goods, cured meats, oils and margarines, cereals, dressings, snack foods, fruits and vegetables[.] Names Found on Product Labels: Ascorbic acid, citric acid, sodium benzoate, calcium propionate, sodium erythorbate, sodium nitrite, calcium sorbate, potassium sorbate, BHA, BHT, EDTA, tocopherols (Vitamin E)[.] |website=www.fda.gov|date=20 February 2020 }}</ref>

Some food companies have voluntarily eliminated BHT from their products or have announced that they were going to phase it out.<ref name=atl>{{cite journal|author=Hamblin, James|title=The Food Babe: Enemy of Chemicals|journal=The Atlantic|date=11 February 2015|url=https://www.theatlantic.com/health/archive/2015/02/the-food-babe-enemy-of-chemicals/385301/|access-date=12 September 2015}}</ref>

=== Antioxidant ===
BHT is also used as an antioxidant in products such as [[metalworking fluids]], [[cosmetics]], [[pharmaceuticals]], [[rubber]], [[transformer oil]]s, and [[embalming]] fluid.<ref name=":0">{{Cite journal |last1=Yehye |first1=Wageeh A. |last2=Rahman |first2=Noorsaadah Abdul |last3=Ariffin |first3=Azhar |last4=Abd Hamid |first4=Sharifah Bee |last5=Alhadi |first5=Abeer A. |last6= Kadir |first6=Farkaad A. |last7=Yaeghoobi |first7=Marzieh |date=2015-08-28 |title=Understanding the chemistry behind the antioxidant activities of butylated hydroxytoluene (BHT): a review |url= https://pubmed.ncbi.nlm.nih.gov/26150290/ |journal=European Journal of Medicinal Chemistry |volume=101 |pages=295–312 |doi=10.1016/j.ejmech.2015.06.026 |issn=1768-3254 |pmid=26150290}}</ref><ref>{{Cite web |last=PubChem |title=Butylated Hydroxytoluene |url=https://pubchem.ncbi.nlm.nih.gov/compound/31404 |access-date=2023-09-01 |website=pubchem.ncbi.nlm.nih.gov |language=en}}</ref> In the [[petroleum industry]], where BHT is known as the [[List of gasoline additives|fuel additive]] [[Antioxidant#Industrial uses|AO-29]] (Innospec), it is used in [[hydraulic fluid]]s, [[turbine]] and [[gear]] oils, and [[jet fuel]]s.<ref name=":0" /><ref>{{Cite book |title=Handbook of preservatives |date=2009 |publisher=Synapse Information Resources |isbn=978-1-890595-66-1 |editor-last=Ash |editor-first=Michael |location=Endicott, NY |page=628 |editor-last2=Ash |editor-first2=Irene}}</ref> BHT is also used to prevent [[Organic peroxide|peroxide]] formation in organic [[ether]]s and other solvents and laboratory chemicals.<ref>{{Cite web|url=https://www.sigmaaldrich.com/chemistry/solvents/learning-center/stabilizer-systems.html|title=Solvents|website = Millipore Sigma}}</ref> It is added to certain [[monomers]] as a [[polymerisation inhibitor]] to facilitate their safe storage.<ref>{{Cite journal |last1=Grohmann |first1=Caio Vinícius Signorelli |last2=Sinhoreti |first2=Mário Alexandre Coelho |last3=Soares |first3=Eveline Freitas |last4=Oliveira |first4=Robson Ferraz de |last5=Souza |first5=Eduardo José de Carvalho |last6=Geraldeli |first6=Saulo |date=24 June 2022 |title=Effect of a polymerization inhibitor on the chemomechanical properties and consistency of experimental resin compo |journal=Brazilian Dental Journal |volume=33 |issue=3 |pages=92–98 |doi=10.1590/0103-6440202204242 |pmid=35766722 |pmc=9645198 }}</ref> Some additive products contain BHT as their primary ingredient, while others contain the chemical merely as a component of their formulation, sometimes alongside [[butylated hydroxyanisole]] (BHA).<ref name="sciam13">{{cite news |title=BHA and BHT: A Case for Fresh? |url=https://www.scientificamerican.com/article/bha-and-bht-a-case-for-fresh/ |publisher=Scientific American |date=19 December 2013}}</ref>

=== Cosmetics ===
The European Union restricts the use of BHT in mouthwash to 0.001% concentration, in toothpaste to 0.01% concentration, and to 0.8% in other cosmetics.<ref>{{cite web |last1=Slavova |first1=Siana |title=New restrictions for Butylated Hydroxytoluene (BHT) and Acid Yellow 3 apply as of July 2023 |url=https://www.obelis.net/news/new-restrictions-bht-acid-yellow-3-cosmetic-products/ |website=Obelis Group |language=en |date=23 June 2023}}</ref>