Croton oil (Crotonis oleum) is an oil prepared from the seeds of Croton tiglium, a tree belonging to the order Euphorbiales and family Euphorbiaceae, and native or cultivated in India and the Malay Archipelago. Small doses taken internally cause diarrhea. Externally, the oil can cause irritation and swelling. Croton oil is used in some chemical peels, due to its caustic exfoliating effects it has on the skin. Used in conjunction with phenol solutions, it results in an intense reaction which leads to initial skin sloughing. Since croton oil is very irritating and painful, it is used in laboratory animals to study how pain works, pain-relieving and anti-inflammatory drugs, and immunology.
Because croton oil is carcinogenic, it has been used in tumor research. Croton oil is the source of the chemical compound phorbol. Tumor promotion activity was traced to phorbol esters present in croton oil. Pure phorbol 12-myristate 13-acetate which is found in croton oil is now used widely in laboratory research to induce tumor development.
During World War II, the United States Navy added a small amount of croton oil to the neutral grain spirits which powered torpedoes. The oil was intended to prevent sailors from drinking the alcohol fuel. Sailors devised crude stills to separate the alcohol from the croton oil, as alcohol evaporates at a lower temperature than croton oil. Norwegian partisans, ordered by the Quisling government to turn over a catch of sardines to the Nazi German government for shipment to Saint-Nazaire (a U-boat base of operations) arranged with the British for a large shipment of croton oil to flavor the sardines, whose fishy taste was expected to conceal the tampering.
In "The Bulletin" (9 Dowry Square, Hot Wells, May 29, 1845) by the Reverend Richard Harris Barham, a medically inspired poem to relieve the anxiety of a very dear friend, and written a month before Barham's death on June 17, 1845, the attending doctor to his patient advises amongst other treatments for a sore throat that is producing barely a sound: "... Please put out your tongue again!/Now the blister!/Ay, the blister!/ Let your son, or else his sister,/Warm it well, then clap it here, sir,/All across from ear to ear, sir;/That suffices,/When it rises,/Snip it, sir, and then your throat on/Rub a little oil of Croton:/Never mind a little pain!/Please put out your tongue again! ..." The patient was Barham, who had accidentally swallowed a piece of pear core that got into his windpipe on October 28, 1844. Despite the "professional" advice and the very painful and "highest quality" treatments of the time being given freely to him by Doctors Roberts and Scott, and the eminent surgeon Mr. Coulson, for "violent vomiting", "inflamed throat", and then catching "a cold" in April 1845, Barham died.
In popular culture
In John Steinbeck's novel East of Eden, Kate uses it to murder Faye and inherit her whorehouse. Faye is poisoned with a combination of first strychnine (unsuccessfully) and then two drops of croton oil, on a salad of home-canned beans, mimicking accidental botulism poisoning. To allay suspicion, Kate also poisons herself with cáscara sagrada which gives the same cathartic symptoms, but to a non-fatal degree.
In El Dorado starring John Wayne, cayenne pepper, hot mustard, ipecac, asafoetida, croton oil, and gunpowder are the ingredients in an emetic administered to Robert Mitchum's drunken sheriff to sober him up and prevent him from drinking for the foreseeable future. Arthur Hunnicutt's character Bull expresses great surprise that the extract's use will be risked.
- Orra, S; Waltzman, J. T.; Mlynek, K; Duraes, E. F.; Kundu, N; Zins, J. E. (2015). "Periorbital Phenol-Croton Oil Chemical Peel in Conjunction with Blepharoplasty: An Evolving Technique for Periorbital Facial Rejuvenation". Plastic and Reconstructive Surgery 136 (4 Suppl): 99–100. doi:10.1097/01.prs.0000472401.26529.67. PMID 26397611.
- Lawrence Kruger, ed. (2001). Methods in Pain Research. CRC Press.
- Berenblum, I; Shubik, P (1947). "The Role of Croton Oil Applications, Associated with a Single Painting of a Carcinogen, in Tumour Induction of the Mouse's Skin". British Journal of Cancer 1 (4): 379–382. doi:10.1038/bjc.1947.35. PMC 2007538. PMID 18906315.
- Meyer-Bertenrath, JG (1969). "150 Years of croton oil research". Experientia 25 (1): 1–5. doi:10.1007/BF01903855. PMID 4885798.
- E. Hecker (1967-01-31). "Phorbol esters from croton oil: Chemical nature and biological activities". Naturwissenschaften 54 (11): 282–4. Bibcode:1967NW.....54..282H. doi:10.1007/BF00620887. PMID 5589922.
- Ostlund, Mike. Find 'em, chase 'em, sink 'em, Globe Pequot, 2006, p. 88. ISBN 1-59228-862-6
- William B. Breuer (2002). Deceptions of World War II. Wiley & Sons. ISBN 9780471207474.
- Jeffrey D. Schultz; Luchen Li (2005). "East of Eden". Critical Companion to John Steinbeck. Infobase Publishing. p. 68. ISBN 1438108508.
- Steinbeck, John. "21:4". East of Eden.