PEG-75 Shea Butter Glycerides is a chemical compound, alkyl glyceride, a mixture derived from PEG (PEG stands for Polyethylene glycol) from shea butter oil mono- and diglycerides. The number appearing after the abbreviation PEG refers to mol of ethylene oxide and the higher this number is, the less it can penetrate the skin.
It appears in the form of a waxy liquid or clear wax.
Since the PEG (Polyethylene glycol) family is very numerous and can be found in cosmetic, industrial, pharmaceutical, medical and other products, it is necessary to make an introductory statement on the subject, which is rather complex from a safety point of view because these products not only come into contact with the skin, but, as in the case of medical products, are ingested.
PEGs (polyethylene glycol) polymerise condensed ethylene oxide and water and are referred to as polyethylene glycols, but in reality they are complex chemical components, polymers bonded together. For example, plastic is polyethylene and has a hard consistency, while polyethylene combined with glycol forms a liquid. PEGylation is produced not only as etherification, but also as transesterification, which is the transformation of an alcohol by an ester. The number appearing after the abbreviation PEG refers to mol of ethylene oxide and the higher this number is, the less it can penetrate the skin.
Safety. The term 'eth' refers to the ethoxylation process (reaction with ethylene oxide) after which residues of ethylene oxide and 1,4-dioxane, chemical compounds considered carcinogenic, may remain in the final product. It depends on the degree of purity resulting from the completed reaction.
What it is used for and where
Cosmetics
Average of polyethylene glycol: 75 mole of ethylene oxide.
Skin conditioning agent - Emollient. Emollients have the characteristic of enhancing the skin barrier through a source of exogenous lipids that adhere to the skin, improving barrier properties by filling gaps in intercorneocyte clusters to improve hydration while protecting against inflammation. In practice, they have the ability to create a barrier that prevents transepidermal water loss. Emollients are described as degreasing or refreshing additives that improve the lipid content of the upper layers of the skin by preventing degreasing and drying of the skin. The problem with emollients is that many have a strong lipophilic character and are identified as occlusive ingredients; they are oily and fatty materials that remain on the skin surface and reduce transepidermal water loss. In cosmetics, emollients and moisturisers are often considered synonymous with humectants and occlusives.
Surfactant - Cleansing agent. Cosmetic products used to cleanse the skin utilise the surface-active action that produces a lowering of the surface tension of the stratum corneum, facilitating the removal of dirt and impurities.
Surfactant - Solubilising agent. Solubilisation facilitates the diffusion and transport of many cosmetic ingredients, even in the form of microemulsions, on the stratum corneum, improving the effectiveness of formulations.
PEG-75 Shea Butter Glycerides is used in cosmetic products as a surfactant, solubilizing agent. It contains stearic and oleic, linoleic and palmitic fatty acids. It also contains vitamins A, F, E that improve circulation and growth, on the epidermis, of cells.
In the composition of shea butter, the triglycerides contained in the fatty portion of the shea act as a conditioning agent and nourish the skin, while the wax portion of the shea, which acts as a conditioner, has the function of locking in moisture. The overall action of shea butter softens the skin.
On the hair it has a softening action, locks in moisture and tends to prevent brittleness of the hair.
Shea butter is considered as one of the best anti-aging and moisturizing agents for the skin.
It also offers mild UV protection (up to SPF ~6).
Studies
Experts at CIR (Cosmetic Ingredients Review) found no contact problems, but recommend avoiding use on injured skin (1).
For PEG-75, the inhalation toxicity report at a concentration above 1008 mg/m3 caused slight or no toxicity in laboratory animals (2).
References_____________________________________________________________
(1) Johnson W Jr; Cosmetic Ingredient Review Expert Panel. Final report on the safety assessment of PEG-25 propylene glycol stearate, PEG-75 propylene glycol stearate, PEG-120 propylene glycol stearate, PEG-10 propylene glycol, PEG-8 propylene glycol cocoate, and PEG-55 propylene glycol oleate. Int J Toxicol. 2001;20 Suppl 4:13-26. doi: 10.1080/10915810152902556.
(2) Concentration of Use by FDA Product Category: PEG Propylene Glycol Esters - Beth A. Lange, Ph.D. - Industry Liaison to the CIR Expert Panel - February 16, 2016
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And a premise on PEG.
Since the PEG (1) family is numerous and is found in many cosmetic, cleaning and medicinal products and others, we need a cognitive premise on the subject that is rather complex from the point of view of safety because these products not only come into contact with the skin but, as in the case of medicine, they are also ingested.
PEG or polyethylene glycols polymerise the condensed ethylene oxide and water and are called polyethylene glycols, but in reality, they are complex chemical components, polymers bound together. For example, plastic is polyethylene and has a hard consistency, while polyethylene aggregated to the glycol forms a liquid.
The number that appears after the initials PEG represents the molecular weight and the higher this number is, the less it penetrates the skin.
Here below are some studies in Medicine that refer to the use of PEG Polyethylene glycol in various fields.
Intestine
Polyethylene glycol with or without electrolytes is effective for the treatment of functional constipation, both in adults and in paediatric patients, with great safety and tolerability. These preparations are the most effective osmotic laxatives (more than lactulose) and are the first-line treatment for functional constipation in the short- and long-term. They are as effective as enemas in faecalomas, avoid the need for hospitalisation and are well tolerated by patients (especially when given without electrolytes) (2).
In the preparation for colonoscopy, polyethylene glycol tablets confirmed efficacy, acceptability, tolerance and safety similar to those of sodium phosphate (3).
For peripheral nerve repair (4).
Eyes
Dry eye syndrome is a disorder that affects 5-34% of the world's adult population with reduced quality of life. Artificial or lubricating tears are the most used therapy for treating this condition due to their low side effects profile, which attempt to modify the properties of the tear film. Polyethylene glycol has demonstrated clinical efficacy in the treatment of this condition (5).
Brain
Polyethylene glycol facilitates the neuroprotective effects of magnesium in head injuries (6).
Tumors
For transarterial chemoembolization, Polyethylene glycol is effective and safe for the treatment of liver cancer, as indicated by good tolerability, quality of life and high tumour response (7).
Cosmetics
Many types of PEG are hydrophilic and are used as creams, topical dermatological preparations and in cosmetic products such as surfactants, emulsifiers, detergents, humectants and skin conditioners.
Safety varies from type to type given the structural complexity (8).
References___________________________________________________________________
(1) Fruijtier-Pölloth C. Safety assessment on polyethylene glycols (PEGs) and their derivatives as used in cosmetic products. Toxicology. 2005 Oct 15;214(1-2):1-38. doi: 10.1016/j.tox.2005.06.001.
(2) Mínguez M, López Higueras A, Júdez J. Use of polyethylene glycol in functional constipation and fecal impaction. Rev Esp Enferm Dig. 2016 Dec;108(12):790-806. doi: 10.17235/reed.2016.4571/2016.
Santos-Jasso KA, Arredondo-García JL, Maza-Vallejos J, Lezama-Del Valle P. Effectiveness of senna vs polyethylene glycol as laxative therapy in children with constipation related to anorectal malformation. J Pediatr Surg. 2017 Jan;52(1):84-88. doi: 10.1016/j.jpedsurg.2016.10.021.
(3) Chaussade S, Schmöcker C, Toulemonde P, Muñoz-Navas M, O'Mahony V, Henri F. Phosphate tablets or polyethylene glycol for preparation to colonoscopy? A multicentre non-inferiority randomized controlled trial. Surg Endosc. 2017 May;31(5):2166-2173. doi: 10.1007/s00464-016-5214-1.
Tsunoda T, Sogo T, Iwasawa K, Umetsu S, Oikawa-Kawamoto M, Inui A, Fujisawa T. Feasibility and safety of bowel cleansing using low-volume polyethylene glycol with ascorbic acid before pediatric colonoscopy: A pilot study. Dig Endosc. 2017 Mar;29(2):160-167. doi: 10.1111/den.12756.
(4) Hoffman AN, Bamba R, Pollins AC, Thayer WP. Analysis of polyethylene glycol (PEG) fusion in cultured neuroblastoma cells via flow cytometry: Techniques & optimization. J Clin Neurosci. 2017 Feb;36:125-128. doi: 10.1016/j.jocn.2016.10.032.
(5) Pérez-Balbuena AL, Ochoa-Tabares JC, Belalcazar-Rey S, Urzúa-Salinas C, Saucedo-Rodríguez LR, Velasco-Ramos R, Suárez-Sánchez RG, Rodríguez-Carrizalez AD, Oregón-Miranda AA. Efficacy of a fixed combination of 0.09 % xanthan gum/0.1 % chondroitin sulfate preservative free vs polyethylene glycol/propylene glycol in subjects with dry eye disease: a multicenter randomized controlled trial. BMC Ophthalmol. 2016 Sep 20;16(1):164. doi: 10.1186/s12886-016-0343-9.
Labetoulle M, Messmer EM, Pisella PJ, Ogundele A, Baudouin C. Safety and efficacy of a hydroxypropyl guar/polyethylene glycol/propylene glycol-based lubricant eye-drop in patients with dry eye. Br J Ophthalmol. 2017 Apr;101(4):487-492. doi: 10.1136/bjophthalmol-2016-308608.
(6) Busingye DS, Turner RJ, Vink R. Combined Magnesium/Polyethylene Glycol Facilitates the Neuroprotective Effects of Magnesium in Traumatic Brain Injury at a Reduced Magnesium Dose. CNS Neurosci Ther. 2016 Oct;22(10):854-9. doi: 10.1111/cns.12591.
(7) Aliberti C, Carandina R, Sarti D, Mulazzani L, Catalano V, Felicioli A, Coschiera P, Fiorentini G. Hepatic Arterial Infusion of Polyethylene Glycol Drug-eluting Beads for Primary and Metastatic Liver Cancer Therapy. Anticancer Res. 2016 Jul;36(7):3515-21.
(8) Jang HJ, Shin CY, Kim KB. Safety Evaluation of Polyethylene Glycol (PEG) Compounds for Cosmetic Use. Toxicol Res. 2015 Jun;31(2):105-36. doi: 10.5487/TR.2015.31.2.105.
PEG-75 Shea Butter Glycerides 
