PEG-200 Hydrogenated Glyceryl Palmate is a chemical, a thickening and co-emulsifying vegetable-based, nitrogen-free component. 

 It is a product structurally related to PEGs (polyethylene glycerol ethers) on the safety of which the scientific literature has conflicting opinions.

• "PEG-200" refers to polyethylene glycol with an average molecular weight of 200. Polyethylene glycol (PEG) is a polyether compound that is used in a variety of applications due to its ability to dissolve in water and many organic solvents.
• "Hydrogenated Glyceryl Palmate" refers to the product of the acid reaction of palm oil and glycerin, followed by hydrogenation. Palm oil acid is a mixture of fatty acids obtained from palm oil and glycerin is a simple compound of polyols. Hydrogenation is a chemical reaction that adds hydrogen to a molecule, resulting in saturation of organic compounds.

Description of raw materials used in production

• Glyceryl Palmate. This is an ester derived from fatty acids present in palm oil and glycerol.
• Ethylene Oxide. Used for pegylating the glyceryl palmate, introducing PEG groups into the molecule.
• Hydrogen. Used in the hydrogenation process.

The synthesis process takes place in several stages:

• Synthesis of Glyceryl Palmate with a treatment known as esterification, which includes the acid reaction of palm oil with glycerin to produce loa Glyceryl Palmate formation.
• Hydrogenation. In this phase the resulting Glyceryl Palmate is hydrogenated by adding hydrogen to the molecule, typically using a catalyst such as nickel. The result is Hydrogenated Glyceryl Palmate.
• Reaction with PEG-200. Hydrogenated Glyceryl Palmate is reacted with PEG-200 through a process known as ethoxylation, which involves the reaction of the compound with ethylene oxide. The result is PEG-200 Hydrogenated Glyceryl Palmate.

Colorless to pale yellow liquid with characteristic odor, soluble in water and in ethanol, isopropanol. acetone, propylene glycol.

It is extracted, by chemical process, from palm, often associated with PEG-7 Glyceryl Cocoate that however has a higher penetration coefficient and is obtained by chemical process, from coconut.

What it is used for and where

Cosmetics

Thickener, co-emulsifier with good compatibility with mucous membranes, skin, used in cosmetics in liquid soaps, shampoos and other cosmetic and body care products (max 8%).

Cleansing agent. Ingredient that cleanses skin without exploiting the surface-active properties that produce a lowering of the surface tension of the stratum corneum. 

Solvent. It is the substance for dissolving or dispersing surfactants, oils, dyes, flavourings, bactericidal preservatives in solution.

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 - Emulsifying agent. Emulsions are thermodynamically unstable and are used to soothe or soften the skin and emulsify, so they need a specific, stabilising ingredient. This ingredient forms a film, lowers the surface tension and makes two immiscible liquids miscible. A very important factor affecting the stability of the emulsion is the amount of the emulsifying agent. Emulsifiers have the property of reducing the oil/water or water/oil interfacial tension, improving the stability of the emulsion and also directly influencing the stability, sensory properties and surface tension of sunscreens by modulating the filmometric performance.

Safety

The Cosmetic Ingredient Review (CIR) Expert Panel, a group that reviews the safety of cosmetic and skin care ingredients in the US, evaluated the scientific data and concluded that PEG-200 Hydrogenated Glyceryl Palmate is safe for use in cosmetics.

Full public report

Synonyms:

• Hydrogenated Glyceryl Palmate
• REWODERM LI 520
• Palmitoyl-rac-glycerol
• Glycerol 1-monopalmitate
• V2999
• 2,3-dihydroxypropyl hexadecanoate
• 1-Monopalmitin
• Palmitin, 1-mono-
• 1-Palmitoylglycerol
• Hexadecanoic acid, 2,3-dihydroxypropyl ester
• Glyceryl palmitate
•  2,3-Dihydroxypropyl palmitate

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A premise on PEGs.

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.