(NaturalNews) Mention Propylene Glycol (PG) to most people and they will probably tell you that it is a toxin. On the other hand, PG comes in more than one formulation, so it needs to be clarified as to which formulation is meant.
The real question is, does it make a difference which one is used, since it is used in everything from hydraulic and brake fluid to snack foods?
The answer is: it does and it doesn't. It is a toxin regardless of which strength is used. Propylene Glycol is a form of mineral oil, an alcohol produced by fermentation of yeast and carbohydrates. This gives it the designation of carbohydrate when used in foods.
Because it comes in several grades, PG has been used for a variety of uses. Industrial grade PG is used as an active ingredient in engine coolants and antifreeze; airplane de-icers; polyurethane cushions; paints, enamels and varnishes; and in many products as a solvent or surfactant. In all fairness, it should be stated that PG was only added to anti-freeze to replace Ethylene Glycol. It had been a problem because dogs often lap up puddles of anti-freeze.
The form most pertinent to this article is the pharmaceutical grade. This is a much less concentrated form of PG and therefore less problematic. That being stated, it is also the controversial form due to its use in products that are either ingested or enter the body through application to the skin. It is commonly used as a solvent in oral, topical and injectable drug products as well as in foods.
Though the controversy over PG wages on, it is not for lack of research. In fact many studies have been conducted, but results have been contradictory. Possibly this is because the concentration of PG in the formulation studied is not always readily apparent. Regardless, the government agencies involved have deemed it safe: The FDA includes Pharmaceutical grade PG on its Generally Recognized As Safe (GRAS) list. The World Health Organization also considers it as safe for use.
Studies on dogs and rats, which were fed doses of PG ranging from two to five grams per kg of body weight per day, showed no links to cancer. The results satisfied the Cosmetic Ingredient Review Expert Panel enough to conclude that there was no carcinogenic risk with low levels of ingestion of PG. A low level of PG was defined, and as a result, the panel recommended that only PG with a concentration less than 50% should be used in cosmetics.
Though cancer might not be a concern, it was also found that PG provoked allergic reactions in patients with eczema and other skin allergies, even in formulations of much less than 50%.
The Material Safety Data Sheet (MSDS) cites skin, liver and kidney damage that can result from contact with PG, and it gives safe handling instructions, calling it a hazardous substance. Though not specified, this is for the more concentrated industrial grade.
On the other hand, studies done in vitro tests on mammalian cells revealed that some cells underwent mutation. Other research conducted twenty and thirty years ago documented toxic effects after repeated small doses of propylene glycol were ingested or repeatedly applied to the skin. Acute toxicity was found to follow I.V. injection of drugs dissolved in significant amounts of PG.
In Europe, where the authorities are much more cautious about what is allowable in cosmetics and foods, propylene glycol is limited to mostly non-food uses. What food uses are allowed are very limited.
The question comes down to more of a quantity issue. In small amounts, used infrequently, propylene glycol may not have negative health effects. If one wants to be on the safe side, though, there are alternatives.
As a beginning, the Natural Health Information Center has suggested products that do not contain PG.
Propylene Glycol-free products and Recommended product for each category:
* Propylene Glycol-free Body washNatural Body Wash by Herbal Choice
More safe products can be found on the Environmental Working Group website, which has a wealth of information on toxins in cosmetics. The site posts a long list of products containing PG along with a safety rating at (http://www.cosmeticsdatabase.com/wordsearch....) . In general, Propylene Glycol was rated as a moderate hazard with a score of four on a scale of one to ten, with one being the least hazardous.
Visitors to the site can also search for products from companies that have signed a safety pledge, and searches can be done for products which do not contain selected ingredients. For example, when PG and parabens were input as ingredients not included in products, over 2000 items came up.
These sites prove that companies can use alternatives to PG. Shane Ellison, a former pharmaceutical chemist and author of Health Myths Exposed said "Working as a chemist, I've seen propylene glycol used with the drugs lorazepam, etomidate, diazepam, nitroglycerin, and phenytoin to increase solubility. It's foreign to the body and as such is toxic. Too much would be about 1800 mg for a 165 lb person.
"The FDA has been pretty honest about the consequences of overdose: metabolic acidosis, lactic acidosis, acute tubular necrosis, allergic contact dermatitis, hemolysis, central nervous system depression, seizures, arrhythmias, and nephrotoxicity.
"The big threat is that it is being used for Over the Counter products... And thus, intake cannot be gauged! Overdose becomes a real and present danger...
"The natural alternative would be 'glycerol' when flavor is not an issue for a supplier."
Glycerol, a byproduct of bio-diesel production, serves as a humectant, a solvent, a filler in commercially prepared low-fat baked goods, a thickening agent in liqueurs, and it may help preserve foods. As a sweetener, it has approximately 27 calories per teaspoon and is 60% as sweet as sucrose, but does not raise blood sugar levels, nor does it feed the bacteria that form plaques and cause dental cavities. The EWG rated it as a two, a very low hazard.
Propylene Glycol has its place. The consumer will need to decide if that place is in his food, medicine and cosmetics. At least, it would seem most healthful to read labels and to limit foods and personal care products which contain PG.
"Final Report of the Safety Assessment of Propylene Glycol and Polypropylene Glycols," Cosmetic Ingredient Review Expert Panel