Is propylene glycol harmful for your skin?
Posted 26 March 2010 - 07:11 PM
Propylene glycol is Commonly found in:
Posted 26 March 2010 - 11:02 PM
I was researching this just yesterday, wow! Anyhow, this is what I found:
On Skindeep's Cosmetic Database:
On the CDC website
What is scary is that we don't know the amounts used in personal care items and cosmetics, since they're not regulated items.
And according to goldenbutterfly.net:
| Propylene Glycol (PG): Propylene Glycol serves as a Humectant - a substance that helps to retain moisture content. It is also a wetting agent and solvent, so it is used by many cosmetic manufacturers to facilitate the process of dissolving and combining ingredients. Propylene Glycol is widely used in skin cream, and many other personal care products. Propylene Glycol is also one of the key ingredients in embalming fluid, anti-freeze, brake fluid, hydraulic fluid, de-icer, paints and floor wax. The Material Safety Data Sheet (MSDS) for Propylene Glycol clearly states: "Implicated in contact dermatitis, kidney damage and liver abnormalities; Can inhibit skin cell growth in human tests, and can damage cell membranes causing rashes, dry skin and surface damage." The MSDS also cautions: Acute Effects: "May be harmful by inhalation, ingestion or skin absorption. May cause eye irritation, skin irritation. Exposure can cause Gastrointestinal disturbances, Nausea, Headache, Vomiting and Central Nervous System depression." Propylene Glycol is toxic, and it will actually retards your skin's ability to maintain normal cellular regeneration. |
In 1992, the FDA proposed a ban on Propylene Glycol in louse-killing products because it has not been shown to be safe and effective for its stated claims, yet, Propylene Glycol is allowed to be used in cosmetics in concentrations up to 50%. Animals who were experimentally exposed (not by us) to Propylene Glycol suffered all of the above symptoms, including mild to profound central nervous system depression as well as heart arrhythmia, respiratory failure, narcosis (profound stupor), growth depression, decreased blood pressure, and even death. The recommended method of storage for undiluted propylene glycol is in an explosion-proof refrigerator.
Posted 26 March 2010 - 11:24 PM
This is very creepy but I wonder how true this is.
Posted 27 March 2010 - 02:12 AM
When in doubt, look at the ingredients' list on your product, the INCI listing. It should give you an idea of the proportions.
Also, here's a part of Wikipedia's article on propylene glycol :
| Propylene glycol is metabolized in the human body into pyruvic acid, which is a normal part of the glucose metabolism process and is readily converted to energy. |
The oral toxicity of propylene glycol is very low, and large quantities are required to cause perceptible health damage in humans. Serious toxicity will occur only at plasma concentrations over 4g/L, which requires extremely high intake over a relatively short period of time. It would be nearly impossible to reach toxic levels by consuming foods or supplements, which contain at most 1g/kg of PG. Cases of propylene glycol poisoning are related to either inappropriate intravenous use or accidental ingestion of large quantities by children.
The potential for long-term toxicity is also low. In one study, rats were provided with feed containing as much as 5% PG over a period of 104 weeks and they showed no apparent ill effects. Because of its low chronic oral toxicity, propylene glycol was classified by the U. S. Food and Drug Administration as "generally recognized as safe" (GRAS) for use as a direct food additive.
Prolonged contact with propylene glycol is essentially non-irritating to the skin. Undiluted propylene glycol is minimally irritating to the eye, and can produce slight transient conjunctivitis (the eye recovers after the exposure is removed). Exposure to mists may cause eye irritation, as well as upper respiratory tract irritation. Inhalation of the propylene glycol vapors appears to present no significant hazard in ordinary applications. However, limited human experience indicates that inhalation of propylene glycol mists could be irritating to some individuals. Therefore inhalation exposure to mists of these materials should be avoided. Some research has suggested that propylene glycol not be used in applications where inhalation exposure or human eye contact with the spray mists of these materials is likely, such as fogs for theatrical productions or antifreeze solutions for emergency eye wash stations.
Propylene glycol does not cause sensitization and it shows no evidence of being a carcinogen or of being genotoxic.
There is limited evidence that intravenous injection of propylene glycol can cause adverse responses in a small number of people. A Clinical Journal of Medicine article describes two cases of adult men experiencing psychosis from use of injected phenytoin that contained PG as a solvent. Their symptoms resolved when they were switched to a phenytoin formulation without propylene glycol.
Posted 27 March 2010 - 06:02 AM
Propylene glycol (along with other glycols and glycerol) is a humectant or humidifying and delivery ingredient used in cosmetics. You can find Web sites and spam emails stating that propylene glycol is really industrial antifreeze and the major ingredient in brake and hydraulic fluids. These sites also state that tests show it to be a strong skin irritant. They further point out that the Material Safety Data Sheet (MSDS) on propylene glycol warns users to avoid skin contact because systemically (in the body) it can cause liver abnormalities and kidney damage.
As ominous as this sounds, it is so far from the reality of cosmetic formulations that almost none of it holds any water or poses real concern. It is important to realize that the MSDS sheets are talking about 100% concentrations of a substance. Even water and salt have frightening comments regarding their safety according to the MSDS. It is true that propylene glycol in 100% concentration is used as antifreeze, but—and this is a very big but—in cosmetics it is used in only the smallest amounts to keep products from melting in high heat or freezing when it is cold. It also helps active ingredients penetrate the skin. In the minute amounts used in cosmetics, propylene glycol is not a concern in the least. Women are not suffering from liver problems because of propylene glycol in cosmetics.
And finally, according to the U.S. Department of Health and Human Services, within the Public Health Services Agency for Toxic Substances and Disease Registry, "studies have not shown these chemicals [propylene or the other glycols as used in cosmetics] to be carcinogens" (Source: ATSDR Home).
Polyethylene glycol (PEG) is another ingredient "natural" Web sites have attempted to make notorious. They gain a great deal of attention by attributing horror stories to PEG. For example, several Web sites state the following: "Because of their effectiveness, PEGs are often used in caustic spray-on oven cleaners, yet are also found in many personal care products. Not only are they potentially carcinogenic, but they contribute to stripping the skin's Natural Moisture Factor, leaving the immune system vulnerable." There is no research substantiating any of this. Quite the contrary: PEGs have no known skin toxicity. The only negative research results for this ingredient group indicate that large quantities given orally to rats can cause tumors. How that got related to skin-care products is a mystery to me.
0 user(s) are reading this topic
0 members, 0 guests, 0 anonymous users