Propylene Glycol, Sold by weight. Propylene glycol is one of the most widely used cosmetic ingredients, it is a humectant. It is a clear, colorelss, viscous liquid, slightly bitter-tasting. It is the most common moisture-carrying vehicle, other than water itself, in cosmetics. Absorbs moisture, acts as a solvent and a wetting ingredient. Use as a carrier to dissolve your dry colorants and create liquid ones.

The Department of Health and Human Services (DHHS), the International Agency for Research on Cancer (IARC), and the EPA have not classified propylene glycol for carcinogenicity.

Uses: (1) Moisturizer in medicines, cosmetics and food products. (2) Medical/sexual lubricant. (3) Solvent for food colors and flavorings. (4) Carrier in fragrance oils and melt and soap bases. (5) Antibacterial lotions and saline solutions. (6) Food, cake mixes, salad dressings, soft drinks, popcorn, food colorings, fat-free ice cream and sour cream. (7) Preservative in toiletries and cosmetics.

For those of you who may believe that propylene glycol means "antifreeze": antifreeze is made from ethylene glycol.

We have taken the liberty of copying this from Tom’s of Maine literature:

Propylene glycol is considered a safe and appropriate ingredient not just for cosmetic products, but also for ingested products like food and pharmaceuticals. It is on the US Food and Drug Administration's list of ingredients which are Generally Recognized As Safe (GRAS) and is recognized by the World Health Organization as safe for use.

There have been claims made that propylene glycol is an inappropriate ingredient for cosmetics and foods because it can also be used in products (such as antifreeze) which one would not want to consume. Such observations are well-intended but ultimately not very informative. It is ethylene glycol, for example, which is a more common ingredient in anti-freeze and which is, in fact, highly toxic. Simply because propylene glycol has many different applications does not make all the products which contain it the same.