A.A. Constantine's Persian Healing or Pine Tar Soap was patented on March 12, 1867, but pine tar soap had been in use much earlier. In this century, our concern with the role chemicals and toxins play in damaging the environment and our health has led us to look into the past for safer, cleaner, more natural products. Unfortunately, just because something's been around longer doesn't always mean it's safer.
Pine tar is made from carbonizing pine stumps and roots at very high temperatures and pressure in a closed vessel. It has been used for centuries as a sealer for wooden boats, in roof construction and as an ingredient in soaps and shampoos. Pine tar is also used to treat some skin diseases,such as rosacea, eczema and psoriasis. By itself, if manufactured properly, pine tar poses no health risks.
Different pine tar soaps contain different things. The main ingredient is pine tar or pine oil, and this must make up at least 20 percent of the soap for it to be authentic. A recipe for homemade pine tar soap from BellaOnline.com calls for coconut oil, olive oil, pine tar, lye and water or other liquid.
Of the two best-known commercial pine tar soaps, Packer's Pine Tar Soap contains soap base, pine tar, pine oil, iron oxide and PEG-75. Grandpa's Pine Tar Soap contains coconut oil, palm oil, purified water, pine tar oil, (Pinus palustris) and vegetable glycerin.
None of these ingredients would seem to pose health risks, but two of them--PEG-35 and pine tar--require a closer look.
Most pine tar and pine oil is made using a closed-kiln process that keeps it pure. If pine tar is made in an open kiln, the smoke and little fragments of unburned wood can come in contact with the tar and result in the creation of creosote, a known carcinogen.
A 2003 study by the Scientific Committee on Cosmetic Products and Non-Food Products found that "wood tar and wood tar preparations do pose a health risk when used in used in cosmetic products."
For this reason, most commercially produced pine tar soaps say "Creosote-free" right on the label.
One potential toxin found in pine tar soap is 1,4 dioxane, also just called dioxane. This is not regulated by the Food and Drug Administration because it's not an ingredient itself; it's a byproduct of other ingredients. Studies done by the Agency for Toxic Substances & Disease Registry have shown that dioxane at high doses can cause kidney and liver damage, and has been proven to cause irritation to the nose and mouth when inhaled as vapor. According to the U.S. Department of Health and Human Services, 1,4-dioxane is "reasonably anticipated to be a human carcinogen."
Though most soaps and cosmetics contain only trace amounts of dioxane, some exceed the FDA's recommended exposure levels.
How to Avoid Toxins
As with anything you eat, drink or apply to your body, read the labels. Dioxane is a byproduct of the following chemicals, which are used to offset the harshness of other ingredients: PEG, polyethylene, polyethylene glycol, polyoxyethylene, polyethoxyethylene or polyoxynolethylene. Avoid buying pine tar soap containing these ingredients. Also, if the label doesn't say "Creosote free," don't buy it. Or, contact the manufacturer and ask if the pine tar it uses is made via closed-kiln or open-kiln. Avoid soaps using open-kilned pine tar.