Petrochemicals
Dioxane
Dioxane is not a petrochemical, but it is the byproduct of petrochemicals. Officially it is known as 1,4-dioxane, but is usually referred to as just dioxane. Dioxane is not added to skin care products as an ingredient, but is a byproduct of the manufacturing process. Because of this, the FDA does not require dioxane to be included in the list of intentionally added ingredients. As a result, there is no way to know for certain how many products contain it. Therefore, consumers are not aware of it and do not know why or how to avoid it.
It is only because of the work by third party product testers and non-profit groups that we know the extent of its use. The Environmental Working Group released the report, Skin Deep in which they tested over 22,000 skin care products. Their analysis found that 22% of the products they tested contained dioxane, including many brands of baby shampoo, children’s bubble bath and body wash. Dioxane can also be easily absorbed through the skin.
So you have a widely used chemical byproduct that can be easily absorbed through the skin. But what is the risk to humans? Dioxane is considered a probable human carcinogen by the U.S. Environmental Protection Agency and listed as an animal carcinogen by the National Toxicology Program (a carcinogen is any substance that is directly involved in causing cancer). It is included on California’s Proposition 65 list of chemicals known or suspected by the state to cause cancer or birth defects. The California Environmental Protection Agency also lists dioxane as a toxin to kidneys, lungs, and the nervous system. Though dioxane itself is not listed, you can tell which products may contain it by scanning the ingredients list and looking for the chemicals which usually contain the impurity. According to the FDA, these chemicals can be identified by the prefixes or designations of “PEG,” “Polyethylene,” “Polyethylene glycol” “Polyoxyethylene,” or “–oxynol.“
Dioxane is most frequently found in products that create suds. This includes, but is not limited to, shampoo, liquid soap, and face washes. This means that when you wash your face with a sudsy wash, you may very well be slathering dioxane directly onto your pores to permeate through the skin tissue – and you won’t ever know it.
Methylisothiazolinone
Methylisothiazolinone, also known as MI is widely used in personal care products such as shampoos, hand creams, lotions and cosmetics. It is a preservative that controls the growth of bacteria, mould, and fungi. MI is also used to protect the colour and consistency of products. This is another case of “production over protection”.
MI has been associated with allergic reactions including dermatitis and eczema, and these allergic reactions in turn are known to cause irritation to the eyes, skin and lungs. It has the dubious distinction of being the American Contact Dermatitis Society’s “Contact Allergen of the Year” for 2013.
Though long presented by the manufacturers as safe for use in cosmetics, a recent in vitro study has shown that MI alters the normal activity of the nervous system in such a way as to cause damage to nervous tissue. The study showed that it caused damage to rat brain cells in tissue cultures. Some studies have shown MI to be allergenic and toxic to cells, and this has led to more concern over its use. In another study it was found that there is strong evidence of it being a human sensitiser, toxicant and allergen. MI is prohibited in Canada, and Japan has restrictions on certain uses in cosmetic manufacturing.
