Sunday, November 16, 2014

Ingredient Investigation: Limonene

Hey, beautiful people! As I mentioned in a previous post, I picked up some As I Am products during an early sale. While looking through the ingredients, I noticed that a lot of them have Limonene listed as the last ingredient, which I assumed was a preservative. However, I decided to dig a little deeper.

Limonene is made from citrus fruits (d-limonene), pine trees and certain mint plants (l-limonene). For cosmetic purposes, it is usually used as a fragrance. It is also used in medicines, botanical insecticides, household and other cleaners as a solvent, and water-free hand cleansers.

In terms of risk, while some research indicates that limonene can be used to treat cancer, other research indicates that it could promote the growth of tumors. The biggest issue, however, is that limonene can be a contact allergen. In other words, it can cause skin irritation or respiratory irritation in some people. Additionally, it can enhance side effects of other skin irritants, such as alcohol. As a result of the limonene’s irritant aspects, the European Union has put certain restrictions on its use in cosmetics. It is one of the contact allergens found in fragrances that must be listed if it exceeds 0.001% in leave-in products and 0.01% in rinse-off products. However, just because limonene is listed in an ingredient list, doesn’t mean it meets this threshold amount. Some consumer-conscious companies list it as an ingredient to notify their customers that they may have a potential allergic reaction. Additionally, just because a product doesn’t list limonene doesn't mean that the product doesn’t contain limonene, especially if there is a generic reference to “fragrance” and the product has a lemon or orange scent.

Based on what I’ve read, I’m fine with using products with limonene because I don’t seem to have an allergic reaction to it. I use a lot of products with lemon or orange oil, which are high in limonene, and I haven’t had an issue. I’ve also used As I Am products without issue.

As a final note, limonene should not be confused with Lemonene (also known as Biphenyl), which comes from coal tar, crude oil, and natural gas, and is used as a preservative to preserve citrus fruits during transport. Lemonene is mildly toxic.