I'm back with another one of our Ingredient Truth series blog posts and this time I'm tackling the two most commonly used forms of sulfates: Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES). Why should you care? Well there's a lot of mixed info about their safety on the internet and since these two ingredients, according to some industry experts, can be found in close to 90% of shampoos and body washes, I think it's important to understand them. So is something this commonplace toxic for you? Well yes and no - I'll get to that below.
What are Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES)?
Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES) are found in products such as toothpaste, shampoo, facial cleansers, body washes, shaving foam and household cleaning products. They are surfactants and emulsifiers. In non-technical terms surfactants are what make your products foam or lather. In technical terms surfactants lower the surface tension between two liquids or a liquid and a sold. Emulsifiers are a bit easier to understand, they help keep ingredients in a product mixed together.
SLS and SLES can be derived from petroleum oil, coconut oil or palm oil. SLS becomes SLES through a chemical process called ethoxylation. So as you can see, there are a few ways to make them.
Should I Be Concerned?
The US Food & Drug Administration (FDA), the European Union, Health Canada, The Cosmetic Ingredient Review and Ecocert all consider SLS and SLES to be safe ingredients. That said, many articles quote studies that show both SLS and SLES can cause skin irritation, eye damage, diarrhea, respiratory damage, cancer – even death – in laboratory animals. Yikes that sounds pretty intense and extra crazy if many personal care products are using these two ingredients! But a deeper look at least at the animal deaths (it's sad to see animals still being treated this way) showed:
"Many of the studies on laboratory animals have involved applying SLS directly to the eyes of the animals and feeding them straight SLS. As would be expected with ANY chemical, eating it or putting it in your eyes would be bad news! Even natural substances applied in high concentration (for example, cinnamon oil or oregano oil) can have harmful effects."
Nevertheless, SLS by itself is sometimes used in lab testing to intentionally harm skin as a way to test other healing products or as a baseline to compare untested products to. Additionally Yves Lanctôt, a chemist and product consultant in Canada said:
"while SLS and SLES are not sensitizers — molecules that cause allergic reactions — they are irritants
and in some people can temporarily aggravate the skin, causing redness, dryness and itching"
There are also concerns regarding derivatives and byproducts of SLS and SLES. According to some, SLS and SLES have the potential to interact and combine with other chemicals to form nitrosamines, a carcinogen. However I've also found a number of articles disputing this fact including a chemist who said:
"As a chemist I have dug around on this one. How can SLS or SLES be Nitrosatable and create nitrosamines? They don’t even contain the element nitrogen in their structure – look for yourself on the wikipedia SLS entry. Nitrogen is not even used in the manufacture of either products so it would even be hard for nitrosamines to be present as contaminants."
The jury seems to definitely be out on this topic. But everyone, including the US FDA, agrees that a potential carcinogenic byproduct of SLES is 1,4-Dioxane. 1,4-Dioxane can sometimes arise during the ethoxylation process of SLS into SLES. Now even though the US FDA concludes that 1,4-Dioxane is a toxic containment it does not believe the ingredient is harmful at the levels present in cosmetic products:
"The levels at which a chemical compound would be considered harmful in a cosmetic depend on the conditions of use (FD&C Act, section 601(a)). The 1,4-dioxane levels we have seen in our monitoring of cosmetics do not present a hazard to consumers."
Even though the FDA doesn't regulate this ingredient, they did provide guidance to manufacturers on the potential health risks and how to minimize the level of 1,4-Dioxane.
Health Canada also reviewed 1,4 Dioxane in 2009 and agreed it is not harmful at the level found in personal care products:
"that adults’ exposure to it through personal care products is thousands of times lower than the levels that could affect our health. Children’s exposure levels were even lower."
However even with such low levels in our body, we say why not try to reduce interaction and ingestion further?
Does Block Island Organics Use SLS or SLES?
No our products do not contain these ingredients. Even though the debate on SLS and SLES is still on-going - we believe in airing on the side of safety.
How Do I Avoid These Ingredients?
Always read your product labels! Look out for their names sodium lauryl sulfate or SLS and sodium laureth sulfate or SLES on your label. In addition there are other commonly used names for SLS and SLES that you can find on The Environment Working Group's site here (SLS) and here (SLES).
