Toxic Thursday: SLS/SLES

Thursday, March 13

I've been putting off writing this post for a while, as the use of SLS/SLES is such a controversial topic in the cosmetics industry that there is just so much to cover. I didn't think I'd be able to do it justice or sufficiently cover all areas of concern, however I've decided to give it a go and add my voice to the roar of the argument!

What is the difference between SLS and SLES? 
SLS is Sodium Lauryl Sulphate, a surfactant used in almost every foaming cleaning product available such as body wash, shampoo, toothpaste and industrial cleaners.
Some companies add Ethylene Oxide to Sodium Lauryl Sulphate to make it less toxic and irritating, and this formes SLES, known as Sodium Laureth Sulphate. This has complications of it's own which I'll discuss further down.  They clean by stripping a protective layer of lipids from your skin and remove the dirt trapped there.

Why do people have issues with SLS/SLES? 
Sodium Lauryl Sulphate is a known irritant, and can cause allergies and eczema in susceptible people. It can cause scalp irritation and itching, as well as a burning sensation and excess dandruff. Many people have issue with the use of SLS in industrial cleaners, and the subsequent use of it on our bodies. Also, SLS is used purposefully as an irritant in animal studies. When researchers need to directly irritate the skin or the eyes of the animal, they use SLS. There are also concerns that SLS reacts with other compounds found in body care products, forming nitrosomines. These are potential carcinogens.

Other concerns around SLS are it's effects on the environment. It's a known pesticide and insecticide, and has been classed as 'inherently toxic to aquatic life' by the Environment Agency in Canada. The producers of SLS recently tried to have SLS allowed as a pesticide in organic farming. This was denied however, due to the detrimental impact this chemical has on the environment and vulnerable life forms.

To reduce the toxicity of SLS, some companies add Ethylene Oxide, which can form a carcinogenic known as 1,4 Dioxane. The Cosmetic, Toiletry and Fragrance Committee advise against prolonged use of SLES, and the Agency for Toxic Substances & Disease have found that long term skin exposure can cause organ damage (liver & kidneys), tumour growth and cancer. The US Food & Drug Administration have called for the levels of 1,4 Dioxane to be monitored, and the FDA encourage the removal of this compound from products, including cosmetics. It's not a legal requirement however.

In addition to the 1,4 Dioxane, many people believe that SLES causes hair loss over time, and that it reduces the hair growth cycle. These last two points are still speculation, yet Jennifer Disomma, the head of Product Development at L'Oreal, stated that sulphate free shampoos are much gentler on the hair fibre and less likely to cause damage.

So SLS is used in industrial cleaners, and we put it on our bodies?!
Yes. Also the same sodium chloride they industrially spray over concrete in the winter is the same as  we put on our food; the same H20 used in any industrial process including oil extraction is the same as in your drinking glass. The use of something 'industrially' does not inherently mean it's bad or dangerous for us. Perhaps what is more concerning is not where SLS is used, but how it actually works. It cleans by corrosion, by stripping away natural oils and leaving the skin open to pollution and dirt from elsewhere. It's true that our bodies can quickly generate a new protective layer, yet we risk upsetting the balance of our bodies' natural cycle, encouraging excess oiliness or dryness where there would otherwise be a natural regulation.

If SLS/SLES are as dangerous as they sound (particularly SLES and 1,4 Dioxane), why are they still allowed in our products? 
If something is harmful to us, that is not reason enough for a government to ban use of  it. It's why we can buy cigarettes, even though we know without a shadow of a doubt that they directly cause lung and throat cancer, as well as being potentially fatal to those around us. Companies give us information, and we make a choice. Research into cosmetic ingredients is relatively new, and it's going to be a long time before any ingredient has the scientific research behind it for researchers and governments to make any definitive conclusions about it's use in our products.

The argument for and against SLS/SLES is not straightforward, and if the only issue was that they are irritants, then I still think it would be acceptable to use it.  I never had issues with scalp sensitivity or irritation, although I definitely cut out SLS/SLES in my products now. For me, it comes down to both SLS/SLES being a harsh synthesised chemical, which disrupts the balance of oils in our skin. It's unnecessary and I feel that it's detrimental to the health of my body. I say I never had any sensitivity or skin issues, but in reality my skin was not perfect. It was oily, congested and spot prone, and as I've switched to an organic skin care routine, my skin has felt for the first time in my life, healthy, balanced and happy. I think many people might have issues caused by SLS/SLES that they think is just normal for them. The links to cancer, particularly with SLES, also concern me - however tenuous they may be. There are so many synthesised chemicals, literally hundreds of thousands, that when researchers and regulators begin to raise concerns about the safety of a couple, I listen up. We all have to do our own research and make our own conclusions. Play your own devil's advocate and bring up every counter argument you can think of.

I struggled for a while to truly see why people avoided SLS/SLES as I thought it was just a marketing tactic. If any of you reading this are the same then I hope this post helps!

Is anyone else not directly affected by SLS/SLES but still cuts them out of their products for similar reasons? I'd love to hear what you think about the argument.

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  1. Great post! You've written this so well and its so informative :) I personally avoid SLS because I suffer from eczema and anything I use with SLS causes it to flair up, also with no actual benefits of using it I don't understand why people even still use it :)

    1. Ah thanks Amber :) I totally agree, it has zero benefits and plenty of problems, so I'm guessing people just don't know enough about it. Unfortunately I also think a lot of people would rather not know, and avoid the hassle it would bring. It's a shame cause I'm sure there's plenty of people who suffer but don't know why. Hope being SLS free is helping your eczema :) x

  2. Great post, I'm the same as Amber ditch it because of my eczema, once I realised the trouble it causes me I was happy to let it go.

  3. I certainly have found my eczema and dandruff have certainly improved since not using them.

  4. Hi Chesca,
    It's great to see conversations like this going on regularly about skincare ingredients and their implications, or otherwise, to the health of our skin. It is a really complex area that we as a professional skincare company are really happy to engage with, it's so important that open dialogue and critical discussion is allowed, we need sensible debates and discussions to cut through the noise of what is becoming a cacophony of wildly differing voices! You balanced and questioning approach is refreshing.

    Our advice is to do your own research, look for reliable sources and get to know how to read and interpret the results published from lab studies - they are purposefully designed to establish upper safety limits and beyond, ingredients are commonly used at levels way below than those tested in studies . Knowing your own skin is also important - eczema for example is a complex whole system reaction that can be affected as much by what we're putting into our bodies as what we're putting onto them. If products are left on the skin or hair or are not properly rinsed, this can also be the root of the reactions or irritation. It's the method and application as well as levels that are important.

    Thanks again,