2D structural formula of Sodium lauryl sulfate


What is it?

Not to be confused with sodium laureth sulfate. Jump down to “sodium lauryl sulfate vs. sodium laureth sulfate” to learn more.

“Sodium dodecyl sulfate, synonymously sodium lauryl sulfate (or laurilsulfate; SDS or SLS, respectively), is a synthetic organic compound with the formula CH3(CH2)11SO4Na.” –Wikipedia

Sodium lauryl sulfate side effects?

This substance belongs to the groups:

Another name for this chemical is sodium dodecyl sulfate (SDS), and included in this substance group is also sodium coco sulfate (SCS), as it partly consists of SLS, thus shares a similar structure and risks.

Is sodium lauryl sulfate bad for you?

So, the first question, is sodium lauryl sulfate bad for you? The Ingredient Scanner says Yes. Here are 3 arguments why.

Firstly, the European Chemicals Agency (ECHA) classifies SLS as:

“harmful if swallowed, causes serious eye damage, is harmful to aquatic life with long lasting effects, is a flammable solid, is harmful if inhaled, causes skin irritation and may cause respiratory irritation.”

Secondly, it is likely that SLS contain inexpensive palm or coconut oil. Palm oil is a controversial ingredient as its cultivation cause environmental destruction, animal extinction and serious health concerns for the people working and living in the vicinity.

Unfortunately, it is normally not possible to check what kind of oil is used by just looking at the list of ingredients. Consequently, our Ingredient Scanner classifies this as contamination as it is “hidden” within the ingredient.

Preferably, it is stated on the product or in the product description if it is “palm oil-free” (or contain organically sourced oil). And if you can not find it, you can choose from two options:

  1. Assume that the product contains palm oil. Marketers know that a “free of”-stamp is powerful and will likely drive more sales and will, therefore, add it whenever and wherever it is possible.
  2. Ask the manufacturer, call or email, or go to their website to find out how they source their ingredients.

Thirdly, sodium lauryl sulfate chemical formula makes it a harsh cleansing agent in cosmetic* products. For many, it is much too aggressive.

In fact, all products containing sulfates are known to be very effective cosmetic cleansers. It does not only remove dirt but is also liley to strip body, skin, and scalp of its natural essential oils.

Is sodium lauryl sulfate bad for hair?

Yes. By cleaning so aggressively sodium lauryl sulfate shampoo damages hair, makes hair dry and also strips color of colored hair faster.

Is sodium lauryl sulfate bad for your skin?

Yes. Apart from making skin unnecessary dry, the ingredients are also known for causing skin, scalp and eye irritation.

Therefore, even if you can handle products containing SLS on your skin, it is advisable to switch to a milder alternative. Mainly to avoid developing sodium lauryl sulfate allergy or irritation later.

Sodium lauryl sulfate vs. Sodium laureth sulfate – what is the difference?

As we now know, SLS can be a harsh ingredient. So what the chemists did, to make it less irritatingand aggresive, was to add another chemical called ethylene oxide to SLS. This process is called ethoxylation.

In this process, sodium lauryl sulfate (SLS) becomes sodium laureth sulfate (SLES).

However, while the ethoxylation makes the chemical, in this case SLS, milder it also leaves trace amounts of the toxic ethylene oxide. The ethoxylation also creates another toxic by-product, the chemical 1,4- dioxane. Both by-product chemicals are carcinogenic.

So while SLES is milder and less aggressive than SLS in the instant that you are using a product that contains it, in the long term, it can cause more serious adverse effects.

Sodium dodecyl sulfate uses

Sodium lauryl sulfate (SLS), or sodium dodecyl sulfate (SDS), can be found in higher concentrations in laundry and cleaning products as it is effective for removing oil.

In cosmetics it is a popular chemical for manufacturers as it is cheap to produce and works as a:

  • Foaming agent – lathers.
  • Surfactant agent – lowers the surface tension of the cosmetic and helps with even distribution of the product.
  • Thickening agent – increase the viscosity.

Sodium dodecyl sulfate products

You can find SLS / SDS in all kinds of cosmetic and household products, including:

  • Facial cleansers
  • Shampoo
  • Liquid detergents
  • Bubble bath products
  • Dish soaps
  • Toilet cleaners
  • Toothpaste
  • Shaving creams

Our advice,

When you can, always try to avoid SLS and all other sulfates in the products you buy. If you find a product, for example, labeled “sodium lauryl sulfate free shampoo” or “sodium lauryl sulfate free toothpaste”, read the ingredients list anyways.

As we now know, there are sulfates or other names for the same ingredients, including sodium dodecyl sulfate (SDS) and sodium coco sulfate (SCS), that share the same or similar effects that might have replaced the SLS because of its bad reputation.

We use the European Commissions definition of Cosmetics:
“Cosmetics range from everyday hygiene products such as soap, shampoo, deodorant, and toothpaste to luxury beauty items including perfumes and makeup”.

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