Shampoo Detergents: ALS, ALES, SLS and SLES

[Ursula]

Finding the right shampoo, if you want to use one, can be a matter of great stress for an LHC member. Formulas can be complicated, and there are a variety of detergents used in shampoos.

Someone mentioned that we'd need our own personal chemists to figure out which of the four main shampoo detergents was the gentlest. Amonium Lauryl Sulfate, Amonium Laureth Sulfate, Sodium Lauryl Sulfate, or Sodium Laureth Sulfate?

Well, wouldn't you know, I happen to have my own personal chemist handy!

My very own father, who just happens to like long hair, and is amused that I hang out here. Also happens to have a PhD in chemistry.

Here's what he had to say:

Ursula, here is the info on lauryl and laureth sulfate. It took some time to get it off the internet. I feel that this information is reliable, since they stay away from hype. Some of the ‘anti’ internet information is total garbage, seen from a chemists point.

Both compounds are effective, but it seems that laureth is a bit safer. Ammonium usually makes the molecule more soluble and foaming than Sodium. Please, note that like all detergents, these may irritate the eyes, and may irritate the skin (‘allergic rash’, my terminology). As always, one must stop using these and try something else.
Dad. / Ingo H. L****** Dr.rer.nat.

Sodium dodecyl sulfate also known as sodium lauryl sulfate (SLS)

From Wikipedia, the free encyclopedia.

Sodium dodecyl sulfate (SDS or NaDS) (CH3(CH2)11OSO3Na) (FW 288.38 ), also known as sodium lauryl sulfate (SLS), is an ionic detergent that is used in household products such as toothpastes, shampoos, shaving foams and bubble baths for its thickening effect and its ability to create a lather. The molecule has a tail of 12 carbon atoms, attached to a sulfate group, giving the molecule the amphiphilic properties required of a detergent.

Sodium dodecyl sulfate

It is prepared by sulphation of lauryl alcohol (1-dodecanol, dodecyl alcohol,

(Note):

CH3(CH2)10CH2OH + H2SO4 -> -> CH3(CH2)10CH2OSO3 (-) Na(+)
Or NH4(+)

(Note: There is no sulfuric acid (H2SO4) in the final product, since all has been neutralized, see next)

followed by neutralization with sodium carbonate. It is used in both industrially produced and home-made cosmetics.

Like all detergent surfactants (including soaps), it removes oils from the skin, and can cause skin irritation. It is also irritating to the eyes.

SDS can be converted by ethoxylation to sodium laureth sulfate (also called sodium lauryl ether sulfate; SLES), which is less harsh on the skin, probably because it is not as much of a protein denaturant as is the unethoxylated substance.

In laboratories, SDS is commonly used in preparing proteins for polyacrylamide gel electrophoresis (SDS-PAGE). SDS works by disrupting non-covalent bonds in the proteins, thereby denaturing them, causing the molecules to lose their native shape (conformation). Also, anions of SDS bind to the main peptide chain at a ratio of one SDS anion for every two amino acid residues. This effectively imparts a negative charge on the protein that is proportional to the mass of that protein (about 1.4 g SDS/g protein). This new negative charge is significantly greater than the original negative charge of that protein. The electrostatic repulsion that is created by binding of SDS causes proteins to unfold into a rod-like shape thereby eliminating differences in shape as a factor for separation in the gel.

The critical micelle concentration in pure water is 0.0085 M, and the aggregation number at this concentration is around 50.

Categories: Chemical compounds | Household chemicals



Sodium laureth sulfate

From Wikipedia, the free encyclopedia.

Sodium laureth sulfate, or sodium lauryl ether sulfate (SLES), is a detergent and surfactant found in many personal care products (soaps, shampoos, toothpaste etc.). It is a cheap and very effective foamer.

CH3(CH2)10CH2(OCH2)nOSO3(-) Na(+)

Note: The (OCH2)n group makes it different from ‘lauryl’.

Sometimes the number represented by "n" is specified in the name, as laureth-n sulfate (unsubscripted), for example laureth-2 sulfate. The product of commerce is heterogeneous, both in the length of the alkyl chain (12 being the mode of the number of carbon atoms), and in the number of ethoxyl groups, where n is the mean. n=3 is a common article of commerce.

If SLES is not present, sodium dodecyl sulfate (SDS) (also known as sodium lauryl sulfate or SLS) or ammonium lauryl sulfate (ALS) will probably be.

There is a persistent but popularly unproven assertion that SLES is carcinogenic.

Sometimes listed as Steol-130, 230, 270, 330, 370 or 460; Stepanol; Alkyl Ether Sulfate; Sodium POE(2) Lauryl Ether Sulfate; Sodium Diethylene glycol Lauryl Ether Sulfate; Sodium Lauryl Ether Sulfate.


External links
http://www.checnet.org/healthehouse/...sp?Main_ID=285
Snopes Urban Legends Reference: Sodium lauryl sulfate
http://www.chemicalland21.com/arokor...%20SULFATE.htm

Categories: Household chemicals

And my own hair care analysis of his chemical analysis:

Laureth compounds will be gentler than lauryl compounds, as we've known for a while. This means gentle in the sense that the same amount of detergent will pick up less oil (and other dirt) if it is laureth than if it is lauryl.

Amonium compounds and sodium compounds will each be gentler than the other in different ways.

Amonium compounds will lather and dissolve better, and will rinse more easily. This will mean less residue. They will probably be more effective as a clarifier. The amonium detergents may be more gentle for you if you have problems with buildup or irritation from shampoo, since less will be left behind on your hair.

Sodium compounds will be less drying. This will be gentler if you have problems with your skin, scalp and hair getting too dry. But since sodium compounds aren’t as soluble, they may be more likely to leave residue, which could lead to irritation. You may also need to pay more attention to rinsing well with a sodium detergent shampoo.

A big part of how harsh or gentle the shampoo will be will depend on the concentration of the detergent, as well as the components. A more concentrated shampoo will be harsher than a dilute shampoo. This can not be judge with complete accuracy based on product labels, but in general, the farther down the list you find a detergent, the lower the concentration of that detergent in the shampoo.

As with any ingredient, it will take experimentation to find out which detergent will work best for your head and hair. But knowing whether you're more likely to have problems with sensitivity or drying will allow you to make an educated guess.

To summarize:

ALS - cleans thoroughly, rinses quickly and easily
SLS - cleans well, more gently than ALS, won't rinse as easily
ALES - cleans less thoroughly/more gently (depending on your POV), more thorough rinsing, good if you are sensitive to detergent residue
SLES - least thourough cleansing/very gentle cleaning (depending on your POV, less thorough rinsing, good if you have problems with over dryness, perhaps not good if you have product sensitivities, since product is more likely to be left behind on your head.

[Buddaphlyy]

Thanks for the article. Very informative.

[adalynn]

Great info. All my thanks to you and your dad. I now know exactly what I am using in my precious hair. As you already know shopping for products is a life long chore. I usually spend twenty to thirty minutes on a hair care aisle. This will help to make a quicker and MUCH more informed decision. THANK YOU!

[Jane of Upton]

Thank you for such great information! Well laid out, understandable, and concise!

Excellent!
-Jane

[paradoxx]

Thank you so much for this great information Ursula! Thanks to your dad as well!

[Mama K]

Thanks for this! I'm going to check my shampoo ingredients now...

[Keenkitty]

Which brings my question...What do SLS,ALES,SLE FREE shampoos have that cleanses the scalp without totally drying it out?

I find natural AMLA powder and Shikaikai Powder tend to wash just as well as commercial shampoos without any stripping...Do they still have one of these compunds?

Are one of these fours compounds absolutely nessecary to have a properly working shampoo?

Hrrrmmmmm????


KJ