When I had finished a recent presentation on avoiding toxins in our world, we opened the phone lines for questions. One of the subjects that kept coming up was sodium laureth sulfate.
Several callers were looking at the ingredient labels on their products and asking, “Is it safer if it comes from coconut?” Or, “What about sodium oleic sulfate?” And, “What’s the difference between sodium laureth sulfate and sodium lauryl sulfate?”
What is Sodium Lauryl Sulfate?
To put it simply, sodium lauryl sulfate and similar chemicals are surfactants-cleaning ingredients. If you want to get chemical about it, they’re the result of mixing lauryl alcohol with sulfuric acid, and then adding sodium carbonate. The resulting ingredient is used in carpet cleaners, engine degreasers, car wash liquids, and machine wash detergents because it’s highly corrosive and can remove oil and grease.
These ingredients are also used in a wide variety of personal care products, including soaps, shampoos, body washes, toothpastes, cleaning products, and anything else we like to “foam up.” They lower the surface tension of water and act as dispersal agents, helping to properly mix the ingredients in fragrance oils and body sprays. These properties also make these chemicals popular in moisturizing lotions and sunscreens.
The Difference Between Lauryl and Laureth
These are the two most common types that you’ll see in personal care and cleaning products. Both are irritating surfactants. The difference is in how they’re processed.
Sodium lauryl sulfate (SLS) is a good cleaning product, but is a skin irritant. It can cause damage to the skin barrier/outer layer of skin by disrupting the function of skin proteins and causing itchy, cracked, and dry skin. In shampoos, this ingredient can increase risk of scalp irritation, stinging eyes, and tangled, split, frizzy, and dull hair. According to the Journal of the American College of Toxicology (1983, Vol. 2, No. 7) researchers noted, “The longer these ingredients stay in contact with the skin, the greater the likelihood of irritation, and in need of repair to the skin barrier, which may or may not be evident to the user.”
The study authors go on to note that sodium lauryl sulfate causes “severe epidermal changes” to the area of the skin where it was applied. They also said that the detergent tended to deposit heavily on the surface of hair follicles, and that, “damage to the hair follicle could result from such deposition.” Finally, they noted that 1–5 percent sodium lauryl sulfate produced “significant number of comedones,” which are, essentially, whiteheads or blackheads.
The researchers concluded that SLS “appears to be safe in formulations designed for discontinuous, brief use followed by thorough rinsing from the surface of the skin. In products intended for prolonged contact with skin, concentrations should not exceed 1 percent.”
A Chemical Manufacturing Process
What about sodium laureth sulfate (SLES)? Though very similar to SLS, it is slightly different. It’s also a surfactant, and is used in products for the same reason that SLS is. It’s less irritating to skin and hair, however. Why? Because of how they process it.
To make SLES less irritating, manufacturers put it through a process called “ethoxylation.” (That’s why the “eth” in the name-any name that has “eth” has likely been ethoxylated.) Essentially, this means that they add ethylene oxide to the mixture to modify the chemical compound.
Ethylene oxide is a flammable, toxic gas used in the production of several industrial chemicals. According to the Occupational Safety & Health Administration (OSHA), acute exposure can result in respiratory irritation, headaches, nausea, cancer, reproductive effects, mutagenic changes, neurotoxicity, and sensitization.
Adding ethylene oxide to SLS, without getting into more complicated chemistry, reduces the irritation level of the ingredient. Many manufacturers use SLES rather than SLS for this reason-the ingredient is supposed to be gentler on the skin and hair. Because of this processing technique, however, SLES can be even more dangerous.
Basically, adding ethylene oxide to make an ingredient milder is a cheap short cut used by companies to avoid paying for more natural, nourishing ingredients. The problem is that ethoxylation produces a chemical called “1,4-dioxane” as a byproduct. 1,4-dioxane is a known cancer causing agent and a leading groundwater contaminant, according to the Environmental Protection Agency (EPA). It readily penetrates the skin, and is included on California’s Proposition 65 list of chemicals known or suspected by the state to cause cancer or birth defects.
Of course, shampooing your hair once or twice will likely cause you no harm. The problem is, we use products with these ingredients several times a day, every day. Check your ingredient labels. You may be surprised at how many products contain SLS or SLES.
Where Do They Come From?
What if the label says the ingredient comes from coconut?
What they’re talking about here is where they’re getting the raw materials-in this case, the lauryl alcohol. Getting back to chemistry, SLS is synthesized in the lab by treating lauryl alcohol with sulfur trioxide gas or chlorosulfuric acid. Lauryl alcohol can come from petroleum, but it can also come from coconut oil. The oil is put through an elaborate process, however, that liberates the fatty acids, then hydrogenizes the oil, then pulls out the lauryl alcohol.
No matter where the alcohol comes from, it’s still mixed with the other chemicals to produce SLS or SLES or other forms of the ingredient. The result is still a chemical that is a long way from the original coconut oil. We may feel better having something that originated from coconut oil rather than from petroleum, but that doesn’t mean the chemical will not be irritating to skin or hair, or that it will not be contaminated from manufacturing processes.
How can we be sure of the extent of the contamination? We have no way of knowing. Companies can “vacuum-strip” ingredients to take the 1,4-dioxane out, but you won’t find anything on the label telling you whether or not they did that.
The whole “coconut-derived” or “from coconut oil” or whatever verbiage you see on the label is a marketing gimmick to make you believe that somehow the ingredient is more natural. Don’t fall for it! Choose instead products that have REAL natural ingredients rather than chemicals they’re trying to pass off as “more natural.”
What About Different Types of Sulfates?
As we were discussing this issue on our call, people started asking, “Well what about this x-y-z-sulfate, or this tri-something-di-sulfate?”
It’s true that there are many other sulfates out there used in personal care products. As the public grows wise to SLS and SLES, manufacturers are switching to other types, again, hoping to fool us into thinking they’re watching out for our safety.
Sodium lauryl sulfate is also called sodium dodecyl sulfate (SDS). Sodium coco-sulfate is another very similar ingredient-the only difference is that instead of using just one lauryl alcohol to start with, they use a blend of fatty acids from coconut oil, react them with sulfuric acid, then sodium carbonate, to create sodium coco sulfate.
Other similar names include:
- Sodium caprylic sulfate
- Sodium capric sulfate
- Sodium oleic sulfate
- Sodium stearyl sulfate
- Sodium myreth sulfate
- Sodium dodecanesulfate
- Sodium monododecyl sulfate
- And more!
These are all named according to the particular isolated fatty acid used to start the chemical process in the first place.
Bottom Line
This is a lot of chemistry to get into over just one ingredient. What really matters is the manufacturer. Are they using cheap chemicals and trying to pass them off as natural, or are they using truly natural ingredients that you can actually pronounce? Typically if you see one potentially harmful chemical like SLS or SLES, you’re going to see more, like formaldehyde-containing preservatives (ureas) and nitrosamine-forming agents (triethanolamine).
The key is not to think you have to become an expert at every chemical ever used in personal care products. Instead, find brands you trust. Find brands that have been conscious about safety from the beginning. Find brands that believe in using real natural ingredients that support skin barrier repair and protection. Buy from them, and forget about it!
Have you found sulfate-free formulas that you like? Please share!
Picture courtesy DJOtaku via Flickr.com.
Sources
National Toxic Encephalopathy Foundation, “SLS,” http://www.national-toxic-encephalopathy-foundation.org/wp-content/uploads/2012/01/sls.pdf.
OSHA, “Ethylene Oxide,” http://www.osha.gov/SLTC/ethyleneoxide/index.html.
Natural Health Information Center, “Sodium Lauryl Sulfate (SLS) and Sodium Laureth Sulfate (SLES). The Killers in your bathroom?” http://www.natural-health-information-centre.com/sodium-lauryl-sulfate.html.
Chemical of the Day, “Sodium Coco Sulfate,” http://chemicaloftheday.squarespace.com/qa/2011/9/26/sodium-coco-sulfate.html.
David Suzuki, “Sodium Laureth Sulfate,” http://www.davidsuzuki.org/issues/health/science/toxics/chemicals-in-your-cosmetics—sodium-laureth-sulfate/.
Campaign for Safe Cosmetics, “1,4-dioxane,” http://safecosmetics.org/article.php?id=288.
Hello, thanx for the fantastic info. I recently came over a shampoo that is eco certified, it contains 3 different sls, but they say that the sls has been extracted from coconut fat, with just ecological beat roots, and nothing else. My question is if it this possible, and if does the same damage as any sls? I feel like they are just trying to confuse us some way….
Have a nice one!
Hi, Lawrence. Yes, the marketers like to fool with our heads! The thing is that no matter what raw materials they use, they’re still creating the same basic chemical and it can still be very harsh on the skin and hair. I would always recommend you avoid it completely for that reason. There are a lot of shampoos out there these days that are sulfate-free. Just Google “sulfate-free shampoo” and you’ll find several options. Good luck!
“Instead, find brands you trust. Find brands that have been conscious about safety from the beginning. Find brands that believe in using real natural ingredients. Buy from them, and forget about it!”
Britta Aragon, you have GOT to be kidding. Apparently in your view no one has ever abandoned their moral standards for the right amount of cash. Blindly trusting a brand is stupid, foolish, and dangerous. ALWAYS read the ingredient label before you use or ingest every product.
I have been reading ingredient labeles for decades, and saw products on may occasions whose safe ingredients were taken out in favor of dangerous ingredients.
Hi, Sally. Thank you for your input. Actually, we totally agree on reading labels! I am always advocating that on my blog and in my workshops. If you read the entire post, however, you’ll see that it was written in response to questions I had received on this ingredient from attendees to my presentation who were getting overwhelmed with all the various chemicals found in today’s products, and how manufacturers are trying to pass some off as being safer than they are by saying “from coconut.” These attendees were thinking they had to know every single chemical in a product, where it came from, whether or not it was toxic, etc.
Sure, if you’re willing to put in the time and research, becoming knowledgeable about all that is great. I provide this blog to help people do just that. But what if you’re not? What if just don’t have the time, or it’s all too confusing? For some people, constantly trying to learn the difference between one chemical and another can get discouraging, and they eventually give up on the whole endeavor.
My main goal is to help people easily find products that are safer for them and their families. I have found in my many years of researching products, ingredients, and brands, that some companies do stand out as being completely conscientious and caring when it comes to using safe ingredients. Examples include Marie Veronique Organics (http://cincovidas.com/cancer-survivor-finds-skin-care-company-to-believe-in/) Suki Organics, and my own CV Skinlabs. Finding companies like this to purchase products from can take a lot of the work out of shopping for personal care, and that means people are more likely to use safer products. Of course, as you say, reading labels is always advised, but if you’re starting to scratch your head wondering if sulfate from coconut is better than regular sulfate, in my opinion, it’s time to take a step back and make it easier on yourself. We don’t all need to become chemists—we just need to learn the general idea of finding products with good ingredients.
Thx for the information
Hi, Pauline. Congratulations on your efforts! We definitely need more people spreading the word about safe, nourishing products. We don’t review products here at Cinco Vidas, but I applaud you in your work and encourage you to keep going. More and more people these days are wanting nourishing products. The tide is slowly turning. Good luck!
Thanks for this great article. As a rep for Miessence I often get questions like this. Your point is spot on – if they use nasties like Sodium Cocoyl Isethionate then there are sure to be other chemicals hidiing in their recipes. I also agree with finding companies you can trust and that actually put money into third-party certifications. Miessence is a company that prides itself on its ability to be tranparent because of this certification: http://kimnightingale.miessence.com/
Thanks for your comments, Kim. So glad you’re helping to spread the word on these types of ingredients that just aren’t good for us, and frankly, just don’t need to be in our skin care. Best of luck!
Britta, thank you for being so thorough in your explanation of the differences of these ingredients. I was trying to find the chemical difference in these particular sulfates (why they called them different things) and you spelled it out perfectly for me. I appreciate all the time you took to research and share this information. I even learned one thing to help with other questions I’ve had unanswered that I hadn’t researched and will implement to better choose my products going forward. Thank you, again.
I recently became a consultant for Arbonne Canada and was posed with the question about SLS as the client had some irritation to it. In researching and asking others I discovered and was more confused by the ‘Lauryl’ and ‘Laureth’. I knew Arbonne didn’t use SLS in their products but I needed to know more. So I went on the search and found your sight. WOW! Thank you for making that so much clearer. I looked at our ingredient list and we are still free!! We use Sodium Cocoyl Isethionate, a coconut oil based cleansing agent. I did research this as well (had to make sure) and the sites I have come across, including EWG all deem it safe. I joined Arbonne because they are a Vegan certified company aiming to provided pure, safe and beneficial products and I am glad they continue to come up aces!
Thanks for this extensive explanation. What a confusing topic, when we ought to be able to read a label without so much worry. I’m telling folks they need to check out this article.
Hi Britta,
I was a participant in the Webinar & remember these questions. Thank you for researching these issues and detailing the information in such a clear, articulate, understandable manner. This information is very helpful as I begin the purging process of the many products I have that contain these unsafe chemicals.
As I seek replacements of such products, I first go to http://www.ewg.org/skindeep/ to find non-toxic, chemical free alternatives. For my laundry, I have been using soap nuts now for about 9 months and have been very pleased with the results. The following website is full of useful information about soap nuts: http://www.soapnuts.pro.
Again, thank you for your research & diligence in the fight for safe personal products.
Lisa McNichol
Hi, Lisa!! Thanks so much for attending the workshop, and for sending your feedback here! I’m so happy to hear that this blog helped you, and that you’re making changes for your health. My hat’s off to you for ridding your life of potentially harmful chemicals. Thanks for the tips on laundry—I’m sure our readers will benefit. Good luck!