Sulphate free shampoos and other personal care products have become fairly popular in recent years. But what are sulphates (or sulfates) in the first place? And why should you avoid them?
What are sulphates?
Sulphates are inorganic ions that are both found in nature and synthesised for industry. In the natural world, they occur as aerosols from biomass combustion and as part of the sulphur cycle of some microorganisms.
Sulphates are also the salts and esters of sulphuric acid, a highly corrosive acid. These compounds are valuable in many industries because they are very good detergents, emulsifiers, and foaming agents.
Are sulphates natural?
Sulphates are either derived from natural sources or synthetically produced. Sodium lauryl sulphate or SLS, one of the most common types of sulfates, can be made from plant sources such as coconut oil or palm kernel oil. But they can also be synthesised from nonrenewable petroleum sources.
What do sulphates do?
Sulphates are added to many products to make them more effective cleaners. They're surfactants — compounds that attract both oil and water. One end of a surfactant’s molecule is attracted to water and the other end is attracted to oil. This property allows surfactants to lift dirt and oil from your body. Sulfates break them down so that when you rinse, they simply go down the drain with the water.
Chemists first added sulphates to shampoos in the 1930s. Before their introduction, soaps and shampoos weren’t very good at cleaning. The addition of sulphates to shampoo thus changed the world of hair care forever.
Aside from making soaps and shampoos better at removing dirt and grease, they also gave these products the ability to lather. Foam isn't really necessary for cleaning. But since the addition of sulfates, people have come to associate suds with getting clean.
What kind of products contain sulphates?
Because sulphates are inexpensive and have many uses, they're in countless products. They're in a lot of personal care items, including soaps, shampoos, conditioners, body washes, toothpastes, and facial cleansers. They're in laundry detergents, dishwashing liquids, surface and carpet cleaners, car wash liquids, and other cleaning products that foam up.
Because they are such powerful surfactants, sulphates are a vital ingredient in the products used to remove grease from heavy machinery.
Body sprays, fragrances, sunscreens, lotions, and makeup may also contain sulphates. In these products, sulphates act as dispersal agents that allow the ingredients to come together properly.
How do you recognise sulphates?
There are many kinds of sulfates. The most common ones are:
- sodium lauryl sulphate (SLS),
- sodium laureth sulphate (SLES), and
- ammonium lauryl sulphate (ALS)
When you see the “sulphate free” label, it usually means that the product does not contain any of these three. However, now that the public has become more aware of the potential harm from these sulphates, manufacturers have begun swapping them with lesser known types.
Unfortunately, these other sulphates (and related chemicals) may be no safer than SLS, SLES, and ALS.
Look out for these other kinds of sulphates: sodium lauryl sulphoacetate, sodium capric sulphate, sodium caprylic sulphate, sodium monododecyl sulphate, sodium oleic sulphate, sodium myreth sulphate, sodium stearyl sulphate, sodium dodecanesulphate, sodium lauroyl isethionate, sodium cocoyl isethionate, sodium lauroyl sarcosinate, sodium lauroyl taurate, sodium lauroyl methyl isethionate, and disodium laureth sulphosuccinate.
What the experts say about sulphates
The Cosmetic Ingredient Review Expert Panel says that SLS is safe for use in cosmetics. SLES and ALS are also labeled safe, but the CIR recognises that these two can cause eye and skin irritation.
According to a study published in the Journal of the American College of Toxicology, SLS and ALS are irritants at concentrations of 2% and greater. The study shows that the severity of irritation increases with the concentration of the sulphates. It also concludes that the longer the ingredients stay on the skin, the greater the chances of irritation.
The study notes that SLS did not prove to be carcinogenic in experimental animals. However, it also says that “severe epidermal changes” were observed on the areas of the skin (of mice) on which SLS was applied. The study concludes that both SLS and ALS may be safe in products that will only be in contact with skin briefly and that will be followed by thorough rinsing. It recommends a concentration of less than 1% for products designed for prolonged skin contact.
SLS has an EWG score of 1-2 (depends on usage), SLES has a 3, and ALS has a 1. EWG notes that SLS and SLES can cause irritation of the skin, eyes, and lungs, and that there is moderate concern for organ system toxicity with all three sulphates.
Both ECOCERT and NATRUE have approved the use of SLS, ALS, sodium cetearyl sulphate, and sodium coco-sulphate in natural and organic cosmetics.
All of the above are on the COSMOS Raw Material Database, as are other types of sulphates, including zinc sulphate, zinc coco-sulphate, ammonium coco-sulphate, and magnesium lauryl sulphate. Australian Certified Organic uses the COSMOS database.
Are sulphates safe?
Sulphates may be considered safe (in certain formulations), but that doesn’t mean that they have no damaging effects or that they should be in the products you use. These harsh chemicals are so good at cleaning that they can really dry out your skin and hair, stripping off the natural oils and proteins. Without these substances, your skin and hair lose their first line of defense against disease-causing bacteria and allergens, becoming vulnerable to infection and irritation.
In addition, sulphate shampoos can ruin hair's cuticle, resulting in split ends, dullness, and breakage. Sulphates are anionic surfactants, which means that they leave the hair with a negative electric charge, increasing frizz and friction. When people switch to sulphate free shampoos, their hair gets a break from these damaging effects and suddenly becomes softer and more manageable.
To sum up, sulphate free skincare products are gentler and don't strip away the protective oils on your skin and your hair. They don’t disrupt the delicate balance of proteins and peptides that provide vital protection from microbes and environmental pollution. And they don't leave your hair dry and frizzy.Dry, frizzy hair? Could be too many sulphates in your shampoo!
Alternatives to sulphates
- cocamidopropyl betaine,
- disodium lauroamphodiacetate,
- sodium cocoamphoacetate,
- coco glucoside, and
- lauryl glucoside
Castile soap is a great natural alternative to sulphate soaps and shampoos. This gorgeous multitasking product is made the traditional way from olive oil and other plant oils. Use it on your hair, face, and body, and even on your pets, dishes, laundry, and floors!
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