Highlights
Skim through
| Ingredient name | what-it-does | irr., com. | ID-Rating |
|---|---|---|---|
| Ricinus Communis Seed Oil | emollient, perfuming | 0, 0-1 | |
| Polysorbate 20 | emulsifying, surfactant/cleansing | 0, 0 | |
| DMDM Hydantoin | preservative | icky |
Sondos Castor OilIngredients explained
Castor oil is sourced from the castor bean plant native to tropical areas in Eastern Africa and the Mediterranean Basin. It is an age-old ingredient (it’s over 4,000 years old!) with many uses including as a shoe polish, food additive and motor lubricant. You would be reasonable to think that putting shoe polish on your face wouldn’t be the best idea, but it turns out castor oil has some unique properties that make it a stalwart in thick and gloss-giving formulas (think lipsticks and highlighters).
So what is so special about it? The answer is its main fatty acid, called ricinoleic acid (85-95%). Unlike other fatty acids, ricinoleic acid has an extra water-loving part (aka -OH group) on its fatty chain that gives Castor Oil several unique properties. First, it is thicker than other oils, then its solubility is different (e.g. dissolves in alcohol but not in mineral oil), and it allows all kinds of chemical modifications other oils do not, hence the lots of Castor oil-derived ingredients. It is also more glossy than other oils, in fact, it creates the highest gloss of all natural oils when applied to the skin. Other than that, it is a very effective emollient and occlusive that reduces skin moisture loss so it is quite common in smaller amounts in moisturizers.
While it is very unlikely (and this is true for pretty much every ingredient), cases of reactions to castor oil have been reported, so if your skin is sensitive, it never hurts to patch test.
It's a common little helper ingredient that helps water and oil to mix together. Also, it can help to increase the solubility of some other ingredients in the formula.
A controversial preservative that has formaldehyde-releasing properties. It works great against bacteria and also has mild fungicide abilities.
Cosmetic chemist, Colin wrote a great article about formaldehyde and DMDM Hydantoin. He writes that formaldehyde is the perfect example of "the dose makes the poison" principle. It's a natural stuff that can also be found in fresh fruits and vegetables, and eating it in tiny amounts is totally ok. However, in larger amounts (according to Wikipedia 30 mL of a solution containing 37% formaldehyde) it's deadly.
The amount of formaldehyde used in cosmetics either neat or through formaldehyde-releasing preservatives is tiny. Probably that is why the Cosmetic Ingredient Review Broad concluded both in 1988 and in 2008 that DMDM Hydantoin is "safe as used in cosmetics".
However, Colins argues that in the case of formaldehyde-releasing preservatives, formaldehyde is released slowly and the skin has probably not evolved to deal with that. The lingering formaldehyde might be toxic to the Langerhans Cells that are important for the skin's defense system. Another potential issue is that formaldehyde-releasers might also release other things while reacting with amino acids in the skin that is probably the explanation why some people are not allergic to formaldehyde but are allergic to formaldehyde-releasing preservatives. These are all theories, far from proven facts, but we feel that there are some justified reasons why formaldehyde-releasing preservatives and Dmdm Hydantoin count as controversial.
All in all, it's up to you to decide if you wanna avoid this preservative group or not. If so, there are other, less risky and more skin-friendly options out there.
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| what‑it‑does | emollient | perfuming |
| irritancy, com. | 0, 0-1 |
| what‑it‑does | emulsifying | surfactant/cleansing |
| irritancy, com. | 0, 0 |
| what‑it‑does | preservative |