Sodium Hydroxide

The Basics On Sodium Hydroxide

What is Sodium Hydroxide?

Also known as lye, it is a highly alkaline ingredient used in small amounts in cosmetics.

What are other names for Sodium Hydroxide?

CAUSTIC SODA, CAUSTIC SODA; SODIUM HYDROXIDE; SODIUM HYDROXIDE, SODIUM HYDRATE, SODIUM HYDROXIDE, SODIUM HYDROXIDE (NA(OH)), and SODIUM HYDROXIDE SOLUTION

What is Sodium Hydroxide used for?

Also known as lye, sodium hydroxide is a highly alkaline ingredient used in small amounts in cosmetics to establish and hold the pH of a product. It’s also used as a cleansing and denaturing agent. In high concentrations, it’s a significant skin sensitizer.

How Sodium Hydroxide is classified

Cleansing Agents, Sensitizing

Recommendations for using Sodium Hydroxide during pregnancy and breastfeeding

Limited data suggests no known risk

 

Sodium Hydroxide During Pregnancy

What we know about using Sodium Hydroxide while pregnant or breastfeeding

Limited information available.

Magnesium Hydroxide The reproductive toxicity of magnesium hydroxide (pH = 10) was studied in rats that received the test material via gavage. 9 The study followed OECD guideline 422. Groups of 10 male and 10 female Wistar rats received 0, 110, 330, or 1000 mg/kg bw/day magnesium hydroxide in water daily. Males were exposed for 29 days (i.e., 2 weeks prior to mating, during mating, and up until treatment end) and females were exposed for 41-45 days (i.e., 2 weeks prior to mating, during mating, during gestation, and during at least 4 days of lactation). No treatmentrelated effects were observed on clinical signs, body weight or weight gain, feed consumption, or hematology. In parental males, lower total protein levels (330 and 1000 mg/kg dose groups), lower albumin levels (1000 mg/kg dose group), and lower calcium levels (330 and 1000 mg/kg dose groups) in the blood, and lower sodium and potassium excretion (1000 mg/kg dose group) and higher calcium concentration in urine (1000 mg/kg dose group) were observed; however, these changes only just exceeded or remained within normal ranges and there were no corresponding histopathological changes. No toxicologically relevant changes from the test material were observed in parental organ weights or in gross pathology. There were no treatment-related effects on offspring development. The no observed adverse effect level (NOAEL) for parental systemic effects, parental reproductive effects, and offspring effects in this one generation rat study of magnesium hydroxide was 1000 mg/kg bw/day.

General safety info about Sodium Hydroxide from CIR

The Cosmetic Ingredient Review (CIR) Expert Panel reviewed the safety of inorganic hydroxides, which function in cosmetics primarily as pH adjusters. Industry has indicated these ingredients are used in depilating and hair waving/straightening formulations to raise pH values. The Panel considered relevant data related to these ingredients. The Panel concluded that these inorganic hydroxides are safe in hair straighteners and depilatories under conditions of recommended use; users should minimize skin contact. These ingredients are safe for all other present practices of use and concentration described in this safety assessment when formulated to be nonirritating.

Use this, not that!

Products where you might find Sodium Hydroxide

Drunk Elephant B-Hydra Intensive Hydration Serum; Drunk Elephant Lala Retro Whipped Moisturizer with Ceramides; The Ordinary Natural Moisturizing Factors + HA