Is It Safe to Make Soap at Home?

people making soap at home

The Bottom Line

Soapmaking is a popular home activity, but potentially hazardous chemicals are often involved. Use of pre-made soap bases, or “melt and pour” products, is a safer way to make homemade soap.

mother and daughter making soap

The Full Story

According to one Roman legend, the first soaps were accidentally discovered around 3000 years ago on Mount Sapo, near Rome. After animals were sacrificed on a mountain temple to please the Roman gods, the leftover animals’ fatty tissues, mixed with ashes of altar fires, ran downhill over the mountain. Women who visited the temple noted that the mixture of animal fat and ashes helped to wash and clean their clothes when mixed with rainwater. Since then, various mixtures of fats and ashes have been incorporated into soaps, and the concept of combining fats and ashes remains an important part of soapmaking in modern times.

Ashes are alkaline, which means that they have a high pH. When alkaline products are combined with fats, a chemical reaction called saponification occurs. The process of saponification results in the formation of fatty acid salts, otherwise known as soap. The alkaline product is ideally incorporated entirely into the saponification process, so there is no residual alkali left over in the finished soap product. Today, many soaps are made using a saponification process that incorporates lye (an alkaline chemical) and oil (a fat product). Commercially manufactured soaps often contain other ingredients including surfactants, plasticizers or binders, lather enhancers, and fragrance. Homemade soaps can be created with much simpler ingredients including lye, oil, water, and (if desired) essential oils to add fragrance. The art of crafting homemade soap is increasing in popularity, and there are many instructional tutorials on making soap that are available on TikTok, YouTube, and other social media and online platforms. Many of these videos depict the soapmaking process as being deceptively easy…mix the chemicals together, add in some fragrance, and pour the mixture into a silicone mold to harden. Despite the relatively simple recipes, however, it’s important to know that the chemicals used in the soap-making process can be potentially dangerous.

Lye, also known as caustic soda or sodium hydroxide, has a very high pH and is known as a strongly basic chemical. Lye is a common ingredient in drain cleaners and is also present in some toilet bowl cleaning products. When human skin, eyes, or other tissues come into contact with lye, significant injuries can occur including skin irritation, chemical burns, and blindness. Even though lye is odorless, irritation of the nose and throat can occur in individuals who breathe in lye mist or aerosols. Lye is also potentially flammable, as it produces heat when dissolved in water. Although some social media videos depict people mixing soap-making ingredients without the use of gloves, this is not recommended due to the highly irritating and corrosive properties of lye. In addition, lye should only be used in a well-ventilated area. Children are highly susceptible to the toxic effects of lye and should never be allowed to handle lye or come into close contact with it. People who get lye in their eyes or on the skin should wash the affected area(s) immediately with room-temperature water for at least 15-20 minutes. For skin exposures to lye, gentle washing of affected areas with room-temperature water is recommended.

Essential oils are another common ingredient used in homemade soap. Essential oils are derived from the essence, or aromatic components, of plants. These oils can be used to provide fragrances for homemade soaps. Even though many essential oils have a very pleasant smell, they can be poisonous when swallowed, inhaled, or applied to the skin. When swallowed, many essential oils may cause stomach irritation, nausea, or vomiting. However, some essential oils, including clove oil and lavender oil, can be much more poisonous when consumed. Even accidental ingestion of very small amounts of these oils can result in drowsiness, coma, and seizures. Since children often do not realize that essential oils don’t taste as good as they smell, ingestions of essential oils are common in toddlers and younger children and may be associated with severe toxicity. For this reason, it is very important to keep all essential oils well out of the reach of young children, including when making homemade soap. In addition, while many people enjoy diffusing essential oils and inhaling their fragrance, some essential oils can be dangerous when high concentrations are inhaled. For example, inhalation of high concentrations of peppermint oil can cause seizures and even death. Since people with asthma or underlying lung disease can experience difficulties in breathing, coughing, or other respiratory symptoms after inhaling essential oil fragrances, essential oils should be used with caution by individuals with respiratory problems. The application of essential oils to the skin can also lead to harmful effects for some people. Skin irritation, including allergic contact dermatitis, can occur after topical application of essential oils to the skin. Individuals who have sensitive skin, including children, should not apply essential oils to their skin or use these products when making homemade soaps.

Fortunately, there is a way to create homemade soap while avoiding exposure to these potentially harmful chemicals. Pre-made soap bases (also known as “melt and pour” products) are available for purchase online and at craft stores. These products have already undergone saponification, so there is no need to add lye. The pre-made soap bases can be melted, infused with dyes or fragrances if desired, and poured into molds to create soap. The use of pre-made soap bases is a safer method of making homemade soap, as it does not involve the use of lye.

If you develop concerning reactions after exposure to essential oils or lye, Poison Control is available to help. There are two ways to contact poison control: go online to www.poison.org or call 1-800-222-1222. Both options are free to the public, confidential, and available 24 hours a day.


Kelly Johnson-Arbor, MD
Medical Toxicologist

Poisoned?

Call 1-800-222-1222 or

HELP ME online

Prevention Tips

  • When using lye, always wear personal protective equipment, including masks, goggles, and gloves.
  • Use pre-made soap bases (“melt-and-pour” products) as a safer option when making soap with children.
  • Always make soap in a well-ventilated area.

This Really Happened

In 2020, six brands of sodium hydroxide and potassium hydroxide were recalled by their manufacturer due to a lack of child-resistant packaging. The recalled products were packaged in clear plastic bottles with caps and were sold for the purposes of home soapmaking as well as drain cleaning. The United States Consumer Product Safety Commission received two reports of chemical burn injuries that occurred after use of the products. In one case, a child developed chemical burns on the mouth after exposure to one of the products.

For More Information

How to Make Homemade Soap, Even If You're a Beginner (Good Housekeeping)

Sodium Hyrdoxide (Agency for Toxic Substances and Disease Registry)


References

Friedman M, Wolf R. Chemistry of soaps and detergents: various types of commercial products and their ingredients. Clin Dermatol. 1996 Jan-Feb;14(1):7-13. 

Prieto Vidal N, Adeseun Adigun O, Pham TH, Mumtaz A, Manful C, Callahan G, Stewart P, Keough D, Thomas RH. The Effects of Cold Saponification on the Unsaponified Fatty Acid Composition and Sensory Perception of Commercial Natural Herbal Soaps. Molecules. 2018 Sep 14;23(9):2356. 

Routh HB, Bhowmik KR, Parish LC, Witkowski JA. Soaps: from the Phoenicians to the 20th century--a historical review. Clin Dermatol. 1996 Jan-Feb;14(1):3-6.

United States Consumer Product Safety Commission. Boyer Recalls Six Brands of Sodium and Potassium Hydroxide Due to Failure to Meet Child-Resistant Packaging Requirement; Injuries Reported. Accessed 5.12.22.

Wolf R, Wolf D, Tüzün B, Tüzün Y. Soaps, shampoos, and detergents. Clin Dermatol. 2001 Jul-Aug;19(4):393-7. 

Poisoned?

Call 1-800-222-1222 or

HELP ME online

Prevention Tips

  • When using lye, always wear personal protective equipment, including masks, goggles, and gloves.
  • Use pre-made soap bases (“melt-and-pour” products) as a safer option when making soap with children.
  • Always make soap in a well-ventilated area.

This Really Happened

In 2020, six brands of sodium hydroxide and potassium hydroxide were recalled by their manufacturer due to a lack of child-resistant packaging. The recalled products were packaged in clear plastic bottles with caps and were sold for the purposes of home soapmaking as well as drain cleaning. The United States Consumer Product Safety Commission received two reports of chemical burn injuries that occurred after use of the products. In one case, a child developed chemical burns on the mouth after exposure to one of the products.