What Is Zinc Ricinoleate?

This is part of our ongoing series to help consumers better understand chemicals, chemistry, and product formulations. We translate the science, bust the myths, and give you an honest assessment, so you can make informed choices for your family!

Ingredient:

Zinc Ricinoleate

What it is:

Zinc ricinoleate is the zinc salt of ricinoleic acid, a major fatty acid found in castor seed oil obtained from the seeds of the Ricinus communis plant.

What it does:

This interesting little ingredient traps and absorbs odor molecules, making them imperceptible to the odor receptors in your nose. Simply put: it deodorizes!

Why we use it:

As much as we love using ingredients that come from nature, they have to be safe and effective, too. Lucky for us, zinc ricinoleate fits the bill. It’s most commonly used in natural underarm deodorants, but it works perfectly as an Air + Fabric Freshener, so why hide it? It’s also a better alternative to the toxic chemicals and masking agents used in conventional air fresheners.

Why we’re featuring it today:

“Natural” doesn’t always mean “safe”: Castor seeds are the perfect example. Hiding inside the castor seed is a highly toxic protein called ricin that’s so toxic just a few purified grains the size of table salt can kill an adult. Some people wonder if castor oil and its derivatives (like zinc ricinoleate) could be contaminated with ricin. The answer is a resounding no. Ricin is a water soluble compound, so it can’t bind to the oil. On the chance that there should be a stray molecule, manufacturing castor oil involves a heating process that neutralizes and effectively deactivates the protein. Castor oil has been safely used for many applications, from cosmetic to medicinal, for thousands of years. There’s no need to worry about ricin in our zinc ricinoleate!

Have any other questions about zinc ricinoleate? Let us know in the comments! We’re always happy to help!

References:

• Bohmer, T., Muller, F., & Peggau, J. (2003). New results on odor absorption with zinc ricinoleate. JORNADAS-COMITE ESPANOL DE LA DETERGENCIA,33, 143-154.
• Final Report on the Safety Assessment of Ricinus Communis (Castor) Seed Oil, Hydrogenated Castor Oil, Glyceryl Ricinoleate, Glyceryl Ricinoleate SE, Ricinoleic Acid, Potassium Ricinoleate, Sodium Ricinoleate, Zinc Ricinoleate, Cetyl Ricinoleate, Ethyl Ricinoleate, Glycol Ricinoleate, Isopropyl Ricinoleate, Methyl Ricinoleate, and Octyldodecyl Ricinoleate. (2007, 12). International Journal of Toxicology,26, 31-77. doi: 10.1080/10915810701663150
• Kuhn, H.; F. Müller; J. Peggau; R. Zekorn (April 18, 2000). "Mechanism of the odor-adsorption effect of zinc ricinoleate. A molecular dynamics computer simulation". Journal of Surfactants and Detergents (Springer Berlin/Heidelberg) 3: 335–343. doi:10.1007/s11743-000-0137-9.ISSN1097-3958

Zekorn, R. (1997). Zinc ricinoleate: The basis of its deodorizing activity.Cosmetics and toiletries, 112(11), 37-40.