Does Thieves Hand Soap cause cancer?

Q. Does Thieves Hand Soap Cause Cancer?

A. From Lindsey Elmore:
My inbox has been inundated with people scared that their favorite hand soap may cause cancer they cite the Environmental Working Group for rating retinyl palmitate (RP) as a 9/10 for carcinogenicity.

RP is an ester of Vitamin A, and it is converted to retinol and then to retinoic acid (RA). RA is responsible for supporting the appearance of skin, but is also highly irritating to skin. RP is commonly included in moisturizers and soaps because it is so much more gentle on the skin than retinol or RA, and it is very shelf-stable.🧴

There is concern that RP increases the risk of skin cancers and reproductive and developmental toxicities.

There is not human data to suggest that RP causes skin cancer, only animal data. In one study, hairless mice were exposed to cream containing RP, and then exposed to UV lights. The mice treated with RP had an increased risk of skin cancer. However, the legitimacy of this data has been questioned because mice used were genetically predisposed to skin cancers. Another study found an increased risk of skin lesions following application of 1% RP and exposure to UVB light, but so did the control group. UVA, not UVB, is the most common cause of skin cancer. In this study, using RP actually reduced the occurrence of skin lesions following exposure to UVA.

The reproductive and developmental toxicity data is also not great. In many studies RP was combined with methylmercury (MM). We have data to suggest that RP causes pro-oxidation in reproductive tissues, but only when combined with MM. When RP is supplemented in the diet without MM, broiler chickens actually have improved reproductive function.

Bottom line. It is easy to sensationalize data. Be real. For skin cancer, avoid UV light. For reproductive toxicity, avoid mercury.

Don’t believe everything that you read, interpret data carefully. When you don’t know how, send it my way. I’ll put it in perspective.