We’re not mice, but sun-worshippers take note: a study done on mice show some skin cream ingredients are tied to an increase in skin tumors, especially for those previously over-exposed to the sun.

A study recently reported in the August 14th, 2008 online publication of Journal of Investigative Dermatology linked use of certain skin creams with an increased development of tumors in “high-risk” mice.

They made these hairless mice high-risk for tumor development by irradiating them with UVB rays two times a week for 20 weeks. After this period of time they were considered high-risk for the next several months even though they received no further UVB exposure.

After this UVB exposure, several skin creams (or skin cream bases) were applied to their skin: Dermabase, Dermovan, Eucerin Original Moisturizing Cream, or Vanicream. The creams were applied once a day, 5 days a week for a total of 17 weeks.

Results showed several findings: After using these creams on (high-risk-for-skin-tumor) mice, there was a significant increase in the rate of tumor formation, the size of the tumors and total number of tumors.

Dr. Alan Conney, who let the study, said “We don’t know what happens in humans, but this is a red light saying there should be some epidemiological study in human populations.”

Apparently, mice skin is thinner and more permeable than human skin, but Conney said the study “is similar to humans who may be exposed early in life to a lot of sunlight, then not as much later in life, but still come down with skin cancers.”

Conney said, “There was no common ingredient” in the moisturizers that they determined caused these results. “It has to involve the combination of ingredients,” said Conney.

The manufacturers of the various creams refuted this study, citing many years of use and also recommendations by dermatologists.

On the surface, even if this study is accurate, it doesn’t seem to help the consumer much. How can we know what skin cream ingredients are safe and which ones may promote skin cancer if the study doesn’t show that?

Other studies on skin care ingredients show many are suspected of causing health and skin problems including cancer. Here is one list of suspects from www.ChaeOrganics.biz.

Red Flag Ingredients (toxic synthetic chemicals) to Avoid:
• Alcohol, Isopropyl (SD-40)
• Benzoyl Peroxide – found in many acne products
• DEA (Diethanolamine), MEA (Monoethanolamine), & TEA (Triethanolamine)
• Dioxin – extremely toxic, by-product of manufacturing Tirclosan, etc.
• DMDM Hydantoin & Urea (Imidazolidinyl)
• FD&C Color and Pigments
• Fragrances – a term for all synthetics
• Parabens - Methyl, Propyl, Ethyl, Butyl
• PEG (Polyethylene glycol) with any number or addition
• Phthalates - (often present with sunscreens and other ingredients on this list)
• Propylene Glycol (PG) and Butylene Glycol
• Quaternium 15
• Sodium Lauryl Sulfate (SLS), Sodium Laureth Sulfate (SLES), Sodium Methyl Sulfate
• Sunscreen chemicals: avobenzone, benzphenone, methoxycinnamate, paba, etc.
• Triclosan – antibacterial agent

I believe the best thing we can do is educate ourselves on the latest findings, avoid toxic and synthetic chemicals, and search for skin care products that have as many organic, natural, and vegetable-based ingredients as possible.