Photostability: LUCA vs. Other SPF 30 Sunscreens

*Critical Wavelength: Critical wavelength is an international rating system for UVA protection. It is a measurement performed on a machine in which sunscreen is applied to a slide. The slide is then irradiated from an artificial light source to simulate sun exposure. Exposure begins at 290nm, with subsequent exposure to progressively higher wavelengths of light. The point at which the sunscreen allows 10% of the rays to penetrate through the slide is defined as the critical wavelength. Another way of looking at this, would be this is the point where the level of protection provided by the sunscreen has dropped, to the point where only 90% of the rays are blocked (absorbed). The advantage of the critical wavelength is that it is an in vitro, very reproducible laboratory test. A sunscreen with a critical wavelength over 370nm is considered by the FDA to provide excellent UVA protection.

Directions: For maximum protection apply generously to skin and re-apply after perspiration or if product is rubbed off. Do not apply product on infants under 6 months of age. Active Ingredients: Avobenzone (3%), Homosolate (7.5%), Octisalate (5%), Octocrylene (2.5%) Warnings: For external use only. Do not ingest. Avoid contact with the eyes. If contact with eyes occurs, rinse eyes thoroughly with water. Discontinue use if irritation or rash appears. If irritation or rash persists, consult a doctor. Do not apply product on infants under 6 months of age. KEEP OUT OF REACH OF CHILDREN.

It's hard to wade through the qualifications of each sunscreen and select the one that delivers maximum protection. I trust the research behind LUCA Sunscreen. It assures me of optimum protection for my family by balancing UVA/UVB protection in a very usable, skin-friendly non-irritating lotion. I use LUCA every day. There is a bottle in my make-up kit and one in my car for my hands. - Chris N., Age 42, Charleston, SC.

The Science of Luca

LUCA™ is the best UVA/UVB sunscreen available in the United States, because our formulations contain Polycrylene®, a novel Avobenzone stabilizer and strengthener. Avobenzone provides great UVA protection, but without the addition of Polycrylene®, it begins to breakdown after 10 minutes in intense sunlight. In addition to excellent UVB coverage rated by familiar SPF ratings, LUCA™ is the only product in the United States to voluntarily place a critical wavelength value (see critical wavelength above) on our label showing our level of UVA protection.

Good daily UVA protection is very important. As a pathologist, I have seen an increase in the numbers of skin carcinomas and melanomas which are diagnosed each year in an ever younger patient population. UVA rays are strongly linked not only to melanoma, but to the aging associated with sun exposure (wrinkles, sun spots, loss of elasticity, skin thinning, etc). Daily UVA/UVB protection is necessary on chronically sun exposed skin surfaces (face, arms, ect.).

The graph above shows the protection with LUCA™ versus a “good” broad spectrum formulation. Notice that both give good UVB protection and both can state UVA/UVB on the label; however LUCA™ gives substantially more UVA protection. The orange area shows the increased protection possible with LUCA™ because it uses Avobenzone which has been stabilized and strengthened by Polycrylene®. This increased UVA protection is reflected in our critical wavelength, which is the highest in the U.S. market. Critical wavelength is an internationally recognized rating system for UVA protection which will likely be adopted by the FDA at some point in the future.

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