SPF Testing and Photobiology
In Vivo and In Vitro Methods to Document Your Efficacy
Validated Claim Support custom developed its SPF testing department based on the current needs of the industry: high volume static and Water Resistant output based on the various international standards.
Sun Protection Factor (SPF) Explained
SPF is a highly regulated and sought-after claim in the industry that represents a relative added protection factor offered by a consumer grade, OTC product against the UV radiation emitted from the sun.
As defined by Cancer.gov and the Center for Disease Control (CDC) the different UV radiation components are as follows:
Invisible rays that are part of the energy that comes from the sun. Skin specialists recommend that people use sunscreens that protect the skin from ultraviolet radiation. In medicine, ultraviolet A radiation also comes from special lamps or a laser and is used to treat certain skin conditions such as psoriasis, vitiligo, and skin tumors of cutaneous T-cell lymphoma.
UVB represents one of the most energetic wavelengths emitted from the sun, and is historically the main cause of reddening and inflammation after sun exposure.
Ultraviolet B radiation causes sunburn, darkening and thickening of the outer layer of the skin, and melanoma and other types of skin cancer. It may also cause problems with the eyes and the immune system. Also called UVB radiation.
UVB is the only wavelength that is tested for in the traditional SPF in vivo analysis, and is determined with a comparison of treated skin to untreated skin with a controlled dose of radiation. The MED or Minimum Erythemal Dose as graded by a trained technician and the time it takes to become visible represents the SPF rating.
UVA is the most prevalent form of radiation that is not absorbed by the Earth’s ozone layer and magnetic field.
Ultraviolet A radiation also comes from sun lamps and tanning beds. Ultraviolet A radiation may cause premature aging of the skin and skin cancer. It may also cause problems with the eyes and the immune system. Skin specialists recommend that people use sunscreens that protect the skin from ultraviolet radiation.
Although though UVA radiation is weaker than UVB, it penetrates deeper into the skin and is more constant throughout the year.
UVC radiation is the highest energy portion of the UV radiation spectrum that is ejected from the sun. WhileUVC radiation from the sun does not reach the earth’s surface because it is blocked by the ozone layer in the atmosphere, that doesn’t necessarily make it any less dangerous.
We are still learning about the long term effects of UVC exposure, and there is not a lot of documented research about how much makes it through the atmosphere. Additionally, there is little to no documented research about what products protect against UVC, and it is not tested for in any traditional SPF in vivo tests supported around the world.
Secondary tanning sources such as indoor beds/lamps and medical devices are a likely high risk factor for UVC transmission.
UV Testing Standards Supported
VCS is compliant with all major international standards including:
- FDA Static, 40 and 80 min Water Resistant
- ISO 24442, 24443, 24444
- Colipa Water Resistant and Very Water Resistant
- Australia/New Zealand
- JCIA UVA
Custom Protocol are available to test conditions such as:
- Chlorinated Water
- Salt Water
- Sand Resistance
- Towel/Abrasion Resistance
- Wet Application
Please note that the secondary claims noted above may or may not be approved by regulatory bodies throughout the world. Always consult your legal team when developing your claims.
In Vitro Claims (UVA and Broad Spectrum)
VCS maintains a variety of UV analyzers at the in vitro level, and can help to support Broad Spectrum and UVA claims as well.
By measuring the absorption and transmittance of UV radiation through a PMMA or glass substrate with product applied, it is possible to determine the UVA passthrough and thus the protection offered by individual products.
In vitro claim support can also help to provide some comparative data at the SPF/UVB level prior to engaging in in vivo testing, although it is important to note that In Vitro UV data is not recognized by any international regulatory authorities at this time.
VCS maintains a custom developed spa/water resistance lab with 8 individual treatment tubs. All tubs have been customized with in line continuous heating and water flow parameters traceable to international standards.
All 8 VCS tubs are single capacity to ensure accuracy and hygiene throughout the testing process.
Onsite SPF and UVA training conducted by Dr. Curt Cole (President, Sun and Skin Consulting) and Solar Light Company, America’s premier manufacturer of Precision Lightsources and the inventor of the first Solar Simulator in 1967.
Solar Simulators and detectors are calibrated annually to NIST traceable standards via Solar Light and/or Rapid precision Testing Laboratories.
VCS Maintains Multiport and Single port simulators as per client requirements and specifications.
A method designed to determine the UV degradation/alteration of a given product when applied to the skin. Phototoxicity presents a serious concern when products are designed to be warn in just about any climate throughout the world. Pairs immediate irritation testing (24/48 hour patch) with UV exposures.
For products that are designed for long term or pediatric use, it is imperative to determine that products don’t break down and cause irritation after continued exposure to the sun or secondary UV radiation.
Pricing varies based on bulk submissions:
A more involved method which effectively pairs continuous application, repeat insult patch testing and multiple UV exposures. Photo-Allergy Maximization is more robust than Phototoxicity and incorporates sensitization/allergenic potential as well as UV exposures.
This provides a measure of the most demanding aspects of both Repeat Insult Patch Testing along with a continuous UV exposure to simulate the effect of the sun on a product over time.
As per CDC Guidelines, SPF is Not Necessarily Enough
- Stay in the shade, especially during midday hours.
- Wear clothes that cover your arms and legs.
- Consider options to protect your children.
- Wear a wide brim hat to shade your face, head, ears, and neck.
- Wear wraparound sunglasses that block both UVA and UVB rays.
- Use sunscreen with sun protection factor (SPF) 15 or higher, for both UVA and UVB protection.
- Avoid Indoor Tanning. Indoor tanning is particularly dangerous for younger users; people who begin indoor tanning during adolescence or early adulthood have a higher risk of developing melanoma.