Guide to Selecting the Right SPF Testing Lab

You’ve developed a sunscreen that you’re excited to launch, but still need to find a SPF testing lab to meet your needs — what is it that you should look for?

Although you may consider factors such as budget and time-to-launch, you also need to think about your long-term goals. It is in your best interest to use a laboratory that is up-to-date with methods, training and equipment; a laboratory which will conduct testing that is scientifically sound, compliant and stands-up to FDA scrutiny. The ethics of any organization you do business with is important, but it is essential in a testing laboratory.  When visiting or auditing your laboratory, you should be allowed complete access to your study, the area in which testing is conducted, the equipment that is used, and all testing and equipment calibration records.  If you’re preparing to launch a product that makes claims regarding the Sunscreen Protection Factor (SPF) value, here’s what you need to know.

What is SPF Testing?

A sunscreen product’s SPF value will be based on the amount of time or energy, that it takes for one’s skin to redden when exposed to UV radiation, whilst protected by a sunscreen product vs. no protection. Basically, if a product has an SPF of 30, this means that if it takes 10 minutes for unprotected skin to experience redness, it will take 30 times that, or 300 minutes to redden, when wearing the SPF 30 product as directed.

Calculations made from clinical trial data will determine the SPF  of your product. It is upon this calculated SPF that you can base your labeling claims.

In the early 1990s, “in-vitro” testing was developed to evaluate UVA protection.  Ultraviolet-A is known to cause tanning, skin cancer, and premature skin aging in the long-term. Based on the guidelines set by the FDA, an in-vitro critical wavelength method is suitable for measuring a product’s Broad Spectrum Protection.

How to Find the Right SPF Testing Lab

If you’re planning on launching a  new sunscreen product, you’ll require a lab that can efficiently and ethically perform all related SPF tests. These required tests are  based on specific guidelines, which include, but are not limited to:

• FDA Final Rule — As of June 2011, OTC (over-the-counter) sunscreen products must undergo specific labeling and effectiveness tests. This method continues today as the Final Administrative Order (OTC000006) Over-the-Counter Monograph M020: Sunscreen Drug Products for Over-the-Counter Human Use. This includes products that contain specific “allowed” active ingredients, such as avobenzone, meradimate, octocrylene, padimate and others.
• ISO 24444 — Now adopted in nearly 60 countries, supportable claims include SPF number and sunscreen efficacy. This excludes the USA but includes countries such as Australia, Canada, China, Chile, New Zealand, India, Russia and various other global countries.
• ISO 24442 — In compliance with EU requirements, this method focuses on UVAPF — Ultraviolet A Protection Factor. UVA has been linked to photoaging and skin cancer. When a product protects against both UVA and UVB radiation, this qualifies as a Broad Spectrum product.

In addition to SPF efficacy, you may also want to test for Water Resistance and in-vitro Broad Spectrum Efficacy, depending on the claims you wish to make:

• Water Resistance Efficacy — To make this claim, a water-resistance test must be performed. This will demonstrate that a product’s SPF protection is retained for 40 to 80 minutes after being immersed in water.
• In-vitro Broad Spectrum Efficacy — This measures a product’s absorbance of UV radiation across both the UVB and UVA spectrum.

When testing sunscreen products, clinical and non-clinical laboratories  employ:

• Single-port solar simulators, and
• Multi-port solar simulators

Solar simulators create artificial sunlight, which provide UV illumination that mimics natural sunlight. The purpose of this equipment is to provide a controlled and uniform UV exposure under which your sunscreen product will be tested.  All solar simulators must be evaluated on a regular basis to ensure that their UV output is consistent with applicable regulations.

Although the process may differ slightly based on your objectives and claims, before you launch, you should follow the basic steps as outlined below:

1. Identify where you will be selling your product, as markets differ. For example, test requirements will differ between the USA and Australia.
2. Determine the SPF value of your product based on your intended claim.
3. When claiming Water Resistance, this will typically be based on 40- or 80-minute protection.
4. Next, you’ll want to consider Broad-Spectrum claim requirements. In most markets, an in-vitro test is acceptable. Once again, FDA requirements differ in comparison to ISO.
5. For sunscreen products sold within the US, you are required to determine the expiration date of the product in each of its marketed container systems prior to launch.
6. As a recommendation, the earlier you include a testing laboratory in your planning, the less likely there will be problems in meeting your launch date.

Questions to Ask An SPF Testing Lab

When you’re in the market for an SPF testing lab, you’ll want to do your homework. Depending on the claims you’d like to make, and the jurisdiction in which you plan to launch your product,  different testing procedures and recognized protocols will be required.

Some of the main questions you’ll want to ask the SPF testing lab include:

• Can you perform SPF testing according to all methods worldwide, in-vivo and in-vitro?
• Can you combine test protocols based on my target markets?
• Do you offer Analytical and Microbiological testing services in support of stability studies for determining expiration date prior to launch?
• What type of equipment do you operate within your lab and what are the critical elements of the Equipment Calibration Program that you have in place?
• How will your laboratory ensure truthful, impartial and accurate test results?
• Do you comply with ALCOA+ Data Integrity requirements?
• Can I monitor my study at any time? Can I audit the facility and Quality System?
• What regulations does the lab comply with? Can I review the results of recent regulatory inspections?

Don’t be shy about asking tough questions. Request a tour of the testing facility and an equipment list. The future success of your product will be determined by these extremely critical initial tests. You cannot entrust your SPF testing to a laboratory that is unethical or fails to meet current FDA requirements for GMP/GCP testing laboratories. FDA has recently invalidated SPF test results that have been generated by an unethical SPF testing lab, and other labs which fail to meet the basic requirements of GMP/GCP and Data Integrity. Plan wisely and conduct due diligence when selecting a testing laboratory.  The success of your product may depend upon it.