Testing & Re-testing

After years of working voluntarily with the sunscreen standard, New Zealand has now adopted this standard as mandatory for sunscreens.

We were part of the submission process in support of making this standard mandatory.

There's more work to be done. Testing procedures are refining, working to decrease variability of results between labs. And re-testing protocols are being considered, but not mandated at this time.

With the updated standard ASNZ 2604:2021 expected to be formally adopted, this is an opportunity for all companies to re-test sunscreens from scratch in the next few years.

Issues of Efficacy over Time

We recommend that you keep your sunscreens fresh. Renew your supply each season.

Chemical absorbers are vulnerable to degradation over time, so how a product ages in the tube is really important.

Mineral sunscreen agents like zinc oxide and titanium dioxide don’t degrade over time, but the trick with these ingredients is keeping them smoothly mixed. They are heavy ingredients with a tendency to clump and sink. They also oxidise the other ingredients in the formula when exposed to heat and air. Again, over time, this can mean a change in the performance of the sunscreen.

We agree that re-testing is critical for sunscreens if you change the formula. Small formula changes can have large consequences. It’s also important to re-test batches as they age.

Sun Balm Test Results

Goodbye OUCH Sun Balm was released in 2018, and to give us complete confidence in the product, we tested it through twice at two different performance points. These were completed between May and July 2018. A complete test with 10 people with sunscreen applied and then skin in water for 2 hours and then tested for SPF yielded an average above 50 SPF. A second complete test with a different 10 people had sunscreen applied, with their skin immersed in water for 4 hours. Their average test results yielded  above 40SPF.  

As importantly, and as part of the standard, we tested for critical wavelength, which is the UVA or part of the broad spectrum coverage in a sunscreen. ASNZ 2604: 2012 has the highest requirement for Broad Spectrum coverage in the world. It not only requires that the skin is protected at a certain spectrum of UVA, but that it is balanced to the coverage of the UVB.  Sun Balm passes this critical wavelength and protection factor test.

The lab that we use is Dermatest, a highly regarded leader in the sunscreen testing space.

Beyond the Standard

High compliance and reliability in SPF labelling is a good beginning. An understanding of Broad Spectrum and testing critical wavelength is also key. However, with marine toxicity issues, people toxicity issues, and oxidative stress studies on certain UV absorbing ingredients there's more to be done. The landscape for what makes a good, reliable sunscreen is broader than the standard.