Assessing Sunscreen: Our Testing Methodologies Revealed
Slathering on the Truth: Unraveling the Sunscreen Mystery
Sunscreen, a vital ally in our daily skincare routine, promises to shield us from the sun's harmful rays. But with the plethora of brands and options clamoring for attention, making a well-informed decision can be as torturous as a long day at the beach.
We decided to delve into the issue, aiming to reveal if sunscreens really live up to their Sun Protection Factor (SPF) claims. Our aim: to help Australians make smarter choices when selecting their sunscreen armor.
This write-up provides a breakdown of our testing process, the sunscreens that made the cut, and the factors influencing the variable results often encountered in such tests.
Sunscreen Duke-Out: Syndey Showdown
While we boast a state-of-the-art testing facility, we sent 20 sunscreens to an accredited external laboratory in Sydney for thorough testing. Equipped with specialized expertise and equipment to test sunscreens in accordance with the Australian/New Zealand Sunscreen Standard, as mandated by the Therapeutic Goods Administration (TGA), this lab helped us pinpoint the sunscreens that will protect you best on your sun-kissed adventures.
When one sunscreen returned an extraordinarily low SPF (4), we reconvened in Germany with another accredited lab to retest the questionable product.
Sunscreen Selections: Narrowing Down the Choices
Though testing every sunscreen on the market would be ideal, we narrowed our selection to ensure a fair and relatable test. Utilizing retail data, consumer trends, and expert insights, we selected popular and widely-available sunscreens that cater to various demographics. Our list included a range of price points, chemicals versus minerals, and sunscreens marketed as kid-friendly.
These choices were carefully purchased by our team, ensuring we tested the identical products available to Australians in stores and online. We also ensured the sunscreens had similar expiration dates to guarantee the most accurate results.
The SPF Gauntlet: The Ultimate Test
SPF testing aims to assess manufacturers' compliance with their SPF claims as stipulated by the Australian/New Zealand Sunscreen Standard, aligning with the International Standards (ISO 24444:2019, and 24443:2021).
Each sunscreen initially faced a five-person panel test in the Australian laboratory, followed by further tests for the majority of products (18 out of 20, excluding the La Roche-Posay and Neutrogena products). The sunscreen sent to Germany underwent an additional round of testing on a fresh five-person panel.
Employing the same process manufacturers use to test their products, we carried out blind testing to mitigate bias. We were advised by the laboratory and top experts in the field to ensure the validity of our results and upheld utmost importance for our commitment to independence and scientific integrity.
Panel members were chosen based on their burn-prone skin types and absence of sensitivities to the tested products' components.
Testing 1-2-3: From Application to Results
1. Product Application
An accurate measurement of 2 milligrams of sunscreen per centimeter square of skin is applied to a marked-out skin area. This measurement represents the amount recommended for daily use. The product is evenly spread using a standardized technique and allowed to dry for 15 to 30 minutes.
2. Solar Simulation
A calibrated solar simulator that simulates sunlight is used to apply small, incremental doses of light to the area protected by the tested sunscreen, a control sunscreen, and an unprotected area. After overnight exposure, slight sunburn develops in test areas.
3. Reading of Results
Approximately 24 hours post-exposure, the results are recorded. The lab identifies the exposure time needed for a sunburn to occur without sunscreen, in contrast to the time needed while the sunscreen test sample is applied. The factor between the two represents the sun protection factor (SPF). A control sunscreen is used on each test subject to validate the results.
Fluctuating Fortunes: The Factor of Variability
Differences in SPF test results among labs are often unavoidable, with various factors contributing to inconsistencies.
1. Human Subject Testing and Subjectivity
Since SPF testing relies on human subjects, individual differences in skin type, sensitivity, and application methods can result in inconsistent results across labs. The reliance on subjective human reactions introduces variability.
2. Differences in Testing Protocols and Conditions
While there are standardized guidelines for SPF testing, slight variations in laboratory practices, equipment, environmental conditions, and interpretation of results contribute to inconsistencies.
3. Natural Fluctuation and Margin Around SPF Claims
Due to natural variability, sunscreens boasting an SPF 50+ may test at values below or above the claim, such as within the range of 40 to 72 in different lab tests. Some products tested by Choice fell below the advertised SPF 50 but still provided high protection around SPF 30 while others exceeded the advertised claims.
4. Testing Repetition and Sample Variations
Differences in batches of sunscreen, inconsistent application in tests, and repeated testing cycles contribute to inaccuracies in SPF test results.
In conclusion, SPF test results may differ among labs due to the use of human subjects, varying testing protocols, natural fluctuations, and sample variations.
- In the quest to provide unbiased and reliable product reviews, our testing process for sunscreens involves sending samples to accredited laboratories for thorough analysis, such as the one in Sydney, adhering to the Australian/New Zealand Sunscreen Standard.
- Recognizing the role of privacy in responsible health and wellness reporting, we ensure that our testing methods and results are kept confidential, protecting the data of consumer products and the individuals involved in our tests.
- To cater to the diverse needs of various medical-conditions, skin-care routines, and consumer preferences, we choose a range of popular sunscreens available in stores and online, covering different price points, chemical versus mineral formulations, and sunscreens marketed as kid-friendly.
