SUN JELLY 50 SPF and UVA and critical wavelength tests
Preamble
Measurements were carried out between 4/17/2025 and 4/17/2025 in Helioscience laboratory, under the direction of Jean-Claude HUBAUD, Doctor of Sciences and specialized in solar expertise.
This report is the exclusive property of the study sponsor and may not be communicated to third parties without the latter's written permission.
The people to whom these results were communicated for the purposes of this study have been informed of their confidential nature and have undertaken not to disclose them.
Helioscience – Cité de la Cosmétique – 2 Rue Odette Jasse 13015 Marseille – France
Tel : +33 (0)6 84 80 70 49 – Mail : contact@helioscience.fr 1/10
SUMMARY
1. QUALITY ASSURANCE
2. INVESTIGATOR’S DIPLOMA
3. METHOD PRINCIPLE
3.1. Study purpose
3.2. Method principle
4. OPERATING CONDITIONS FOR CARRYINGOUT THE STUDY
4.1. Materials and methods
4.1.1. Laboratorymaterials
4.1.2. Application support
4.2. Product tested
4.2.1. Sample reception
4.2.2. Productstorage
4.2.3. Deposit 4.2.4. Spreading
4.2.5. Sample selection
4.2.6. Irradiation
4.2.7. Calibration
4.3. Calculation methods
4.3.1. SPF determination
4.3.2. PFUVA determination
4.3.3. CW determination
4.3.4. Standard deviation determination
4.4. Statistical expression of results
5. RESULTS AND CONCLUSIONS
5.1. Results
5.2. Observations on the product and measures
6. CONFIDENTIALITY
6.1. Final report
6.2. Confidentiality and data storage
1. QUALITY ASSURANCE
Jean-Claude HUBAUD certifies that a control has been realized at each step of the following procedure in order to carry out the investigations and the evaluation of the product’s protection concerned and to ensure the reliability of the data analyzed in accordance with this standard procedure.
This report constitutes a precise description of the implementation of the tests, the data processing and the operating resources implemented.
Jean Claude HUBAUD
Scientific direction
2. INVESTIGATOR’S DIPLOMA
3. METHOD PRINCIPLE
3.1. Study purpose
The present study consists in assessing the level of protection level of a cosmetic product containing sun filters by an in vitro spectrophotometric method.
The study is based on ISO 24443: 2021 principles adapted for the sun protection factor "SPF", the UVA protection factor "PF-UVA", and the critical wavelength "CW" determination.
3.2. Method principle
To determine the effectiveness of sunscreens, we evaluate their ability to prevent erythema that appears on the skin's surface if the skin is exposed for a certain time to a source of UV energy. UVB rays represent only about 5% of the total energy received from UV rays (UVA + UVB), but given their energy, they have a major effect on the appearance of this erythema. UVA rays are responsible for around 16% of the onset of sunburn.
The method used consists in measuring the flux of UV energy passing through the cream, expressed in energy transmission, and in comparing this flux with the initial flux according to the principle of any spectrophotometric method:
However, the comparison of these two curves is not sufficient to express the level of protection of the product spread on the skin. Indeed, two other wave functions come into play:
- The source wave function: This is the sun whose spectrum has been defined by the International Commission of Lighting as a S (λ) wave function.
- The wave function concerning the skin: Skin or subcutaneous reactions depend on the energy of the exciting light and are expressed as an E (λ) wave function.
By integrating each of these 3 curves over the entire UVB and UVA range and by making the product of the 3 integrals, we will obtain the expression of SPF In Vitro.
This method was originally described by B. Diffey and J. Robson (JSCC 40. 127-133 - 1989). It is now widely used and recognized by international bodies.
4. OPERATING CONDITIONS FOR CARRYING OUT THE STUDY
4.1. Materials and methods
4.1.1. Laboratory materials
We use the following equipment in our laboratory:
- A UV spectrophotometer, UV-2600 (Shimadzu) equipped with a UV source and a monochromator as well as an integrating sphere capable of transmitting a flow of UV energy between 290 and 400 nm. The wavelength increment is 1nm.
- An AX124 (OHAUS) precision balance is used to control the amount of product deposited.
- A solar simulator, Suntest CPS + (Atlas) to reproduce sunlight and take into account the possible photodegradation of the sample tested.
- An oven (maintaining a temperature within the range of 27°C (±2°C) to 32°C (±2°C)) (Aqualytic AL185 (LIEBHERR)) allowing the sample to dry in the dark.
4.1.2. Application support
The sample is spread on polymethyl methacrylate (PMMA) Sunplate plates (Helioscience) (5x5cm) having a rough phase obtained by sandblasting. PMMA is the reference material recognized by experts in the field.
4.2. Product tested
4.2.1. Sample reception
The study promotor is responsible for the initial identification, composition, purity, as well as all the characteristics allowing the best definition of the products tested before the start of the study. The products will also have passed the stability tests, and will comply with good laboratory practices, to ensure that the results obtained are significant of the behavior of the products even after prolonged storage.
4.2.2. Product storage
The product is stored after referencing upon receipt. Storage took place away from heat and humidity. The samples are kept for 6 months after the analysis.
4.2.3. Deposit
The sun protection product to be tested is spread on the rough side of a PMMA plate, at an application rate of 1.2 mg /cm² (±1.5%) as it is recommended by ISO 24443 :2021.
4.2.4. Spreading
The goal is to make the film as homogeneous as possible.
The PMMA plate is weighed before and immediately after spreading the product using a precision balance. It is essential to limit the evaporation of the product during the weighing process.
Once the product has been deposited on plate surface, it should be spread immediately over the entire surface using light movements with the end of a finger previously saturated with the sunscreen product with at least four passes from the top to the bottom of the plate.
The product should be spread in a two-step process as indicated in ISO 24443: 2021:
- First, spread the product over the entire plate surface, using circular movements, with at least four passes from the top to the bottom of the plate. At the end of this first stage, the plate is turned (a quarter turn) to alternate passages, with minimal pressure.
- Then, spread the sample on the plate surface by alternating horizontal and vertical movements by repeating at least three alternating passes with moderate but increased pressure. The second phase should be realized, with moderate, but increased pressure.
A specific procedure indicating the following steps is included in a protocol deposited in the laboratory according to the physico-chemical characteristics of the product to be tested.
4.2.5. Sample selection
The procedure will be performed a second time if:
- The film has major application defects,
- A sample gives abnormal values.
4.2.6. Irradiation
The sample is exposed to 2 minimal erythemal doses "MED".
The MED value was chosen at 550 W / m2, this value corresponding to exposure to an overhead sun. With this standard sunlight, while receiving 2 MED, the product will receive: 400 J / m2.
4.2.7. Calibration
The performance of the spectrophotometer must be checked at regular intervals by the measurement of defined reference materials.
A test carried out in three parts is necessary:
- Dynamic range of the UV spectrophotometer;
- Linearity test of the UV spectrophotometer;
- Wavelength accuracy test.
4.3. Calculation methods
4.3.1. SPF determination
The in vitro SPF is calculated as follows:
4.3.2. PFUVA determination
In vitro UVA protection is expressed from the entire residual UVA spectrum that has passed through the same layer of cream.
4.3.3. CW determination
In the calculation, λc corresponds to the wavelength for which the area under the absorption curve reaches 90% of the total area from 290 nm to 400 nm. The critical wavelength will therefore be determined according to the formula:
The wavelength λc of the product tested is obtained by calculating the arithmetic mean of the different measurements: all the selected measures are taken into account for the calculation of the statistical dispersion.
4.3.4. Standard deviation determination
The SPF in vitro standard deviation “s” is given by the following Equation (5):
The PFUVA standard deviation is calculated by the same equation (5) by changing the SPF in vitro value by the PFUVA.
4.4. Statistical expression of results
The mean protection index of the preparation studied is obtained by calculating the arithmetic mean of the protection indices of each test.
Calculations are obtained using specific software, easy to use, which allows immediate access without any manipulation to all the calculations necessary to obtain the values.
REPORT: In vitro method for the determination of sun protection factors 8/10
5. RESULTS AND CONCLUSIONS
5.1. Results
5.2. Observations on the product and measures
The product may display an SPF 50 as well as the UVA logo because the corrected ratio ≤ 3 is respected.
All sun protection factors (SPF, Ratio SPFdisplayed / UVA, CW) are compliant.
Results obtained show an excellent quality of the formula studied.
6. CONFIDENTIALITY
6.1. Final report
This final report is given to the promoter who can photocopy it for his commercial needs.
6.2. Confidentiality and data storage
All information concerning the products to be studied such as patents, formulas, raw materials, manufacturing processes provided by the promoter of the studies will be de facto considered confidential and will remain the property of the promoter and may not be disclosed except with the written consent of the latter.
Jean Claude HUBAUD
Scientific direction