Are there dangers in the topical use of succinic acid?

To date, succinic acid is considered safe and well-tolerated by all skin types. The adverse effects often cited in the literature are mainly hypothetical and require further research. According to the Globally Harmonised System (GHS), succinic acid is not classified as toxic, corrosive or irritating to the skin, which attests to its low risk in cosmetics. Here are the main side effects reported following the use of succinic acid:

• Potential skin sensitisation: Although there is no clear evidence to suggest that succinic acid is a skin sensitiser, it is important to remain vigilant. In rare cases, repeated application may lead to skin sensitisation

• Potential local irritation: Skin irritation is the most common effect associated with the use of succinic acid, particularly in individuals with sensitive skin or pre-existing dermatological conditions. Symptoms may include redness, itching, or burning sensations. Being classified among weak organic acids, succinic acid poses irritation risks at high concentrations, similar to those of other acids, such as phosphoric acid.

• Sometimes, an eye irritation: In the event of direct contact, succinic acid can cause eye irritation. Due to its slightly corrosive nature, it is essential to avoid any contact with the eye area.

• Risks associated with prolonged exposure: Exposure to high concentrations of succinic acid in the air, particularly through sprays, can lead to respiratory irritations. Exposure limit values (MAK) of 2 mg/m³ have been established to prevent these risks. On the other hand, topical application of succinic acid generally does not pose a risk of respiratory irritation, but it is essential to adhere to the recommended concentrations and carry out patch tests to avoid skin irritations.

• A potential interaction with other active ingredients: The succinic acid could potentially interact with other cosmetic ingredients, particularly those based on acids, such as salicylic acid, which could increase skin irritation. It is advised to consult a healthcare professional before combining several active ingredients in a skincare routine.

Currently, there is relatively little clinical data available to assess the safety of succinic acid during pregnancy. Generally, it is recommended that pregnant women exercise caution with cosmetic products containing new ingredients or acids. However, to date, succinic acid is not considered a harmful ingredient to avoid during pregnancy. Regarding breastfeeding women, there is also no substantial evidence to suggest that succinic acid is harmful during breastfeeding.

If you have any doubts about your skincare routine during your pregnancy or breastfeeding, do not hesitate to seek advice from a healthcare professional.

In order to minimise the risks of irritation and other discomforts associated with succinic acid, it is recommended to follow these usage precautions:

• Patch-test: Before incorporating a product containing succinic acid into your skincare routine, it is recommended to perform a patch test. Apply a small amount to a localised area and monitor for any skin reaction over 24 to 48 hours to minimise the risk of irritation.

• Using succinic acid at the recommended doses: To avoid any risk of irritation, it is essential to use products containing succinic acid at the concentrations recommended by manufacturers or health professionals. Overuse or excessively high concentrations can exacerbate side effects.

• Systematically apply sun protection: Although succinic acid is not classified as a photosensitising active ingredient, it is wise to use sun protection after its application, especially in cases of prolonged exposure to the sun.

• Avoid contact with sensitive areas: We recommend not applying succinic acid to particularly sensitive areas, such as the eye contour or mucous membranes, in order to prevent irritations and other adverse effects.

• Consulting a dermatologist: For individuals with dermatological issues, it is recommended to consult a dermatologist before using products containing succinic acid. This ensures appropriate use, especially in cases of underlying skin conditions.

• SAXENA R. & al. Production and Applications of Succinic Acid. Current Developments in Biotechnology and Bioengineering (2017).

• HARTWIG A. & al. Succinic acid. The MAK-Collection for Occupational Health and Safety (2018).