Does La Roche-Posay’s Effaclar Duo Cause Cancer?
There has been a lot of concern recently because in the USA the La-Roche Posay Effaclar Duo was recalled due to the presence of Benzoyl Peroxide. This ingredient, in certain conditions (e.g. warm temperatures) can break down in Benzene which is a carcinogen.
Fortunately, the UK product does not contain this ingredient, meaning there is no risk for UK Consumers buying this product.
Why does the US version of La Roche-Posay Effaclar Duo contain Benzoyl Peroxide?
The La Roche-Posay Effaclar range is intended to help fight acne. Benzoyl Peroxide was used in the US version of this product because it helps to kill bacteria and thus helps to fight acne.
In the UK version they use Niacinamide, Salicylic Acid and LHA instead:
- Niacinamide: Reduces inflammation and controls sebum production to help prevent breakouts
- Salicylic Acid: Penetrates pores to dissolve excess oil and unclog trapped debris
- LHA (Lipo-Hydroxy Acid): Gently exfoliates skin to clear dead cells and promote cell renewal
Why is the UK Version of Effaclar Duo safer?
The primary reason is because the MHRA (UK Health Body) has stricter regulations around the use of Benzoyl Peroxide. Whilst the Food and Drug Administration (FDA) allows products to contain up to 10% Benzoyl Peroxide for over-the-counter products the UK has much stricter rules which prompts brands to use more gentle but effective alternatives.
How dangerous is Benzoyl Peroxide?
Studies have shown that Benzoyl Peroxide can breakdown into Benzene even at room temperature. In the USA the FDA considers 2 parts per million of Benzene of fewer to be an acceptable level and anything beyond that is considered unsafe.
The same study also found that exposure to heat dramatically elevates the rate at which Benzoyl Peroxide converts to Benzene. The products were incubated at 50 degrees Celsius and within 2 weeks showed large traces of Benzene.
Is Benzoyl Peroxide Banned in the UK?
No, Benzoyl Peroxide is not banned in the UK, but its use is more tightly regulated—especially in leave-on treatments. That’s why most cosmetic-grade acne products like Effaclar Duo exclude it in favour of gentler actives.
How to Identify the Safe UK Version
If you’re looking to buy Effaclar Duo and want to avoid Benzoyl Peroxide:
- Check the ingredient list: Avoid any version listing “Benzoyl Peroxide”
- Look for “Unifiant” or “+” in the name: These are often UK/EU designations
- Buy from reputable UK retailers: This ensures you’re getting the region-specific version
- Avoid US imports via marketplaces: Many products shipped internationally may not match local safety standards
What alternatives can I use instead of Benzoyl Peroxide?
Alternatives include Salicylic Acid, Niacinamide, LHA, and Azelaic Acid. These skincare ingredients help reduce breakouts, unclog pores, and calm inflammation without the risk of benzene formation.
