Sunscreens: SPF testing moves from volunteers to plates
The European Commission encourages moving away from SPF testing on volunteers towards the in vitro method of EN ISO 23675:2024. Under the JACOP campaign 74 products from 11 countries were tested and the two methods correlated closely.
- EN ISO 23675:2024, published in December 2024, describes the in vitro method; a hybrid method called HDRS was published at the same time, using human subjects without inducing erythema.
- In the in vitro method the product is applied by robot to acrylic plates — moulded and sandblasted — and a spectrophotometer measures UV transmission; SPF is computed by an algorithm combining the measurements from both plate types.
- Advantages: faster, cheaper, no volunteer constraints and no bias from anti-inflammatory ingredients that inflate in vivo results. Limitation: the method does not cover sticks and powders.
Source: Komisja Europejska — EU moves to more ethical sunscreen testing