…on Wiki and in a BASF PDF, I see it listed as having peak protection ~350 nm. This means it protects in the UVAI part of the spectrum. However, skinacea lists it as protecting from UVAII (which it still does cover). Does this imply that it’s inadequate in UVAI protection? Also, how weary should I be of the BASF ppd estimator? There are some Ombrelle sunscreens I want to try, but no labelled ppd (I wish they’d use ppd 🙁 ). Thanks!
Protection offered by sunscreens occurs on a curve, UVA II is 320 to 340 nm and UVA I is 340 to 400nm.
While the peak of Uvinul A Plus (DHHB) is in the 350nm region, it still offers protection in the 320 to 340 nm area. As well as beyond the 350 nm peak.
UVB sunscreens also tend to extend into the UVA I region, and since most sunscreens contain a mixture of UVA and UVB filters, you should be well covered.
However, there is a lack of sunscreens that have a peak in the 320 nm to 340 nm range, and there are newer ones being developed to target that area – unfortunately they don’t have approval anywhere yet.
The BASF Sunscreen Simulator is for formulation use only. The only way to know the UVAPF or UVB protection offered by a sunscreen is to test it on a human panel, or in vitro for UVAPF (COLIPA Method).
You can have two identical sunscreens, but due to differences in production have an SPF of 5 or 50. The distribution of sunscreen chemicals in the product is really important for sunscreens, as well other ingredients can increase or reduce the efficacy of a sunscreen.
Unfortunately the simulator can’t account for those.