Bronopol

Bronopol Description

Bronopol, also known as bronosol, is an organic compound first synthesized in 1897. It is used as a preservative in numerous commercial applications thanks to its broad-spectrum antimicrobial activities. The ingredient name you’ll see on the label is 2-bromo-2-nitropropane-1,3-diol.

While it does an exemplary job of preventing bacterial growth (which is always a good thing, as some cosmetics without preservatives would be prone to rapid microbial growth) in both rinse-off and leave-on products, it is also known to cause allergic contact dermatitis. There are several other, equally effective preservatives that do not present this potential for side effects.

In its raw form, bronopol appears as white crystals. Use levels in cosmetics range from 0.02–0.05%, a testament to this preservative’s potency.