Propylparaben
What it is
The n-propyl ester of para-hydroxybenzoic acid. Longer carbon chains in parabens correlate with higher estrogenic potency and lipid solubility.
What it does
Preservative in creams, lotions, shampoos, and many food products, where it keeps microbial counts low at levels typically under 0.2%.
Why it’s a concern
EFSA reviewed propylparaben (E216) as a food additive in 2004 and again in 2006, expressing concern about reproductive endpoints in male rats. The 2004 opinion did not set an ADI to zero, but EFSA removed propylparaben from the group ADI for parabens, citing the Oishi 2002 study which reported decreased sperm production and testosterone in juvenile rats exposed to propylparaben. The EU subsequently restricted propylparaben in leave-on cosmetics for children under three, and banned isobutylparaben and butylparaben outright in 2014 over related reproductive toxicity findings.
Also known as
CAS numbers
Commonly found in
Safer alternatives
- phenoxyethanol at low levels
- sodium benzoate
- potassium sorbate
Related chemical families
Sources
- EFSA Opinion on Propylparaben 2004
- Oishi 2002, Food and Chemical Toxicology