Acide phosphorique (E338)

Phosphoric acid (E338) is a strong inorganic mineral acid derived from phosphate rock through wet or thermal processes. In cosmetic formulations, it is primarily used as a highly effective pH adjuster capable of lowering pH to very acidic levels, making it particularly valuable in formulations requiring precise acidification such as hair relaxers, chemical peels, and nail products. Formulators favor it over organic acids in certain applications due to its non-volatile nature, cost-effectiveness, and mild chelating properties that can help stabilize formulations against metal ion contamination.