Most over-the-counter brightening serums use 1–3% phytic acid at pH 3.5–4.5. Professional-grade or targeted exfoliant serums may push to 5–7%. Your cosmetic chemist should validate the pH and chelation compatibility with your chosen preservative system before finalising the formula — ask for stability and compatibility data at the selected concentration.
Read the full guide on private label phytic acid serum manufacturer low moq →