What Is Non-Nano Zinc Oxide SPF — And Why It Matters for Reefs

The difference between nano and non-nano zinc oxide in sunscreen is not a marketing detail — it is a reef conservation issue. Non-nano zinc oxide stays on the skin surface, offers full-spectrum UV protection, and does not enter coral tissue. This guide explains the science behind particle size, why it matters for the Great Barrier Reef, and what to look for on a label.