Disodium EDTA

Say itdye-SOH-dee-um ee-dee-tee-AY

Odorless.

What it is: There to carry, keep or colour the perfume, not for its smell.
What perfumers do with it: Locks up trace metal ions from water that trigger discoloration and oxidation
Worth knowing: A calcium form of EDTA is used in hospitals to pull lead out of the blood.
Known in: Twilly d'Hermès (Hermès, 2017)
Also called: disodium ethylenediaminetetraacetate; tetrasodium EDTA (cousin)

On the label of 8 of the 1080 perfumes read so far

Sources