Toxic Tolerance Passive Tree Node

"Immune to Poison".

Is this node working?

There's a lot of ground effects that I would consider poison, yet they still do damage whenever I walk through them.

Or are these simply dealing "chaos" damage.

If so, this node seems mostly worthless.

The debuff applied to these ground effects say "poisoned" but says you take chaos damage. Technically I shouldn't be able to be poisoned but it says I am.. probably why there is confusion.