The slayer can divert poisoned attacks against him.
When a creature unsuccessfully attacks the slayer with a poisoned weapon or a natural weapon that would poison him, the slayer can attempt to redirect the attack to a creature within his reach (including, possibly, the creature that unsuccessfully attacked the slayer). As an immediate action, the slayer can make an attack roll against the creature to which he would redirect the poison. On a success, the poison is redirected to the target, and the target must attempt a saving throw against the poison as normal. This attack only redirects the poison and does not otherwise damage the targeted creature. This ability cannot affect a creature that attacked the slayer with a poisoned natural weapon, but it can affect a creature that attacked him with a poisoned manufactured weapon.
Pathfinder Player Companion: Potions & Poisons © 2017, Paizo Inc.; Authors: Kate Baker, Eleanor Ferron, Nathan King, Lyz Liddell, Luis Loza, Alex Putnam, Alex Riggs, and David Schwartz.