Hi. First of all, sorry for the late answer.
It is currently impossible to get the actor collided by a particle, or check in the actor if it collided with a particule from a spawner. Mostly because it would cause performances issues.
However, depending on what you want to do, you can try to use the Particle Events feature in the PopcornFX Editor(edit-cf: 'OnCollide' Event), coupled with the Event Listener in blueprints. Basiclly, it will allow you to broadcast an event from your effect, triggering a custom delegate in blueprints. Inside your delegate's scope, you will be able to recover any particle field that was previously registered.
Let me know if it helped you.