Can pinworms be passed through kissing?

Theoretically yes: Pinworms are passed by swallowing eggs so they lay their eggs around the anus and when you touch that area and then your mouth, you swallow it and they get to your intestines that way. So if you have eggs on your lips, theoretically you could pass them on to someone else by kissing them.

Unlikely to happen: You could acquire some eggs on your hands from contaminated bed sheets or under ware & then transfer to your face & lips, but that takes a lot of ifs to happen. Pw's are not passed like a virus or sore throat but do require exposure to the shed eggs of an infected person.