Could you specify a time period? When you say "warriors", I assume you mean pre-WW1, when there were large-scale deployments of chemical weapons, which would certainly fit your criteria of being used in battle. Because I'm not sure whether you want to hear about the use of poisonous/chemical weapons in the modern era, I'll instead direct you to an enlightening response on the subject, here:
This is by u/QVCatullus who responded to a similar question to yours, but one revolving around poisoned arrows in particular.