My voice has been horse for about a month now. i have not been sick. my throat does not hurt, i don't have a cough or runny nose. what can cause this?

See an ENT : While I am not an ENT specialist, this symptom has to be checked out by visualizing the vocal cords to rule out a lot of possibilities. Please do not neglect. Could be nothing but could be imperative not to neglect other more nasty options.

Chronic hoarseness: Good that u don't smoke. Do u use voice a lot (speaker, singer, coach, etc) where u have to shout or raise voice to be heard? May have nodules on vocal cords; remote possibility of laryngeal cancer (much more likely if u smoked) or hpv. Other possibilities: reflux, hypothyroid. See an ENT specialist who can evaluate larynx & obtain tests if needed.