Ammonia oxidizing microorganism preparations for delivery to the intranasal system, kits including ammonia oxidizing preparations for delivery to the intranasal system, and devices for administering ammonia oxidizing preparations to the intranasal system are provided. Methods of introducing ammonia oxidizing microorganisms to the intranasal system are provided. Methods of treating disorders, including neurological disorders, nasal or sinus disorders, and inflammatory disorders, with ammonia oxidizing microorganism preparations are provided.