Is using a camphor liquid made for warm mist humidifier dangerous? I have a cough and congestion.

Xlear. Your doc may tell you that you have a sinus infection. You can use a natural product called xlear (pronounced "clear") to clean out nasal (oxymetazoline) passages and break up the biofilm where germs multiply. Tastes good too! Please skip the camphor and just use a warm mist humidifier.