Hi.. Thanks for the query.. I have gone through your query and can understand your concerns.. As per your question loss of taste and smell with an altered smell and taste sensation of smelling a chemical like smell and taste is commonly seen in case of Sinus infection and inflammation of sinus.. As you have Dry and burning sinuses the most probable cause of altered taste and smell is Sinusitis.. The other causes can be upper respiratory tract infection, nerve damage, head injury etc.. Nothing to worry, consult an Otolaryngologist and get evaluated and after a thorough evaluation if sinus infection is diagnosed antibiotics, decongestants, Steroid nasal spray, saline irrigation and steam inhalation can relieve.. Hope this information helps..