Lemon essential oil can be diluted and applied topically to your skin, as well as diffused into the air and inhaled. Some people swear by lemon essential oil as an ingredient that fights exhaustion, helps with depression, clears your skin, kills harmful viruses and bacteria, and reduces inflammation. Camphor oil is the oil extracted from the wood of camphor trees and processed by steam distillation. It can be used topically to relieve pain, irritation, and itching. Camphor is also used to relieve chest congestion and inflammatory conditions. It has a strong odour and taste and is easily absorbed through the skin.