Mosquito-repellent incense is a common mosquito repellent product whose main ingredients include dextromethrin and other prescribed pyrethroid insecticides. These ingredients are low-toxic insecticides allowed by the state, ensuring the effectiveness of mosquito repellent while reducing the potential harm to the human body. In addition to the chemicals widely used in modern mosquito coils, different formulations have historically been used to make mosquito coils. For example, in the Jiangnan region of the Song and Qing dynasties, mosquito-repellent incense containing rosin powder, mugwort powder, tobacco leaf powder, small amounts of arsenic and sulfur were used, and these traditional formulations proved to be very effective at repelling mosquitoes at the time.