Level 1: Effects of mosquito-repellent incense ingredients on infant health. Mosquito-repellent incense generally contains ingredients such as insecticides and aerosols. These ingredients will have an impact on the health of infants during long-term use. Among them, aerosols will release a large amount of harmful gases, such as benzene, formaldehyde, etc., which can cause damage to the baby\’s breathing, nerves and immunity. Level 2: Effects of mosquito-repellent incense usage frequency on infant health. Long-term use of mosquito-repellent incense will increase the concentration of harmful gases in the indoor air.