Dextro-trans-alpha-cypermethrin, if present in qualified mosquito coil products, does not pose an absolute hazard when used in a regulated manner. If used improperly, it may cause respiratory discomfort, skin rash, dizziness and other symptoms, and in serious cases, it may lead to abnormal blood indicators. Dextro-trans-alpha-cypermethrin is an organic substance, insoluble in water, belonging to the low toxicity class of chemicals, usually used to control mosquitoes, cockroaches and other household pests. The amount of alpha-cypermethrin added to mosquito coils ranges from 0.1% to 0.3%. In daily life, reasonable compliance with the use of mosquito coils containing deltamethrin will not cause absolute harm to human beings and there is no need to worry too much. However, improper use of products containing fumonisin or exposure to higher concentration of fumonisin in daily life may cause respiratory discomfort such as dry and itchy throat, coughing and shortness of breath. Some people may also experience discomfort such as itchy skin and dizziness, and in severe cases, abnormal blood indicators. In daily life, it is recommended to buy the regular channels of fumonisin products, and stop using it and seek medical treatment if any discomfort occurs.