Prolonged exposure to excessive formaldehyde may lead to swollen lymph nodes. Formaldehyde is a toxic gas, especially in newly renovated houses, if not thoroughly ventilated and exposed for a long period of time, direct occupancy can easily cause respiratory damage, such as prolonged exposure to this environment may lead to stinging eyes, cyanosis of the conjunctiva, tearing, which can lead to upper respiratory symptoms such as coughing, chest tightness, which can lead to lung lesions. Prolonged inflammatory changes in the upper respiratory tract can stimulate the development of enlargement of the surrounding lymph nodes, which may lead to enlargement of the lymph nodes around the lungs. In addition, preparation for pregnancy, pregnancy, postpartum and families with children should not live in a formaldehyde overloaded environment, it is possible to prepare for pregnancy of the newlyweds caused by certain reproductive effects, so formaldehyde must be timely prevention, must be completely emptied, and through the test that can be moved in before, can avoid harm to the human body.