Formaldehyde is harmful to the human body in the following ways: formaldehyde has an irritating effect, short time exposure to high concentrations of formaldehyde, the skin mucous membranes and respiratory tract has an irritating effect, there may be tears, sore throat, cough, shortness of breath, breathing difficulties and other symptoms. In addition, formaldehyde also has a sensitizing effect, skin contact with formaldehyde can cause allergic dermatitis, respiratory inhalation of formaldehyde may induce bronchial asthma; formaldehyde also has a mutagenic effect, prolonged multiple exposure to high concentrations of formaldehyde may lead to the occurrence of blood disorders.