Multiple myeloma is a common malignant tumor of the blood system, and there are many causes of malignant tumors, the most important of which are three factors, as follows: 1, chemical factors: mainly including all kinds of medicines, chemicals, pesticides, and some fuels, etc., for example, xylene has been proved to be a strong cancer-causing substance, and also hair dyes used in daily life, or all kinds of adhesive or chemical solvents used for home decoration. These are strong carcinogenic substances; 2, physical factors: mainly refers to various kinds of radiation, such as nuclear radiation, X-ray, microwave radiation, ionizing radiation, etc.; 3, biological factors: mainly various kinds of viruses, such as Hepatitis B virus, Hepatitis C virus, cytomegalovirus, human papillomavirus and so on.