What are some of the risk factors for leukemia?

Bad luck.: Leukemia is typically due to what i call luck of the worst kind. There are some risk factors: radiation, exposure to benzene, immunodeficiency syndromes, congenital bone marrow disorders, previous treatment with chemotherapy, down syndrome, and certain pre-leukemia conditions, .

Hard to say...: Many times we don't know what causes leukemia or lymphoma, irrespective of type. The process is probably multifactorial and has a strong genetic component. In a small subset of cases exposure to various toxins like paint fumes, or to radiation, can also cause it, but this represents only a small percentage of patients. There is also an association with certain viruses (ebv, htlv).