Longer term Benzene side effects, i.e. – exposures of a year or longer, results mostly in effects on the blood. Benzene that is inhaled passes through the lungs into the bloodstream. If it is eaten it passes through the intestines into the bloodstream. Benzene exposure then affects red blood cells and bone barrow, leading sometimes to anemia or increasing the risk of infection by harming the immune system. In the longer term, consistent exposure to Benzene causes cancer, specifically leukemia. With Benzene, cancers such as acute myelogenous leukemia, lymphatic system cancers, and other cancers related to blood, all become more common as exposure levels increase. Symptoms of leukemia include fever, weight loss, bleeding, and prolonged fatigue. Benzene cancers and benzene leukemia can take decades to develop depending on the level of exposure. See your doctor if you display any of these Benzene side effects and mention when you think you may have been exposed to Benzene.