An hypothesis for the induction of leukemia by benzene.

Benzene has the sad privilege of being the only industrial chemical inducing leukemia in susceptible individuals chronically exposed to its vapors. Hence, benzene has been included in the list of human carcinogens. Acute myeloblastic leukemia and erythroleukemia are typical examples of benzene leukemia. Most cases show some features in common: 1) development after many years of exposure and, in some cases many months after leaving the toxic atmosphere; 2) leucopenia or moderate degree of leucocytosis; and 3) splenohepatomegaly discrete or absent. Finding of an antecedent of pancytopenia reinforces the suspicion of benzene as the causative agent. There is still no agreement about the role played by benzene in chronic types of leukemia. In assessing diagnosis of benzene leukemia much importance has been attached by French authors and by myself to the demonstration of benzene in blood or in bone marrow aspirates or biopsies. Treatment of benzene hemopathy based on the oral administration of "anti-benzene compounds" such as methyl-donors and thiol-aminoacids is proposed here based on personal research in rabbits, in leukemic patients treated by benzene in the past and on myself as a volunteer. In pre-leukemic states, lowering the benzene burden of the bone marrow might prevent the further development of acute leukemia. Recently, I found out that: 1) benzene can be converted to phenol in the bone marrow independently of liver oxidizing enzymes; 2) benzene injected in the femoral artery of the rabbit can provoke histological changes at the isolated tibial marrow.