The hematopoietic stem cell compartments in mice during and after long-term inhalation of three doses of benzene.
Female BDF1 mice were exposed for 16 weeks to airborne concentrations of 100, 300, and 900 ppm of benzene, 6 h per day, 5 days per week. Bone marrow hemopoietic stem cell compartments and peripheral blood cell counts were studied using clonal assays and standard methods. Dose-dependent depressive effects were observed on all stem cell compartments. Only the erythroid colony-forming units (CFU-E) compartment was depressed during exposures to 100 ppm; CFU-E were more sensitive than the erythroid burst-forming units (BFU-E), spleen CFU (CFU-S), or G-M CFU (CFU-C) during exposure to 300 ppm or 900 ppm. Lymphocytopenia was observed in the peripheral blood. After benzene-free intervals, a regeneration of lymphocyte numbers and slow normalization of stem cell numbers was seen. Complete recovery from the 16 weeks exposure to 300 ppm was seen between 73 and 185 days.
Seidel
H J
HJ
Institute for Occupational and Social Medicine, University of Ulm, FRG.
Barthel
E
E
Zinser
D
D
D000280:Administration, Inhalation; D000740:Anemia / Q000097:blood / Q000139:chemically induced; D000818:Animals; D001554:Benzene / Q000633:toxicity*; D003114:Colony-Forming Units Assay; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004906:Erythrocyte Count / Q000187:drug effects; D005260:Female; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D007958:Leukocyte Count / Q000187:drug effects; D008214:Lymphocytes / Q000187:drug effects; D051379:Mice
D001554:Benzene