Volume 100 of the IARC Monographs, A Review of Human Carcinogens, covers all agents previously classified by IARC as "carcinogenic to humans (Group 1)" and was developed by six separate Working Groups: Pharmaceuticals; Biological agents; Arsenic, Metals, Fibres, and Dusts; Radiation; Personal Habits and Indoor Combustions; Chemical Agents and Related Occupations. This Volume 100A covers Pharmaceuticals, specifically Busulfan, Chlorambucil, Methyl-CCNU, Cyclophosphamide, Etoposide in combination with Cisplatin and Bleomycin, Melphalan, MOPP, Tamoxifen, Thiotepa, Treosulfan, Diethylstilbestrol, Estrogen-only Menopausal Therapy, Combined Estrogen-Progestogen Menopausal Therapy, Combined Estrogen-Progestogen Contraceptives, Azathioprine, Chlornaphazine, Ciclosporin, Plants containing Aristolochic Acid, Methoxsalen plus Ultraviolet A Radiation, and Phenacetin