Occupational exposures and haematological abnormalities among ordnance factory workers: a case control study

The lifetime exposures to an extensive list of chemical and other potentially toxic hazards were estimated for all available employees at an ordnance factory by questionnaire-based interview. Exposure histories of 32 (of 33) previously diagnosed as haematologically abnormal (cases) were compared with 322 (of 345) normals (controls). Among 'ordnance factory chemicals', modestly increased odds ratios were observed for men for acetic anhydride (2.8), stearic acid (2.8), and possibly for resorcinol (2.9), TNT (2.4) and hydroxy terminated polybutadene (HTPB) (2.4). Increased odds ratios were also observed in exposures not directly related to ordnance manufacture, including mineral acids, welding fumes, exhaust gases and insecticides. While, small numbers in the case group limit the statistical significance of reported odds ratios, one should be cautious about committing a type II error. These findings may partly explain the previously reported unusual prevalence of haematological abnormalities within the factory.