<p>This study aimed to investigate differences in health impairment among workers at coking plants and calcium carbide plants under varying occupational exposures. Male employees (<i>n</i> = 325) from a coking plant and (<i>n</i> = 653) from a calcium carbide plant in western Inner Mongolia were selected as subjects. Demographic and occupational health examination data were collected to compare health indicators both pre- and post-employment for each individual and between plants. Cox regression, multiple linear regression, and logistic regression analyses were employed to assess the impact of occupational exposure. Results indicate that employees from both plants exhibited elevated blood pressure after employment, with coking plant workers demonstrating a 1.98-fold higher risk of hypertension than calcium carbide plant workers after adjusting for age, smoking, and alcohol consumption. Hematological analysis revealed significant post-employment elevations in white blood cell, neutrophil, and lymphocyte counts across both plant cohorts, the coking plant demonstrated abnormal risk levels exceeding those of the calcium carbide facility by over 1.5-fold. Divergent trends emerged in other parameters: coking plant workers exhibited decreased red blood cell, hemoglobin, and platelet counts post-employment, whereas their calcium carbide counterparts showed opposing increases. Monocyte counts displayed an upward trajectory at the coking plant but a downward tendency at the calcium carbide facility. Correlation analysis reveals a significant association between the elevated detection rate of hepatic haemangiomas in coking plant workers and their occupational exposure to polycyclic aromatic hydrocarbons (PAHs). Conclusions indicate that occupational exposure in both coking and calcium carbide plants is associated with adverse health effects, though coking plants pose more pronounced health hazards due to exposure to characteristic pollutants.</p>