Evaluation of Occupational Risk Factors in Non-Hodgkin Lymphoma and Hodgkin's Disease in Iranian Men

Background: Lymphoma is a malignancy, arises from lymphoid tissue. Nowadays, it is the ninth most common cancer in Iran. The risk factors of malignant lymphomas have not well determined, but since 20 years ago till now, too many epidemiological researches have been concerning either Non-Hodgkin Lymphoma (NHL) or Hodgkin's Disease (HD). It is a common usual hypothesis that idiosyncratic reaction to common physical, chemical, and viral agents could lead to lymphoma without obvious immune deficiency. Some occupations has reported to cause increasing "NHL" risks, such as rubber industry, veterinaries, uranium mining, metal working, asbestos exposing, farming, textile industry, and benzene exposing. The roles of ionizing radiation, benzene and other environmental agents have not been clear, because of the lack of confirmed evidences for relation between the occupational and environmental agents with "HD".

Methods: A case-control study with 150 cases of malignant lymphoma and 150 controls have performed in Tehran. Data have selected through face-to-face interviews about the medical and occupational histories.

Results: In this study, there was a significantly increased risk for Non-Hodgkin Lymphoma in these occupations; welders, metal workers, founders, aluminium workers OR=4.6 [Confidence Interval (CI): 1.47-14.35] and increased risk for Hodgkin's Disease in drivers OR=2.34 [(CI):0.86-6.35]. We have found out decreased NHL risk in office workers OR=0.54 [(CI):0.29-1.02] and also found out a non-significant increased NHL risk in farmers OR=1.58 [(CI):0.82-3.03]. In this study, we have found no relation between smoking and HD, or NHL.

Conclusion: The results of this study suggest that several occupations could alter the risk of Non-Hodgkin Lymphoma and Hodgkin's Disease.