How EtO causes lymphoma
When inhaled, EtO is absorbed into the bloodstream and carried to the lymphoid tissues, where it acts as a DNA alkylating agent, binding directly to DNA without the need for prior metabolic activation. This causes the formation of DNA adducts, chromosomal damage, and mutations in lymphoid cells, which interfere with normal cell growth and lead to the transformation to cancer.
A case-control study involving over 2,300 lymphoma cases across six European countries found that medium-to-high frequency EtO exposure was associated with a 4.3-fold increase in lymphoma risk. Both the IARC and the EPA conclude that the strongest evidence linking EtO exposure to cancer involves lymphohematopoietic cancers, including lymphomas such as non-Hodgkin lymphoma and Hodgkin lymphoma, as well as leukemia and related blood cancers.
A large NIOSH cohort study also found increased mortality from lymphohematopoietic malignancies, including non-Hodgkin lymphoma, associated with high cumulative EtO exposure.