FELA: Multiple myeloma claims

How benzene exposure leads to multiple myeloma

Benzene metabolites accumulate directly in bone marrow, where they damage the hematopoietic stem cells that give rise to plasma cells. Chromosomal abnormalities and disrupted DNA repair mechanisms allow genetic mutations to build in blood-forming cells over time. Benzene also suppresses immune surveillance and alters immune signaling, conditions that allow abnormal plasma cell clones to proliferate without the regulation that would normally contain them.

A large pooled case-control study through the InterLymph consortium, involving over 2,800 multiple myeloma cases, found approximately a 42% increased risk in the highest benzene exposure categories, with some solvent subgroups reaching 63% elevated risk. Researchers concluded that the findings add important evidence for a role of aromatic hydrocarbon solvents in multiple myeloma causation. A separate meta-analysis of benzene-exposed occupational cohorts reported a relative risk of approximately 2.1 in certain high-exposure industrial populations.

Railroad workers accumulate benzene exposure through diesel exhaust in enclosed locomotive cabs and rail yards, fuel handling operations, engine maintenance, and solvent use in poorly ventilated facilities across decades of employment.