Chemical Tanker Crews Face Chronic Benzene Exposure Linked to Leukemia

Deck crews on tankers transporting gasoline and petrochemical cargoes are routinely exposed to benzene, a known human carcinogen classified as Group 1 by the International Agency for Research on Cancer. A study published in Annals of Work Exposures and Health measured benzene biomarkers in alveolar air and urine among deck crews on gasoline tankers, confirming occupational exposure during loading, unloading, and tank cleaning operations. Increased rates of leukemia have been found among tanker crews, with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) identified as elevated risks. Critically, benzene exposure has been detected even in accommodation areas during cleaning and gas-freeing operations, meaning crew members not directly handling cargo are also at risk. The human cost is severe: benzene attacks the bone marrow, reducing production of red blood cells, white blood cells, and platelets. This leads to anemia, immune suppression, bleeding disorders, and ultimately blood cancers that may not manifest until years or decades after exposure. A seafarer who spends five years on chemical tankers in their twenties may develop leukemia in their forties, long after leaving the industry, making it difficult to establish occupational causation for compensation claims. This persists because the petrochemical supply chain depends on chemical tankers, and benzene is one of the highest-volume chemical cargoes globally. Vapor recovery systems at terminals are expensive and inconsistently deployed, particularly at ports in developing nations where much of the world's petrochemical trade occurs. Personal protective equipment like supplied-air respirators is available but impractical to wear continuously during multi-hour loading operations in tropical heat. Occupational exposure limits vary dramatically between flag states, and monitoring compliance requires biological sampling that most tanker operators do not perform. The long latency period between exposure and disease means the health consequences never create an acute crisis that forces immediate regulatory action.