Cancer: Higher risk of blood cancer–associated mutations in World Trade Center disaster first responders

First responders to the World Trade Center disaster have increased levels of mutations in blood cells that elevate the risk of cancer, compared with non–World Trade Center first responders, according to a study published in Nature Medicine.

During aging, mutations in blood cells accumulate as part of a phenomenon known as ‘clonal hematopoiesis’. A higher mutational burden in blood cells is detrimental, increasing the risk of blood cancer, cardiovascular disease and other disorders.

Amit Verma and colleagues studied whether environmental exposure to potential carcinogens present at the World Trade Center disaster site could result in increased levels of clonal hematopoiesis–associated mutations in first responders. Blood samples from 481 first responders present at the World Trade Center disaster (429 firefighters and 52 emergency medical service workers) were used to analyze 237 genes that are frequently mutated in blood cancer. Mutations were detected in a significantly higher number of these first responders (10% of those tested) than in firefighters not present at the World Trade Center disaster (6.7% of a control group of 255 people), after differences in age, sex and race/ethnicity were accounted for. Consistent with these findings, treatment of mice with particulate matter obtained from the World Trade Center site induced mutations in bone marrow cells.

The authors conclude that these findings provide direct evidence that first responders to the World Trade Center disaster have an increased mutational burden — beyond what would be expected during normal aging — which can lead to cancer and other types of disease.