t(14;18) Translocations in Dioxin-Exposed Workers.

OBJECTIVE:To determine if occupational exposure to dioxins is associated with an increased frequency of t(14;18) translocations. METHODS:A cross-sectional analysis of serum dioxin levels and t(14;18) frequencies in peripheral blood mononuclear cells in 218 former chemical plant workers and 150 population controls. RESULTS:The workers had significantly higher geometric mean serum levels of 2,3,7,8-TCDD (26.2 vs 2.5 ppt) and TEQ (73.8 vs 17.7 ppt) than controls. There were no significant differences in the prevalence or frequency of t(14;18) translocations in the workers compared to controls. Among former workers with current or past chloracne who were t(14;18) positive, the frequency of translocations significantly increased with quartiles of 2,3,7,8-TCDD and TEQ. CONCLUSION:Chloracne appears to modulate the association between dioxin exposure and increased frequency of t(14;18) translocations.