Adipose tissue concentrations of dioxins and dibenzofurans, titers of antibodies to Epstein-Barr virus early antigen and the risk for non-Hodgkin lymphoma.

A rapid increase in the incidence of non-Hodgkin lymphoma (NHL) has been reported in many countries. Exposure to certain pesticides or organochlorines has been shown to be a risk factor. Epstein-Barr virus (EBV) is a human herpesvirus that has been associated with some subgroups of NHL, such as Burkitt lymphoma and lymphomas related to severe immunosuppression. In this study we measured concentrations of dioxins and dibenzofurans in 33 NHL cases and 39 surgical controls. For 23 of the cases and 32 of the controls EBV titers were also available. Median titer of antibodies to EBV early antigen (EA) IgG was higher in patients than in controls. Concentrations of dioxins and dibenzofurans were divided into two groups according to the median concentration for the controls. Unconditional logistic regression analysis was performed adjusting for sex, age, and body mass index. For several higher chlorinated congeners increased risk was found for patients in the high-concentration and high-titer group. For toxic equivalency factor >27.79 and EA>80 an odds ratio of 2.8 with 95% confidence interval 0.52-18 was calculated. These results indicated that current exposure to certain organochlorines in combination with EBV might increase the risk for NHL.

Concentrations of organochlorines related to titers to Epstein-Barr virus early antigen IgG as risk factors for hairy cell leukemia.

Hairy cell leukemia (HCL) is a rare chronic B-cell malignancy that, according to modern classifications, is a subgroup of non-Hodgkin lymphomas (NHLs). A rapid increase in incidence of NHL has been reported in many countries. The reasons for this increase are largely unknown, but exposure to organochlorines has been suggested as a risk factor. Epstein-Barr virus is a human herpesvirus that has been associated with certain subgroups of NHL. In this study, we measured lipid adjusted blood concentrations (in nanogram per gram) of 36 congeners of polychlorinated biphenyls (PCBs), p, p'-dichlorodiphenyldichloroethylene (p,p'-DDE), hexachlorobenzene (HCB), and four subgroups of chlordanes (trans-nonachlor, cis-nonachlor, MC6, and oxychlordane) in incident cases of HCL and controls from the general population. We obtained results on organochlorines and antibodies for 54 cases and 54 controls. Titers of antibodies to the Epstein-Barr early antigen and Epstein-Barr nuclear antigen, measured as P107, were correlated to concentrations of organochlorines to evaluate the possibility of an interaction between these factors in the pathogenesis of HCL. We found no significant difference in lipid-adjusted blood concentrations of total PCBs, p,p'-DDE, HCB, or the sum of the chlordanes between cases and controls. Titers of antibodies to Epstein-Barr early antigen IgG [Greater and equal to] 40 were correlated to an increased risk for HCL. This risk was further increased in those with a level above the median value of p,p'-DDE, HCB, or the sum of the chlordanes, suggesting an interaction between Epstein-Barr virus and a higher concentration of these chemicals. We also found increased risk for the sum of immunotoxic PCB group.