[Immune effects of endocrine disruptors]

To evaluate chronic immune effects of endocrine disruptors, serum autoantibodies and immunoglobulin concentrations were studied in patients with Yusho. Autoantibodies were present in some patients of Yusho; 45.6% for antinuclear antibody, 12.7% for rheumatoid factor and 11.1% for thyroglobulin antibody. LE factor was not detected. Serum levels of immunoglobulin A(IgA), immunoglobulin G(IgG) and immunoglobulin M(IgM) were elevated in 12.7%, 24.1% and 8.9%, respectively. Thyroglobulin antibody was detected in 19.5% of Yusho patients with high PCB concentration(higher than 3.0 ppb), and in only 2.5% of patients with low PCB concentration (lower than 2.9 ppb). Furthermore, the mean absolute density of CD4 positive lymphocytes was higher in patients with high PCB concentration than in patients with low PCB concentration. We conclude that autoantibodies in patients with Yusho are frequent, and it may be associated with the increase of helper/inducer T cells. Effects of lactational exposure to chlorinated dioxins and related chemicals on lymphocyte subpopulations in Japanese babies were also studied. Estimated total TEQ intakes of chlorinated dioxins and related chemicals from the breast milk correlated negatively with the percentages of CD8 positive lymphocytes. It is showed that exposure to background levels of chlorinated dioxins and related chemicals through breast milk may cause some immunologic disorder.