Immunologische befunde bei ehemals gegenuber 2,3,7,8- tetrachlordibenzodioxin (TCDD) und seinen kongeneren exponierten arbeitern in der pestizidherstellung

A pesticide producing plant was closed in 1984 because of the incurring amount of polychlorinated dibenzodioxins and furans (PCDD/F). From 1992 to 1994 192 formet workers were investigated for their health status, especially for clinical and laboratory signs of alterations of the immune system. Parameters were blood count and differential blood count, immunoglobulins, serum electrophoresis, proliferation of lymphocytes, lymphocyte subgroups, monoclonal antibodies and L-chains in urine. The concentration of tetanus toxoid antibodies before and three weeks after vaccination and the resistance of lymphocytes in vitro against chromate was measured. Moreover the chromate resistance of lymphocytes of the 29 workers with the presumably highest exposure was compared with that of 28 external controls. Blood concentrations of PCDD/F were available of 187 workers. There was no significant correlation between the PCDD/F concentrations measured and a clinical impairment of the immune system. Furthermore, most of the immunological parameters did not correlate with the toxin concentrations. The chromate resistance of the lymphocytes stimulated with phytohemagglutinine (PHA) of the 29 persons with highest exposure was significantly lower than that of the control group. Possibly such functional parameters are more sensitive in detecting impairments of the immune system under exposure to PCDD/F.