Evaluation of host resistance and immunity in mice exposed to the carbamate pesticide aldicarb.

Adult female Swiss-Webster and B6C3F1 mice received distilled water only or water containing 0.1, 1.0, 10, 100, or 1000 ppb of aldicarb daily for 34 days. The target concentration of aldicarb present in the 10 ppb dosing solution was analytically verified on a daily basis as was its stability over a 48-hr period. To develop an immune profile of this compound, functional parameters measured after exposure included resistance to infectious viral challenge; quantitation of splenic antibody-forming cells to sheep erythrocytes and circulating serum antibody levels; splenic lymphocyte blastogenesis to T- and B-cell mitogens; and mixed-lymphocyte culture response. To supplement the functional assays, complete blood counts, differential leukocyte counts, and body and relative organ weights were measured. In addition, gross and histopathologic examinations of tissues relevant to the immune system were performed. The absence of significant effects on any of these parameters suggests that aldicarb at environmentally relevant exposure concentrations is not immunotoxic in rodents.