IMMUNOMODULATORY EFFECTS OF OCCUPATIONAL EXPOSURE TO MANCOZEB

The effects of occupational exposure to ethylene-bis-dithiocarbamate o f manganese and zinc on the immune system were evaluated in a group of mancozeb-exposed manufacturers and controls. The immune system tests revealed the following: (a) lymphocyte proliferative responses trigger ed by different activators and mitogen-induced IL-2 production were hi gher in exposed subjects than in controls; (b) production of monocyte/ macrophage-derived IL-1 and polyclonal IgG and IgM, by beta-lymphocyte s, did not differ between exposed subjects and controls; (c) percentag es and absolute numbers of total T-cells, T-helper cells, T-suppressor /cytotoxic cells, activated T-cells, total beta-cells, and natural kil ler cells were similar in exposed subjects and controls; (d) serum imm unoglobulin classes and complement fractions were within the range of normality; and (e) rheumatoid factor and non-organ-specific serum auto antibodies were absent in exposed and control subjects. An increase in T-cell functional response was found in the exposed group, suggesting a slight immunomodulator effect of mancozeb in conditions of low-leve l, prolonged occupational exposure.