Ethylene bisdithiocarbamate pesticides cause cytotoxicity in transformed and normal human colon cells

The effects of the fungicides Maneb, Mancozeb, and Zineb were investigated in transformed colon cells, HT-29, Caco2 and non-transformed cells, CCD-18Co. Significant decreases in viability were observed with Maneb and Mancozeb in HT-29 and CCD-18Co (80-260 mu M), and Caco2 cells (40-180 mu M). No significant decreases in viability were observed in all cell types up to 800 mu M with Zineb. MnCl2 and ZnCl2 exposure produced no loss of viability in all cell types up to 400 mu M. Light microscopy confirmed viability analysis. Lipid peroxidation was observed with Maneb and Mancozeb in cell types tested (60-200 mu M). Caspase 3/7, 8, and 9 activities were observed with Maneb and Mancozeb in cell types tested (40-200 mu M). Maneb and Mancozeb treated HT-29 and Caco2 cells demonstrated increases in manganese and zinc concentrations (20-200 mu M). The lack of toxicity observed with Zineb, MnCl2, and ZnCl2 suggests that both the metal moiety and the organic portion of these fungicides together contribute to toxicity. (C) 2012 Elsevier B.V. All rights reserved.