Cytotoxicity of the fungicide mancozeb on CHO-K1 cultures

Abstract

The cytotoxicity of the dithiocarbamate fungicide mancozeb was assessed on hamster ovary cell culture (CHO-K1), using the neutral red incorporation (RN) and total protein content (PT) assays as endpoints. Both techniques were reliable in evaluating the cytotoxic parameters of mancozeb. The RN<inf>50</inf> value calculated by probit/log curves was lower than 15 μg/ml after 24 h exposure, in the absence of fetal calf serum in the culture medium. Preincubation of mancozeb with different concentrations of rat liver submitochondrial fraction gave rise to less toxic metabolites than the parent compound. Ethylenthiourea (ETU), the final metabolite of mancozeb degradation, also showed less cytotoxicity than the original compound at short exposure times.