Erythrocyte membrane protein damage by phenoxyacetic herbicides and their metabolites

In the present work, we describe the effect of chlorophenoxyl herbicides 2,4-dichlorophenoxyacetic acid (2,4-D), 4-chloro-2-methylphenoxyacetic acid, and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), and their metabolites (2,4-dichlorophenol, 4-chloro-2-methylphenol, 2,4-dimethylphenol, and 2,4,5-trichlorophenol) on the activity of ATPase and the corresponding protein damage (measured by loss of -SH group). Basic compounds caused an increase in the activity of the enzyme by 7-9% (at concentration 1 mM). For higher concentrations (2 and 4 mM), a decrease in the ATPase activity was observed for all investigated compounds. The increase of the free -SH group content was observed for all compounds. More profound changes in investigated parameter values were observed for metabolites (when compared to basic compounds) which may suggest their higher toxicity. (c) 2005 Elsevier Inc. All rights reserved.