Carcinogenicidade do carbendazim

http://dx.doi.org/10.5935/0100-4042.20140214

Quim. Nova, Vol. 37, No. 8, 1329-1334, 2014

Renato C. Silva, Karina A. Barros e Antonio C. Pavão*
Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50740-540 Recife – PE, Brasil
Recebido em 03/02/2014; aceito em 10/06/2014; publicado na web em 29/07/2014

Artigo

CARCINOGENICIDADE DO CARBENDAZIM E SEUS METABÓLITOS

CARCINOGENICITY OF CARBENDAZIM AND ITS METABOLITES. The carcinogenic potential of carbendazim and its metabolites was analyzed using statistical treatment of electronic parameters obtained from DFT/ 6-311++G(d,p) and AM1 calculations. The carcinogen-DNA interaction is described in the framework of the theory of unsynchronized resonance of covalent bond as a process of electron transfer involving the HOMO and LUMO frontier orbitals. Through a Principal Component Analysis
(PCA) of the electron affinity, carcinogen-DNA interaction energy, electrostatic attraction and cell membrane permeability (dipole moment m and partition coefficient LogP) evidence was obtained showing carbendazim displays carcinogenic activity. For the metabolites of carbendazim, no evidence was found in the literature of their carcinogenic activities. However, the electronic parameters for these metabolites exhibited similarity to known carcinogens, thereby showing the importance of the results obtained in this study for a policy based on the precautionary principle.
Keywords: fungicides; chemical carcinogenesis; DFT and AM1 calculations.

INTRODUÇÃO
O fungicida benzimidazólico metil-2-benzimidazole-carbamato
(MBC), fórmula molecular C9H9N3O2, conhecido popularmente como carbendazim (Figura 1),

Figura 1. Fórmula estrutural do carbendazim

foi notícia internacional em janeiro de 2012, quando os EUA proibiram a importação do suco de laranja brasileiro devido à presença deste fungicida. Esta decisão causou um enorme impacto já que o
Brasil destina cerca de 15% das suas 1,3 milhões de