Article Malathion and dithane induce DNA damage in Vicia faba Shashi Kiran Arya, Ilika Ghosh, Ritesh Banerjee and Anita Mukherjee Abstract The increasing use of pesticides such as malathion and dithane in agriculture causes environmental muta- genicity. However, their genotoxicity in edible crops is seldom assessed. In this study, the genotoxic potential of malathion and dithane was evaluated in the roots of Vicia faba L. All three concentrations (0.05, 0.1, and 0.2%) of malathion and dithane tested resulted in a significant decrease in root length and inhibited seed germination. Cytological observations showed that the mitotic frequency in the root meristematic cells decreased parallel to the increase in concentrations, and the increase in chromosome aberrations and micronuclei frequency was concentration dependent. Alkaline comet assay revealed significant onset of DNA damage at all tested concentrations. For the randomly amplified polymorphic (RAPD)-polymerase chain reaction (PCR) analyses, 10 random RAPD primers were found to produce 116 unique polymorphic RAPD band fragments of 223–3139 bp. Each primer generated 3–15 RAPD bands on an average. The percentage of polymorphic DNA fragments was higher in malathion-exposed plants than dithane ones. The changes in RAPD profiles included disappearance and/or appearance of DNA bands in malathion and dithane treatment. Hence, DNA damage observed by the cytogenetic endpoints and comet assay corroborated with RAPD-PCR analysis. A total of 15 new protein bands of molecular weight ranging 11.894–226.669 kDa were observed in roots of Vicia plants that were exposed to the pesticides. The number of new protein bands was higher in malathion- treated DNA samples than in dithane-treated ones. Based on the results, we conclude that the pesticides can alter genomic template stability and change protein profiles. Malathion was more genotoxic than dithane. Therefore, RAPD assays can be useful in determining genotoxicity of pesticides in V. faba and other crops along with other quantitative parameters. Keywords Dithane, malathion, cytogenotoxicity, SDS-PAGE, RAPD, Vicia faba Received 5 October 2016; Revised 10 July 2017; Accepted 20 July 2017 Introduction In recent years, the use of pesticides in modern agri- cultural practices has increased enormously. As a consequence, their constituents are released into the environment causing potential hazard to both humans and other nontargeted organisms. The fungicide dithane, also known as mancozeb, belongs to a class of chemicals known as ethylene bis-dithiocarbamates (EBDCs). It is used to prevent crop damage from fungal diseases in the field and from deterioration during storage. The active ingredient of the break- down products of dithane and other EBDCs (Environ- mental Protection Agency, 1992) is ethylenethiourea, which is of major toxicological concern. Malathion (S-1,2-bis(ethoxycarbonyl) ethyl O, O dimethyl phos- phorodithioate is a broad-spectrum aliphatic organo- phosphate insecticide widely used for both domestic and commercial agricultural purposes (OEHHA, Cell Biology and Genetic Toxicology Laboratory, Department of Botany, University of Calcutta, Kolkata, India Corresponding author: Anita Mukherjee, Cell Biology and Genetic Toxicology Laboratory, Department of Botany, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700019, India. Email: anitamukherjee28@gmail.com Toxicology and Industrial Health 1–12  The Author(s) 2017 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0748233717726877 journals.sagepub.com/home/tih