Evidences of DNA and chromosomal damage induced by the mancozeb-based fungicide Mancozan® in fish (Anguilla anguilla L.)

- Mancozan® induced DNA and chromosomal damage in blood cells, pointing out a genotoxic hazard to fish.
- The comet assay showed that Mancozan® induces DNA breaks through oxidative processes.
- The ENA assay demonstrated clastogenic and/or aneugenic properties of Mancozan®.
- Both assays were positively correlated, agreeing on the genotoxic ability of Mancozan®.

The formulation Mancozan®, containing mancozeb as active ingredient, is among the most widely used fungicides. Although mancozeb has been detected in surface waters, studies addressing the genotoxic risk to fish arising from the use of this formulation, testing environmentally realistic concentrations, are absent from the literature. Hence, this work aimed to investigate the DNA and chromosome damaging potential of Mancozan® (0.29 and 2.9 μg L− 1) in the European eel (Anguilla anguilla L.), after a short-term exposure (3 days), through the adoption of the comet and the erythrocytic nuclear abnormality (ENA) assays. In addition, it was intended to elucidate the subjacent damage mechanisms, improving the comet assay with the adoption of the endonucleases formamidopyrimidine DNA glycosylase (FPG) and endonuclease III (EndoIII), which detect oxidized bases. The highest Mancozan® concentration was able to affect the DNA integrity (comet assay), while the adoption of endonucleases pointed out an oxidative cause to the damage. Regarding the chromosomal damage (ENA assay), both concentrations displayed significant effects, revealing the clastogenic and/or aneugenic properties of Mancozan®. Furthermore, the two genotoxic endpoints were significantly correlated. Overall, the results revealed a genetic hazard to fish inhabiting aquatic systems contaminated by Mancozan® and strongly recommend the development of biomonitoring and regulatory policies regarding the utilization of this agrochemical.