Acute arsenic exposure induces cyto-genotoxicity and histological alterations in Labeo rohita.

Abstract

Background: Arsenic emerges as most potent hazardous element ranked as number one in ATSDR (Agency for Toxic Substances and Disease Registry) list, can easily accumulate in fish, transported to humans via consumption and affect humans and aquatic organisms. Considering above, current experiment designed to evaluate cyto-genotoxicity and histological alterations induced by arsenic in Labeo rohita used as an animal model.

Methods: By applying complete randomized design sampling acclimatized individuals of Labeo rohita (10 batches of 10 each with triplicates) were exposed to nine definitive doses (12, 14, 16, 18, 20, 22, 24, 26 and 28 mgL^-1) of arsenic in glass aquaria to determine 96-h lethal concentration (LC₅₀) of arsenic. Control group without arsenic was also run simultaneously. After 96-h exposure various histo-biochemical parameters were evaluated in all experimental groups.

Results: The 96-h lethal concentration of arsenic was found to be 20.2 mgL^-1. Upon arsenic exposure, oxidative stress biomakers: catalase (CAT), superoxide dismutase (SOD) and lipid per oxidation (LPO) and accumulation of arsenic in all targeted organs were considerably (p ≤ 0.05) increased in dose dependent manner and in comparison, to unexposed (control) group. Serum liver function enzymes, immunological status (albumin, globulin and total protein), cortisol level and cytochrome P450 gene expression remarkably (p ≤ 0.05) altered on arsenic exposure. The histological analysis also showed destructive alterations on exposure to arsenic in gill and liver tissues.

Conclusion: These results confirmed that exposure of arsenic led to pronounced deleterious alterations in Labeo rohita and evidencing the need for monitoring alarmingly increasing concentration of arsenic.