Vol. 3, Issue 2, Part B (2017)

Abstract
Triclosan, an antiseptic agent, ubiquitous in the pharmaceuticals and personal care products have the ability to enter into the aquatic ecosystems that pose a great threat to the dwelling organisms. The present study was aimed to assess the genotoxic and haematological consequence of triclosan in the fish, Oreochromis niloticus. Fish was exposed to triclosan at one-fifth (562 µg/ L) and one-tenth (281 µg/ L) of LC₅₀ concentrations for 24, 72 and 96 h maintaining the control group. Triclosan treatment at sublethal concentrations significantly reduced the serum protein and this may be due to increased proteolytic activity and decreased anabolic activity of protein. Exposure to triclosan at both concentrations decreased RBC and haemoglobin and this could be due to haemolysing capacity of triclosan and rapid oxidation of haemoglobin to methaemoglobin. However, WBC content was significantly increased owing to leucocyte mobilization, as the defensive mechanism of fish to overcome treatment-related stress. Genotoxic effects of triclosan are revealed by the nuclear abnormalities as formation of micronucleus, and also lobed, blebbed, notched, irregular and apoptotic nucleus. The present observation was the first study to prove that triclosan induces genotoxicity and also influenced the haematological changes in the fish, Oreochromis niloticus.