Assessment of heavy metal (Cu, Ni, Fe, Co, Mn, Cr, Zn) pollution in effluent dominated rivulet water and their effect on glycogen metabolism and histology of Mastacembelus armatus

Abstract

The present study was conducted to examine the contamination of rivulet situated at Kasimpur, Aligarh (27.218° N; 79.378° E). It receives the wastewater of Harduaganj Thermal Power Plant (HTPS) containing fly ash and heavy metals. Among the heavy metals estimated in the rivulet water, Fe (8.71 mgL(-1)) was present in the highest concentration followed by Cu (0.86 mgL(-1)), Zn (0.30 mgL(-1)) Mn (0.21 mgL(-1)), Ni (0.12 mgL(-1)), Co (0.11 mgL(-1)) and Cr (0.10 mgL(-1)). The values for the heavy metals such as Fe, Ni and Mn were beyond the limits set by UNEPGEMS. Bioaccumulation of these heavy metals was detected in tissues such as gills, liver, kidney, muscle and integument of the fish Mastacembelus armatus. Accumulation of Fe (213.29 - 2601.49 mgkg(-1).dw) was highest in all the organs. Liver was the most influenced organ and integument had the least metal load. The accumulation of Fe, Zn, Cu and Mn, observed in the tissues were above the values recommended by FAO/WHO. Biochemical estimation related to blood glucose, liver and muscle glycogen conducted showed significant (p < 0.01) elevation in blood glucose content over control (17.73%), whereas liver glycogen dropped significantly (p < 0.01) over control (-89.83%), and similarly muscle glycogen also decreased significantly (p < 0.05) over control (-71.95%), suggesting enhanced glycolytic capacity to fuel hepatic metabolism. Histopathological alterations were also observed in selected organs (gills, liver and kidney) of Mastacembelus armatus.

Keywords: Bioaccumulation; Glycogen; Heavy metals; Histopathology; Liver; Mastacembelus armatus.

Figure 1

Map showing the location of Harduaganj Reservoir (27.218° N and 79.378° E) which receives the effluents from the Power Plant via pipes.

Figure 2

a) Harduaganj Thermal Power Plant draining wastewater into the reservoir b) Present Scenario: Degraded condition of reservoir.

Figure 3

a) Show wastewater emerging from Power Plant polluting the rivulet b) Rivulet water used for different Purposes.

Figure 4

a) Gills of control Mastacembelus armatus show normal structure of lamellae, erythrocyte (E), nucleus of epithelial cell (NE), pillar cell (PC), secondary lamellae (SL) 400X; Figure b, c and d) Gills of exposed Mastacembelus armatus showing b) complete lamellar fusion (Lfu) coupled with hyperplasia (H) 200X; c) Shrinked lamella (SHL), swelling of lamella (SWL), deformed lamella (DL), curved lamella (CL) 400X; d) Lamellar fusion (Lfu), hyperplasia (HP), necrosis (N), Hypertrophy (HT), epithelial lifting (EL), Lamellae shrinkage (L Shrinkage), Stained with Hematoxylin and Eosin.

Figure 5

a) Show control liver of Mastacembelus armatus having hepatocytes (H) with normal nucleus (N), bile duct is also present 400X; Figure b and c) Show liver of exposed Mastacembelus armatus ; b) Congestion of blood vessel (C), necrosis (N) and vacuolization (V) of hepatocytes 200X; c) Pyknotic nuclei (PN), infiltration of leucocytes (LI), degeneration of arteriole (DA) and necrosis of parenchyma (N) 400X. Stained with Hematoxylin and Eosin.

Figure 6

a) Show control kidney of Mastacembelus armatus having normal structure glomeruli (G) with bowman's capsule (BC), renal tubules (RT) and hematopoeitic tissues (HPT) 400X; Figure b and c) Show kidney of exposed Mastacembelus armatus b) Vacuolization of tubules (V), hyperplasia of glomeruli (GHY) and have no bowman's space (NBS), necrosis of renal tubule (NT) 200X; c) Lumen of tubule dilated (DL), necrosis of hematopoeitic tissue and tubule (N), hypertrophy of tubule (HT) due to which lumen is reduced (RL) 400X; Stained with hematoxylin and eosin.