Cytogenetic, Serum Liver Enzymes and Liver Cell Pathology of the Hampala Barb Fish (Hampala macrolepidota) Affected by Toxic Elements in the Contaminated Nam Kok River near the Sepon Gold-Copper Mine, Lao PDR

Abstract

This study aimed to determine toxic element concentrations in aquatic environments, including water and sediment, and in the Hampala macrolepidota fish, and to evaluate chromosome abnormalities, serum liver enzyme changes and liver histopathological alterations in H. macrolepidota from the Nam Kok River near the Sepon gold–copper mine, Lao People’s Democratic Republic, as compared with a control area without mining activity. The results revealed significant differences (p < 0.05) in As, Ba, Cu, Fe, Mn, Ni, Se and Zn in water, in all of the studied potentially toxic elements in sediment, and in As, Ba, Cd, Cr, Cu, Mn, Ni, Se, and Zn in the fish between the study and control areas. A chromosome assessment demonstrated 6 types of chromosome abnormalities, among which centric gap had the highest total number of chromosome abnormalities. Percentage of chromosome abnormalities, percentage of cells with chromosome abnormalities and serum liver enzymes in H. macrolepidota were significantly different (p < 0.05) between the two studied areas and were higher in the contaminated fish than in the control fish. The observation of liver histopathological changes revealed cellular degeneration, such as nuclear damage, abnormal cytoplasmic mitochondria and the disintegration of rough endoplasmic reticulum. The results indicate that the contamination of potentially toxic elements in the Nam Kok River near the Sepon gold–copper mine area negatively affected chromosomes, serum liver enzymes and liver cell structures in H. macrolepidota.

Heavy Metals and Metalloid Effects on Cytogenetics in Frogs (Sylvirana nigrovittata) around the Sepon Gold-Copper Mine, Lao PDR

“…They are scientifically accepted as good indicators for toxicant or polluted-substance contamination and accumulation in aquatic ecosystems (Tengjaroenkul et al, 2018). Soulivongsa et al (2020Soulivongsa et al ( , 2021 reported cytotoxicity as chromosome aberrations of heavy metals in two fish species (Osteochilus vattatus and Hampala macrolepidota) from the Nam Kok River near the Sepon gold-copper mine area, Lao PDR. However, information related to chromosomal studies of amphibians near the Sepon gold-copper mine with regard to heavy metal point sources is very limited.…”

A Comparative Study on the Haematological and Biochemical Alterations in Catfish (Clarias gariepinus) under Natural and Artificial Environments in Sokoto Metropolis, Nigeria

“…Similarly, the examination of serum constituents has produced valuable information for detection and diagnosis of metabolic disturbances and diseases in fish [7]. In particular, a number of liver injury biomarkers have often been used to detect unhealthy state in fish [10].…”