Effects of electronic waste on cytogenetic and physiological changes in snakehead fish (Channa striata)

The objectives of this study were to investigate cadmium (Cd), chromium (Cr), and lead (Pb) concentrations in water and sediment as well as the muscle, gill, and liver of snakehead fish (Channa striata) and to reveal chromosomal aberrations, changes in serum biochemical parameters, and histopathological alterations of fish from a reservoir near an electronic waste dumping area. Cd, Cr, and Pb concentrations were determined using inductively coupled plasma optical emission spectrometry. Chromosomal aberrations were studied in kidney cells using a conventional technique. The biochemical parameters were measured using an automated analyzer, and histopathological photographs were obtained using a transmission electron microscope. The results showed that heavy-metal concentrations in water and sediment did not exceed the standards, whereas Cd and Pb concentrations in the gill and liver exceeded the standards. The accumulation pattern of heavy metals in organ tissues was exhibited according to the following order: gill > liver > muscle. Five types of chromosomal aberrations were a centromere gap, single chromatid break, deletion, single chromatid gap, and fragmentation. The average percentages of chromosomal aberrations in polluted and reference C. striata were 4.60% and 1.00%, respectively. The statistical analyses of chromosomal aberration and biochemical parameters indicated that total protein, aspartate aminotransferase, and alanine aminotransferase significantly differed between the polluted and reference C. striata (p < 0.05). The liver histopathological alterations revealed atypical cellular structures, such as vacuolar appearance, nucleus degeneration, rough endoplasmic reticulum disintegration, abnormal cytoplasmic mitochondria, and deposition of heavy metals. Heavy-metal contaminations from electronic waste dumping areas affect fish in terms of chromosomal aberration, serum biochemistry, and histopathology.