Scholarly Article
Health Risk Assessment and Levels of Toxic Heavy Metals in Oreochromis niloticusand Clarias gariepinusfrom Alwero and Abay River Basin
Massresha, Erkihun, Zewdu, Ashagrie, Mateos, Hintsa, Lewandowski, Paul
2025-03-24 · Jefore Ethiopian Journal of Applied Sciences · Wolkite University
Abstract
This study investigated concentrations of toxic heavy metals (Cr, Pb, Hg, Sn, As, Co, Cd) in the muscle and gill tissues of Oreochromis niloticus and Clarias gariepinus from Ethiopia's Alwero and Abay Rivers, alongside the associated human health risks. Eighty fish samples (20 per species per river) were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES). Metal accumulation was significantly higher in gills than in muscle across species and sites (p < 0.05). Muscle profiles varied by location: O. niloticusand C. gariepinusexhibited dominant Sn and Asconcentrations in the Alwero and Abay Rivers, respectively.Notably, while target hazard quotient (THQ) and hazard index (HI) values remained below 1, indicating no significant non-carcinogenic risk, the carcinogenic risk (CR) for inorganic arsenic in C. gariepinus from the Abay River (1.36 × 10⁻⁴) exceeded the acceptable threshold of 10⁻⁴. Furthermore, chromium, lead, and arsenic levels in the Abay River frequently exceeded global safety limits established by the European Commission and the FAO/WHO. Conversely, fish from the Alwero River generally fell within safe consumption limits, despite elevated tin levels in gills. The identified toxicological hazards highlight a critical inflection point for Ethiopian fisheries management. Integrating stringent effluent standards with continuous bio-sentinel monitoring is essential to mitigate the long-term oncogenic risks associated with the consumption of O. niloticus and C. gariepinus from these vulnerable riverine catchments.
Keywords
Heavy metal, Health Risk Assessment, O. niloticus, C. gariepinus, Abay River, Alwero River
Citation Details
Jefore Ethiopian Journal of Applied Sciences, pp. 137-156