Metal bioaccumulation and histological alterations in Oreochromis andersonii at Itezhi-tezhi Dam downstream of a mining area in the Central Province of Zambia

Environ Toxicol Pharmacol. 2024 Apr:107:104394. doi: 10.1016/j.etap.2024.104394. Epub 2024 Feb 19.

Abstract

The Itezhi-tezhi Dam on the Kafue River in Zambia is a major capture fishery. However, the upstream reaches of the Kafue River receive effluents from copper mines. It was unclear whether fish health in the dam is adversely affected due to the mining effluents. We investigated the health status of fish in Itezhi-tezh Dam using a histology-based fish health assessment protocol with Oreochromis andersonii as a bioindicator. Fish were sampled in the Itezhi-tezh Dam and at a reference site further upstream on the Kafue River before it enters the mining region. Metal bioaccumulation, biometric indices and histological alterations in the gills, gonads, hearts, kidneys and livers were assessed. The findings revealed significantly higher copper and selenium sediment concentrations (p = 0.02843 and p = 0.02107 respectively), bioaccumulation of copper and selenium, and increased histological alterations in the gills, kidneys and livers of fish in the Itezhi-tezhi Dam.

Keywords: Bioaccumulation; Fish health; Fish histology; Heavy metal pollution.

MeSH terms

  • Animals
  • Bioaccumulation
  • Cichlids*
  • Copper / analysis
  • Copper / toxicity
  • Environmental Monitoring / methods
  • Metals, Heavy* / analysis
  • Metals, Heavy* / toxicity
  • Selenium* / toxicity
  • Water Pollutants, Chemical* / analysis
  • Water Pollutants, Chemical* / toxicity
  • Zambia

Substances

  • Copper
  • Selenium
  • Water Pollutants, Chemical
  • Metals, Heavy