Histological evaluation of the liver, kidney, and testes of adult male Wistar rats exposed to heavy metals-contaminated waterways

Background: Human activities continually impact the environment negatively. Some activities are particularly linked to river pollution, and this constitutes a major problem in certain regions of Nigeria. This is a result of economic development, anthropogenic human activities, and agricultural practice that have the potential for adverse health effects. This study evaluated the effect of heavy metals acquired from the waterways on the vital organs of experimental rats. Methods: Seventy (70) adult male Wistar rats, average weighing between 150-180g, were divided into seven groups of ten animals, each selected by simple randomization. Pooled sampled water and water containing the highest average concentration of singly and combined heavy metals noted in the waterways from three geological zones in Kwara state, Nigeria, were respectively given to the Wistar rats within the treatment groups ad libitum for 65 days. The kidney, liver, and testes were harvested and processed for paraffin embedding, and the effect of the heavy metals was histologically assessed. Results: Histological staining revealed variable histopathological alterations in the kidney, liver, and testes of rats in the treatment groups in comparison to the control group. Conclusion: Increased levels of heavy metals in waterways can adversely affect the organs when used for household purposes. Activities in these water bodies must be checked by regulatory agencies, and laws to discriminate against the dumping of waste in water bodies should be enforced.