Investigating the Acute Toxic Effects of Urea Fertilizer on Juvenile Nile Tilapia (Oreochromis niloticus)
George, U. U. *
Department of Fisheries and Aquaculture, Faculty of Agriculture, Akwa Ibom State University, Obio Akpa Campus, Akwa Ibom State, Nigeria.
Essien-Ibok, M. A.
Department of Fisheries and Aquatic Environmental Management, University of Uyo, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
The research aimed to assess the acute toxicity of urea fertilizer on juveniles of Oreochromis niloticus. The findings indicated a correlation between increasing concentrations of urea fertilizer and higher mortality rates among the test organisms, with an LC50 value determined at 500 mg/l. Additionally, a rise in total dissolved solids was observed with higher concentrations of urea. Parameters such as temperature, electrical conductivity, dissolved oxygen and pH showed statistically significant (P < 0.05) changes as the concentrations of urea increases. Behavioural responses during the exposure phase included heightened excitability, vigorous swimming behaviours, loss of equilibrium, culminating in mortality. These results unequivocally demonstrate that urea fertilizer at acute concentrations poses significant toxic risks to juvenile Oreochromis niloticus.
Keywords: Acute toxicity, urea, juveniles, organic fertilizer, Oreochromis niloticus, agricultural productivity