Acute toxicity assessment of Di-ammonium phosphate LC₅₀ for 96 hrs in Channa punctatus (Bloch.)

Abstract

The unregulated use of chemical fertilizers such as Di-ammonium Phosphate (DAP) in agriculture has raised serious environmental concerns due to their runoff into aquatic ecosystems. This study evaluates the acute toxicity of DAP on Channa punctatus (Bloch), a freshwater fish commonly found in Indian water bodies. Fish were exposed to various concentrations of DAP (1-16 g/L) under controlled laboratory conditions, and mortality was observed over a 96-hour period. Behavioural and physical symptoms such as erratic swimming, excessive mucus secretion, and loss of equilibrium were also monitored. Probit statistical analysis revealed a 96-hour LC?? value of 4 g/L, indicating moderate toxicity. The results demonstrate that even short-term exposure to DAP at elevated concentrations can be lethal to aquatic organisms. These findings highlight the need for stricter regulation and responsible management of fertilizer application to minimize ecological damage to freshwater ecosystems.