Acute Toxicity of Fingerlings of Clarias gariepinus exposed to Glyphosate and 2, 4 ichlorophenoxyacetic acid
- October 2, 2019
- Posted by: RSIS
- Categories: Biotechnology, IJRSI
International Journal of Research and Scientific Innovation (IJRSI) | Volume VI, Issue IX, September 2019 | ISSN 2321–2705
Alozie, S. N., Ezeji, E. U.*
Department of Biotechnology, Federal University of Technology, P.M.B. 1526, Owerri, Nigeria
*Corresponding Author
Abstract— The acute toxicity effect of the exposure of glyphosate and 2, 4-dichlorophenoxyacetic acid on catfish fingerlings was evaluated using Lorke’s method. The acute lethal study of glyphosate and 2, 4-D on catfish fingerlings showed that no animal died within 24 hours. But for the mixture of glyphosate and 2, 4-D, at higher concentrations, death occurred. So, the LD50 was less than 2500mg/kg (2154.07mg/kg). The physicochemical parameters of water recorded were within the permissive limits fixed by WHO which are 6.5 and 6.5- 8.0 for dissolved oxygen and pH respectively. Although the presence of herbicides caused some changes in the quality of water in and around sprayed areas and decrease the dissolved oxygen in water, along with an increase in temperature, which may pose a threat to the survival of fish species, the results of the present study indicates that application does not result in significant changes in the physicochemical parameters to a point that is capable of causing visually observable deleterious effects in fish. This is probably because the concentrations studied here are of lower magnitude compared to those applied in agricultural practices. Also, several abnormal behaviours such as restlessness, erratic swimming, air gulping, respiratory distress, loss of equilibrium, and resting motionless at the bottom of the bowl (for those exposed to the mixture of glyphosate and 2, 4-D) were observed at higher concentrations of the toxicants. These results show that glyphosate and 2, 4-D may not have lethal effects on the fingerlings of Clariasgariepinus, but the mixture, at higher concentrations (≥2900mg/kg) may cause death. Hence, the use of glyphosate and 2, 4-D herbicides in agricultural farms should be monitored to avoid continuous leaching into water bodies.
Keywords— Clarias gariepinus, acute toxicity, herbicides, glyphosate, 2,4-D.
