Abstract

TOXICITY OF 2, 4-DICHLOROPHENOXYACETIC ACID ON FRESHWATER FINGERLINGS LABEO ROHITA (HAMILTON)

*Arivu, I., Muniyan, M., Muthulingam, M., Parthiban, P., Ambedkar, G., Kamalkanth, S.

ABSTRACT

2,4-dichlorophenoxyacetic acid (2,4-D) is an herbicide commonly used in agriculture. The residues of 2,4-D is present in air, water, soil and edibles. It constitutes a real hazard for human and animal health as numerous accidents of poisoning deaths caused by this herbicide have been reported. The point of view concerning acute and sub-lethal toxicity of herbicide 2,4-D to fingerlings of Labeo rohita of mean weight of 6-8 g and standard length of 8-10 cm were investigated under laboratory condition. In 96 hours, LC50 was 300 ppm the toxicant lead to initial increase in the opercula ventilation rate which then decreased below the status by the end of the 96 hours. Restlessness, immobilization, loss of balance and air gulping impaired equilibrium, erratic swimming, changes in orientation locomotion and convulsion were commonly observed before death during the acute bioassay. Exposed cells of the fish gill had coagulation necrosis of the lamellae, per lamellae fibrosis and inflammations. The results from this study revealed that 2,4-D was very toxic to finger lings of Labeo rohita under laboratory condition and its application should therefore, be restricted in the field.

Keywords: 2, 4-D, Fingerlings of Labeo rohita, acute toxicity, Behavioral studies.