CLINICAL EVALUATION AND MORTALITY OF LAMBARIS SUBMITTED TO DIFFERENT RESIDUAL CONCENTRATIONS OF TRICLOSAN IN WATER (Atena Editora)

Abstract

Triclosan is a broad-spectrum antimicrobial that has activities against gram positive and gram negative bacteria, fungi and viruses, being used in formulations of personal hygiene products such as toothpastes, shampoos and soaps. Studies demonstrate its presence in urban and industrial effluents and report the detection of residues in surface waters and sediments from freshwater environments. The objective of this study is to evaluate the effect of residual concentrations of triclosan in yellowtail lambaris (Astyanax altiparanae), through the physiological response, such as clinical signs and mortality. Two tests were carried out,the first in concentrations of 5mg/L, 10mg/L, 15mg/L, 25mg/L and two controls. In the second assay, concentrations of 4mg/L, 3mg/L, 2mg/L, 1mg/L, 0.5 mg/L and two controls were used. In both, each fish was considered as a sampling unit with three replications. In the first trial, all fish exposed to triclosan died within 30 minutes. In the second trial, the fish showed clinical signs of intoxication and mortalities between 4h and 24h at the highest concentrations and, at the concentration of 0.5 mg/L, they remained alive for 96 h without any clinical change. Thus, the range between 1mg/L and 0.5mg/L was established as a reference for sublethal experiments. The clinical signs observed wereneurological, such as erratic swimming and spinning, culminating in the death of fish; in addition to clinical signs of hemorrhage, mainly in the gills. With the results obtained, it is concluded that the lambaris resulting from acute exposure to triclosan showed compromised health with clinical signs of intoxication and high mortality.