Effects of temperature and salinity on the toxicity of cypermethrin on the liver tissue of zebra fish(Aphanius sophiae)

The toxicity of cypermethrin at 0.02 μg L-1 concentration in relation to salinity (0 and 14 ppt) and temperature (16±1 and 25 ± 1°C) was studied on the liver tissue of zebra fish (Aphanius sophiae) exposed to cypermethrin for 14 days under labratory condition. The liver tissue changed significantly with changes in salinity and temperature. The major changes were overlapped hepatocytes, nucleous irregularity, cloudy swelling, atrophy, fat degeneration, pyknosis, focal necrosis, karyolysis, accumulation of kupffer cell, necrosis and bile stagnation. The results showed that sensitivity to cypermethrin increased with decrease in salinity and increase in temperature.This fish is, therefore, not a suitable indicator for cypermethrin assessment in aquatic ecosystems, and if considered as an indicator, the temperature and salinity should also be considered.