Acute effects of sodium dodecyl sulphate on the survival and on morpho-histochemical characteristics of the trunk kidney of juvenile turbot Scophthalmus maximus L.

The present article reports the effect on survival as well as on the morpho-histochemical changes in the trunk kidney of juvenile turbot Scophthalmus maximus, L. induced by acute action of the anionic surfactant, sodium dodecyl sulphate (SDS). The LC50 of SDS at 96 hours was found to be 7.5 mg/l. Lots of 20 juvenile turbots were exposed to SDS concentrations of 3, 5, 7 and 10 mg/l: the exposure time required for 50% mortality of the specimens was 384,190,12 and 4 hours and surface tension values were 60.2, 56, 54.9, and 53.3 mN/m, respectively. It should be mentioned that there was a relatively high resistance to SDS of turbot compared to other teleost species, which may be related to its benthic habit. Histopathological lesions and histochemical changes that appeared in the trunk kidney of specimens exposed to the concentrations mentioned were examined. The abnormalities observed in this organ included vacuolation and desquamation of epithelial cells and degeneration of glomeruli and tubules. At the histochemical level, we appreciated some changes in the normal distribution of carbohydrates and proteins. Although the precise mechanism by which the renal tissue injury occurs is unknown, the function of this vital organ was seriously affected and this fact may ultimately play an important role in the mortality of turbots exposed to SDS.