Determination of bioaccumulation and microscopic survey of LAS pollutant effect on the liver, kidney and gill tissues of Rutilus frisii kutum in Caspian sea

Linear alkylbenzene sulfonate (LAS) are widely used in detergent industry. Dueto contaminants entering the water, and the effects of their accumulation in fish,LAS, has a great importance in environmental pollution. In the present study,accumulation of LAS and its histological effects on gill tissue, liver and kidneyof Caspian kutum (Rutilus frisii kutum) were studied. Caspian kutum is the mostimportant and most valuable teleosts of the Caspian Sea. Due to releasingCaspian Kutum in rivers and Anzali Lagoon and unlimited entry of wastewaterto the aquatic ecosystem, research on the impact of LAS on Caspian kutum isimportant. In the present study, fish exposed to sublethal concentrations of LAS(0.58, 1.16 and 2.32 mg/l) for 192 hours. Control treatments with threereplicates at 0, 24, 48, 72, 96 and 192 hours were done. For assessments of thehistological effects of LAS, tissue sections prepared and by using Hematoxylin -Eosin were stained, then the prepared sections, examined by light microscopy.For determination of the bio accumulation of LAS, the soxhlet extraction andsolid phase extraction was performed to determine the amount of LAS usingHPLC with fluorescence detector.According to results average of bioconcentration factor and LAS concentrationsin fish had reached stable levels after approximately 72 h and thus representedsteady state BCF values in this species.The value of steady-state bio-concentration factor of total LAS was 33.96 L.Kg-1 and for each of the homologous C10-n-LAS, C11-n-LAS, C12-n-LAS and C13-n-LAS were 3.84, 6.15, 8.58 and 15.57 L.Kg-1 respectively.According to the results obtained in gills exposed to LAS, histopathologicalalteration include hypertrophy, lifting of lamella epithelium, edema, clubbing oflamellae hyperplasia, lamellar fusion and aneurysm were seen. In liver tissueexposed to three concentrations of LAS, congestion and dilation of sinusoids,irregular-shaped nuclei and degeneration in the hepatocyte, vacuolardegeneration and necrosis were observed. In kidney exposed to threeconcentrations of LAS, reduction of the interstitial haematopoietic tissue,degeneration in the epithelial cells of renal tubule, tubular degeneration,necrosis, shrinkage and luminal occlusion were observed. According to theresults the most alteration due to exposure to LAS was seen in the gill tissue.None of the control samples showed histological effects of LAS.

PhD

Advisors:Shahla Jamili,Nader Shabanipour Counsellors: Ali mashinchian Moradi, Shahab Shariati