Role of Parasitic Helminths in Bioremediating Some Heavy Metal Accumulation in the Tissues of Lethrinus mahsena

Özet

Fish take up metals from the aquatic ecosystem and accumulate it in their muscle tissues and organs. The aim of thepresent study was to determine the role of intestinal helminths in bioremediating the accumulation of some heavy metals inthe muscle tissues of the emperor fish, Lethrinu smahsena. A total of 130 fish were collected randomly from Raas Mehsen inthe Red Sea, Jeddah coast, during the period of November 2015 to May 2016. The percent of total infection in L. mahsenafish was found to be 62%. Four species of Trematoda, one cestode larva and three species of Nematoda were recorded fromthe small intestine. Element concentrations in the infected and non-infected fish and parasites were analyzed using flameatomic absorption spectrometry. Mean concentration of individual heavy metals in trematode parasites was in the order ofAs> Fe> Zn> Pb> Cu> Cd. For cestodes, it was As > Fe> Zn> Pb> Cu> Cd. While in nematodes, it was in the order of As>Fe> Zn> Pb> Cd> Cu. Most heavy metals exhibit a significant decrease in fish tissues infected with helminthes.Bioaccumulation factors indicated much higher concentrating capacity of cestode parasites than fish organs. Thereby, cestodeand nematode infections in marine fish could be considered to be a biological indicator of heavy metal pollution and at thesame time could also minimize the bioaccumulation of heavy metals in fish tissues.