Histopathology of the Tissue of a Tubificid Worm Limnodrilus hoffmeisteri Exposed to Cadmium

Abstract

Although cadmium is not an essential element for any organism, oligocheates - especially Tubificid worms - accumulate large concentrations of cadmium like other freshwater specimens. In addition, some species such as the ones that belong to Limnodrilus genera use indicator organisms. The aim of this study is to examine histopathological alterations induced experimentally by cadmium in tubificid worms (Limnodrilus hoffmeisteri) exposed for different times, and at different concentrations, and these were compared to controls. Live specimens were collected at 3 sampling sites from the Porsuk River. Samples were exposed to the contaminant for short periods of 6, 12, 24, 48 and 72 h at two different concentrations of 0.25 and 0.5 mg/L. Samples were embedded in paraffin blocks and were cut at 5 µm on a microtome. All sections were stained using Hematoxylin & Eosin. Our results showed no alterations (6, 12, 24, 48 h) compared with controls. However, after exposure for 72 h. results showed different alterations.

Keywords

• Heavy metal,cadmium,histopathology,oligochaeta

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