Effect of cadmium on some biomarkers in the clam Ruditapes decussatus: metallothionein quantification using two techniques

After the contamination of Ruditapes decussatus with 100 ?g/l and 200 ?g/l of cadmium chloride during 21 days, metallothioneins (MTs), malondialdehyde (MDA) and cadmium concentrations were determined in the gills and the digestive gland. The results showed an increase of Cd, MTs and MDA concentrations in the gills and the digestive gland. No significant variations of the concentrations with sex were observed. Two techniques (polarography and colorimetry) for metallothionein quantification were compared. The results showed that the polarographic method is more sensitive than the colorimetric one.

Keywords: biomarkers, cadmium contamination, malondialdehyde, metallothioneins, Ruditapes decussates, clams, heavy metals, biomonitoring, environmental pollution