GABRIELA GEANINA VASILE, STEFANIA GHEORGHE, CORINA ENE, ECATERINA ANCA SERBAN, CATALINA STOICA TOTAL MERCURY IN FISH AND BENTHIC INVERTEBRATES COLLECTED FROM OLT RIVER, ROMANIA The paper presents an assessment study on the determination of total mercury from biological samples, using Cold-Vapour Atomic Absorption Spectrometry technique which was applied on three certified reference materials: Tuna Fish ERM-CE464, Fly ash BCR-176R and Sandy Soil ERM-CC018. Recovery rates ranged from 100 to 108.8%. The method was applied on contaminated biological real samples, respectively various fish organs (Cyprinus carpio and Carrasius gibelio) as well as two types of bivalves (Dreissena sp. and Anodonta sp.) collected from Olt River after the wastewater discharge of a chemical platform. The preliminary results showed that total Hg content was above the limit allowed by the World Health Organization (0.5 mg/kg) in muscle and spleen samples harvested from carp specimens. In benthic invertebrate specimens, the Hg content ranged from 0.19 to 0.52 mg/kg dry matter in internal organs, while Hg value in shells was below the method quantification limit.