THE CORRELATIONS BETWEEN MERCURY SPECIATION AND DISSOLVED ORGANIC MATTER IN THE SEDIMENT OF THE RED SEA

This study addresses the correlations between Hg an d organic matter in recent sediment; samples were collected from the Gulf of Aqaba, Red Sea coasts (o ligotrophic regions) during 2010. In the present st udy TOC analyzer was used to determine Total Organic Carbon (TOC) and Total Nitrogen (TN) concentrations and the total amount of mercury (Hg T) in sediment samples were analyzed by Hydra-C mercury analyzer. The obtained results indicated that, mercury, TOC a nd TN average concentrations in the Red Sea were 85.42 ng g -1 , 5.10 and 4.45 mg L -1 , respectively. The results show that the Total Org anic Carbon (TOC) in sediment represents the sum of various organic comp ounds, which may play a completely different role i n the distribution and accumulation of Hg. slightly c orrelations between the TOC and the concentration o f Hg in the studied sediment arise mainly from the labil e portion of organic matter released. These compoun ds primarily consist of easily degradable algal-derive d lipids and various pigments, which are petrograph ically described as a soluble Organic Matter (OM). The preserved OM in sediment is commonly entrapped within the cell walls of phytoplankton and also appears as a surface coating on sediment particles. The stron g affinity between Hg and OM is due not only to its c hemical reactivity, but also to the physical charac teristic of these labile compounds, which plays the most imp ortant role in the distribution of Hg in sediment.