ASSESSMENT OF HEAVY METALS AND HYDROCARBONS IN RHIZOPHORA MANGLE CALLINECTES SAPIDUS, & SEDIMENT IN QUA-IBOE RIVER, AKWA IBOM STATE NIGERIA

Abstract

The assessment of heavy metals and hydrocarbon contents in mangrove swamp flora and fauna in Qua-Iboe River was investigated. The sediment, Callinectes Sapidus and Rhizophora mangle in the study area were analysed for Pb, Cd, Hg, total petroleum hydrocarbon (TPH) and total hydrocarbon content (THC) in wet and dry season. Results showed that, among the metals investigated, Pb had the highest concentration in all the samples for both wet and dry seasons, ranging from 0.002 – 2.344mg/kg. THC showed a higher concentration than TPH in all the samples, ranging from 492.41 to 794,931.81 mg/kg while TPH ranged from 175.97 – 129204.54 mg/kg. Generally, pollutant concentrations were higher in the dry season than wet season and the bioaccumulative behavior of HM in the samples followed the order: sediment > Rhizophora mangle > callinectes sapidus while hydrocarbon bioaccumulation followed the order: Rhizophora mangle > callinectes sapidus > sediment. The concentration of Pb and hydrocarbon in the samples analysed were found to exceed the WHO and FEnv permissible limit, posing an environmental risk to aquatic flora and fauna.