Metal concentrations in seaweeds from west coast of libya

Abstract EN

Seventeen seaweed species were hand picked during October 2001 from the inter-tidal zone of three study sites namely Janzour, Gargaresh and Tajura along Tripoli coast of the Mediterranean Libyan coast.

Seaweed samples were sorted, oven dried and subjected to the reflux digestion using nitric acid and hydrogen peroxide for metal analyses ( Magnesium, iron, Zinc, Lead, Nickel, Copper and Cadmium) by flame atomic absorption spectrometer.

The results of metal concentrations analyzed ranged: for Mg(3260 -27313 mg/kg dry wt), Fe (109.6 - 1328.7 mg/kg dry wt), Zn (83.02 - 493.56 mg/kg dry wt), Pb (7.277- 68.29 mg/kg dry wt), Ni (4.010 -46.544 mg/kg dry wt), Cu (2.170 -10.95 mg/kg dry wt) and Cd (1.955 - 9.6195 mg/kg dry wt), of the seaweeds studied.

The highest concentrations of Mg, Fe, Zn, Pb, Ni, Cu and Cd were observed in Jania rubens, Hypnea sp, Cystoseira sp ,Jania rubens , Halimeda tuna, Codium tomentosum and Corallina sp, respectively.

These results indicate that Jania rubens has the potential to be used as bio-monitoring species for the studied metals.

Sargassum baccularia, Ulva lactuca and Cystoseira compressa, showed higher affinity to Zn and Cd, which it could be also used for bio-monitoring activities of such metals