Accumulation of nickel by marine macroalgae from the Saudi coast of the Arabian Gulf

Author: Ali A. Al-Homaidan

Received 17 August 2007, accepted 26 November 2007.

Abstract

Nickel contamination may have an adverse impact on the fragile coastal and marine ecosystems of the Arabian Gulf. Oil pollution is a major source of this heavy metal. The nickel concentrations were measured in seawater and in 12 species of green, brown and red algae which were collected from Dammam area on the Saudi coast of the Arabian Gulf. The algal samples were cleaned, air dried and digested with concentrated nitric acid. The Ni concentrations were measured in seawater and in the aliquot samples of algae using atomic absorption spectrophotometer. High levels of Ni were found in seawater (1.26-6.73 µg L^-1) and in algal samples (7.3-57.4 µg g^-1 dry weight). The highest levels of Ni were found in the red algae Acanthophora spicifera, Hypnea cornuta and Digenia simplex, the green alga Chaetromorpha aerea and the brown alga Sargassum latifolium and these species may be used as biomonitors of Ni contamination in the Arabian Gulf region. The alerting high levels of Ni in the Gulf region must be taken seriously and integrated efforts and serious actions should be taken at once to prevent further deterioration to this invaluable area.

Key words: Nickel, concentrations, seaweeds, Arabian Gulf, Saudi Arabia.