Benthic foraminifera as bioindicators of anthropogenic pollution in the Red Sea Coast, Saudi Arabia

The concentrations of Fe, Mn, Cu, Ni, Zn, Pb, Cr, Co, and Cd were measured in the tests of two foraminiferal species (Sorites orbibulus and Peneroplis planatus) using ICP-MS to assess the marine contamination. Iron was the most abundant metal (3294 μg/g), followed by Mn (133 μg/g), Cu (34.7 μg/g), Zn (28.3 μg/g), Cr (25 μg/g), Ni (18.9 μg/g), Pb (12.2 μg/g), Co (9.5 μg/g), and Cd (0.85 μg/g). The values enrichment factor, geo-accumulation index, and contamination factor show that the foraminiferal shells are enriched in (Cd, Cu, Pb) posing an ecological risk. Iron shows highest concentration amongst the heavy metals recorded in the study shells, however, shows low concentration in comparison with surrounding areas of Red Sea coast in Saudi Arabia and Egypt. Other heavy metals show higher concentrations than those recorded in Egypt and Saudi Arabia. The elevated heavy metal concentrations in the foraminiferal tests may be attributed to the industrial and urban activities along Yanbu coast.