The levels and distributions of eight heavy metals in the sediments of four mangrove l areas, namely Abu Dhabi. Un1m al-Quwuin. Ras al-Khail11ah, and Khor Khuwair along the shoreline of the United Arab Emirates (U.A.E. ) were investigated. The metal levels, expressed as μg g~- l as well as organic carbon (9) in different mangrove areas were scattered i11 the ranges 3. l2--6.94 for cadmium (mean 4.82), 5.70-- l4.0 for cobalt (mean l0.2), 8.28-- l 8.9 for chromium (mean ll.9), 5.3 l- 29.4 for copper (mean 7.2l ). 28.8--l69 for manganese (mean 84. l ), l4.8--l09 for nickel (mean 36.4), l3.2M9.8 ft)r lead (mean 28. l ). 4.59--22.4 for zinc (mean l l .3), and ND-2. l3 for organic carbon (mean 0.63/100). Significant variations in the levels of these metals were considered due to : l ) organic carbon content. 2) presence of well developed mangrove forests; and 3 ) anthropogenic inputs such as discarded automobiles, transtformers, batteries, tires and spilled crude oil. atmospheric fallout as well as waste--waters disposal. In addition recreational activities cause negative effects. Concentrations of manganese, nickel and lead were significantly higher than the other metals. The high concentrations of Mn and Ni were due to non-anthropogenic sources (the geological nature formations and the presence of high mountains of basic igneous rocks), whereas the high levels of 1ead were due to inputs from oil spills. discarded solid wastes such as automobiles, batteries and the prior high rate of petrol combustion lead. Significant relationships were observed between several couples of metals in different mangrove regions.
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