Source apportionment of lead pollution in the coastal waters of Elefsis bay, Greece

• Published in: Environmental science & technology Vol. 31; no. 5; pp. 1295 - 1301
• Main Authors: Kersten, M, Garbe-Schonberg, C D, Thomsen, S, Anagnostou, C, Sioulas, A
• Format: Journal Article
• Language: English
• Published: 01.01.1997
• ISSN: 0013-936X

The isotopic ratio of lead-206 to lead-207 (IRL) was measured by inductively coupled plasma-mass spectrometry in seawater and sediment in a severely polluted bay near Athens. Enrichment factors of total lead were assessed by comparison with unpolluted sediments of defined grain sizes, with all results normalized to aluminium. The IRL values were significantly lower than those of local background or industrial sources and were influenced by the IRL of lead in petrol, a value of 1.06. Lead pollution of sediments was dominated, to the extent of 70-80 per cent, by industrial sources resulting in enrichment factors up to 18. However, about 70 per cent of dissolved lead arose in petrol. IRL values in seawater indicated the Athens sewage outfall and surface runoff from greater Athens as the primary source rather than direct atmospheric deposition. The isotope pattern in sequential extractions of sediments suggested that the petrol-derived lead fraction accumulated by precipitation with sulphide at about 2 mg per m2.year during summer anoxia. This fraction did not remobilize upon the winter breakdown of the pycnocline and reoxidation of the sediment-water interface. There are 31 references.