Enrichment Factors (EF) on Superficial Sediments of Santos Estuarine System, Southeasthern Brazil

The Baixada Santista, located at southeastern Brazilian coast, hosts the largest harbor of South America, it is also the third most heavily populated region in São Paulo state. Many industries and domestic sewage have been contaminating the environment with heavy metals and arsenic since industrial revolution. This has been a major concern worldwide due to its toxicity and persistence. Levels of metals (Al, Cd, Cr, Cu, Ni, Pb, Zn, Fe, Mn, Sc, V) and As were determinated on 180 samples of surface sediments, by acid digestion and quantified by ICP-OES to assess enrichment factors in order to know the anthropogenic contribution of the investigated elements. The levels of metals indicated absence of contamination, but a higher enrichment of As (approximately 9.5) near Bertioga city. Ni and Cr had values between 0.5 - 2.0, Cu and Zn between 0.6 - 4.0 and 0.9 - 7.5 for Pb. Despite As, all others metals showed higher enrichment in Santos - São Vicente Estuary, especially near Cubatão. The analysis of the enrichment factor of As indicate that these values could be due to natural processes of weathering and sedimentation, meanwhile the other metals could be from antropogenic sources, since thoses values were found near industrial area.