Anthropogenic source assessment of Ra-226 and Pb-210 in a sediment core from the Cubato River estuary (SE Brazil)

Author(s)

Sanders, L. M. ^[1] ; Sanders, C. J. ^[2] ; Luiz-Silva, W. ^[3] ; Machado, W. ^[2] ; Silva-Filho, E. V. ^[2] ; Patchineelam, S. R. ^[2]

Affiliation

^[1] IRD, BR-22780 Rio De Janeiro - Brazil

^[2] Univ Fed Fluminense, Dept Geoquim, Inst Quim, BR-24020007 Niteroi, RJ - Brazil

^[3] Univ Estadual Campinas, Inst Geociencias, BR-13083970 Campinas, SP - Brazil

• Document type: Journal article
• Source: JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY; v. 287, n. 3, p. 729-732, MAR 2011.
• Web of Science Citations: 4

Abstract

A sediment core from an estuarine area receiving drainage from the highly industrialized Cubato River basin (SE Brazil) showed (226)Ra and (210)Pb activities up to 80 and 213 Bq kg(-1), respectively, which are greater than activities considered as regional background levels. Radionuclides and the elevated phosphorus concentrations (up to 0.3% sediment dry weight) found along the sediment core were significantly correlated with each other, indicating source similarity. These results indicate that (226)Ra and (210)Pb activities are affected by fertilizer industry-derived inputs in addition to natural sources. This interpretation was supported by (210)Pb/(226)Ra ratios (found to be between 2.6 and 3.9) that indicate disequilibrium between (226)Ra and its decay product (210)Pb, as expected for phosphogypsum-affected sediments. (AU)

• FAPESP's process: 08/11511-8 - Chemical and physical factors as environmental diagnosis of an impacted tropical estuary by trace-elements: a holistic investigation (sediment, water and biota) in the Santos-Cubatão estuarine system (São Paulo State, Brazil)
• Grantee: Wanilson Luiz Silva
• Support Opportunities: Regular Research Grants