Seasonal AVS-SEM relationship in sediments and potential bioavailability of metals in industrialized estuary, southeastern Brazil

Author(s)

Nizoli, Erico Casare ; Luiz-Silva, Wanilson

• Document type: Journal article
• Source: ENVIRONMENTAL GEOCHEMISTRY AND HEALTH; v. 34, n. 2, p. 10-pg., 2012-04-01.

Abstract

In anoxic sediments, as those found in estuaries, the mobility of metals can be controlled by the formation of stable sulfide complexes. The potential bioavailability of a metal can then be predicted on the basis of the acid volatile sulfide (AVS) and simultaneously extracted metals (SEM) criterion. Distributions of AVS and SEM (Hg, Cu, Pb, Cd, Zn, and Ni) along the sediment profiles were determined seasonally for three rivers that constitute the Santos-Cubato estuarine system (SE Brazil), which is located in one of the most industrialized areas of Latin America. AVS and SEM concentrations varied significantly, from 0.04 to 31.9 mu mol g(-1) and 0.086-6.659 mu mol g(-1), respectively. The highest AVS levels in sediments were detected in the winter, whereas high SEM values predominated in the summer. Considering SEM-AVS molar differences as a parameter to evaluate potential bioavailability, sediments nearest to the industrial area represent higher risk to biota, especially during the summer. It is due to relatively low AVS values and not necessarily high concentrations of metals. (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