Concentration of arsenic in water, sediments and fish species from naturally contaminated rivers

JUAN JOSE ROSSO; NAHUEL FRANCISCO SCHENONE; ALEJO PÉREZ CARRERA; ALICIA FERNÁNDEZ CIRELLI

Buenos Aires

Taller; 1º Taller ?El Arsénico como factor limitante en la producción agrícolo-ganadera; 2011

Centro de Estudios Transdisciplinarios del Agua, FVet, UBA.

Arsenic (As) is a highly ubiquitous and potentially toxic element. It may occur in surface freshwater ecosystems as a consequence of both natural contamination and anthropogenic activities. Human exposure to As can occur through a variety of routes, although the consumption of groundwater is the main route of exposure for most people. Health problems because of the presence of As in groundwater have been recognised in many parts of the world. Dietary intake may also be important. The US Food and Drug Administration (1993) indicated that fish and other seafood account for 90% of the total food As exposure with all other foods accounting for the remaining 10%.Arsenic has been classified as a human carcinogen by the U.S. Environmental and Protection Agency (USEPA 1997) and the International Association for Research on Cancer (IARC 1987). More recently, As was ranked first on the Superfund List of Hazardous Substances (ATSDR 2007). In Argentina, people exposed to high level of As in drinking water develop an endemic disease known as Regional Endemic Chronic Hydroarsenism (HACRE). The Chaco-Pampa Plain is one of the largest regions in the world (ca. One million km2) with the presence of As in groundwater (Smedley and Kinniburg 2002). The geographic distribution of arsenic and trace elements in lotic ecosystems of this region was already evaluated. These authors revealed that natural pollution by As is a regional problem in surface drainages. Nevertheless, results reporting the level of arsenic pollution in sediments and biota of freshwater ecosystems are scarce.