Study of the distribution of dichlorobenzenes in sediment and water of Suquía River basin (Córdoba-Argentina) by an optimised SPME-GC-MS procedure

Abstract

Three dichlorobenzene isomers (DCBs) were monitored in water and sediment from the Suquía River basin by Solid Phase Microextraction (HS-SPME), coupled to Gas Chromatography-Mass Spectrometry (GC-MS). DCBs were not detected in water or sediments corresponding to the upper basin. Pollution with DCBs became evident when the river flows through small cities. As expected, Córdoba city causes the most severe pollution, presenting up to 764.7 μg kg-1 DW DCBs in the sediment of urban areas. Results show that DCBs mainly originate in domestic activities, reaching the river by non-point sources such as urban run-off or sewage discharge, resulting in a widespread distribution in the basin. The high level of DCBs found in sediments involves absorption of these xenobiotics in the natural organic matter of sediments. This organic layer could be responsible for transporting DCBs downstream from their discharge, thus spreading the pollution throughout the basin.