Assessment of the impact of agriculture on environmental preservation areas of the Ribeira de Iguape River, Sao Paulo

In order to ascertain the impact of agricultural activities on water quality of the Ribeira de Iguape River Basin in the state of Sao Paulo, surface water areas for catchment and drinking water have been characterized. The sampling period covered March/2002 - February/2003 and January/2004 at 10 different catchment points. SPE-LC-UV/Vis was used to monitor various pesticide classes such as carbamates, triazines and nitroamlines. The results revealed that water quality is associated with seasonal variation. Of 152 samples analyzed, only 24% showed the presence of pesticides, particulary during the wet season. High variability in pH, turbidity and color were observed.