PESTICIDE-RESIDUES IN SURFACE WATERS OF T HE V-REGION, CHILE - PROSPECTIVE-STUDY

A study was done of seasonal variations of pesticide contents in water s of the Aconcagua river basin and Aromos dam in the V Region of Chile by solid phase extraction (SPE) and chromatographic determination wit h GC-ECD, GC-FPD and HPLC-DAD. The waters of the Aconcagua river get c ontaminated as a result of phytosanitary treatments from San Felipe to the mouth in Concon with the pesticides lindane, diazinon, oxyfluorfe n and dicofol at levels below the international standard, and with azi nphos-methyl, methabenzthiazuron, lenacil, diflubenzuron and atrazine at levels above the European standards. Waters flowing into the valley are free from pesticide as far as Los Andes. At Aromos dam atrazine c oming from Limache valley was quantified at minimum levels. The enviro nmental behaviour of these pesticides was estimated by the log P-OW in dex, the physical chemical characteristics of the waters, and regional rainfall.