Monitoring of Pesticide Residues in Surface and Subsurface Waters, Sediments, and Fish in Center-Pivot Irrigation Areas

In this study, the monitoring of pesticide residues, which show potential for environmental contamination, in center-pivot irrigated areas in the Brazilian cerrado, was performed. The pesticides monitored were acephate, atrazine, azoxystrobin, buprofezin, carbofuran, cyproconazole, chlorpyrifos, difenoconazole, diuron, imidacloprid, malathion, methamidophos, metolachlor, metribuzin, monocrotophos, monuron, thiamethoxam, and triazophos. Surface water samples were collected upstream and downstream of Tijunqueiro dam. The subsurface water in piezometric wells was drilled in the surroundings of the irrigated area; fish and sediment were collected in the dam. The technique of solid phase extraction (SPE) was used for the extraction of water samples, the matrix solid phase dispersion (MSPD) for the sediment samples and QuEChERS (quick, easy, cheap, effective, rugged and safe) for the fish samples. The multiresidue methods used were accurate and precise for most pesticides monitored by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Atrazine was detected in two of the subsurface water samples.