Removal of epoxiconazole and pyraclostrobin from highly contaminated effluent (grams per liter level): Comparison between ozone and solar still decontamination using real field conditions

Sci Total Environ. 2019 Feb 25:653:597-604. doi: 10.1016/j.scitotenv.2018.11.043. Epub 2018 Nov 5.

Abstract

Brazilian environmental legislation obliges the aeroagriculture operators to treat the effluents generated after aircraft washing. This effluent commonly contains high levels of pesticides (g L-1) with potential to produce point source pollution. In the present study, we evaluated the efficiency of two systems on the removal of the fungicides epoxiconazole and pyraclostrobin from these effluents. The first system is based on ozonation and is currently suggested by regulatory authority. The second system is based on a pyramid-shaped solar still. The pesticides removal was monitored using liquid chromatography mass spectrometry to determine the mass quantity of both molecules throughout the treatment. After treatment with ozone treatment, the total mass of epoxiconazole decreased by 73% and pyraclostrobin decreased by 90.8%. The solar distillation system removed epoxiconazole and pyraclostrobin by >99.995 and 99.99%, respectively. The both systems proved to be efficient in the treatment of effluent containing residues of the fungicide Opera®, a formulation containing epoxiconazole and pyraclostrobin. The solar distillation system showed a higher degree of removal and presents the advantage of operating without energy sources, reagents or consumables.

Keywords: Advanced oxidation processes; LC-MS/MS; Pesticides remediation; Transformation products; Water treatment.