title: Leaching of the Neonicotinoids Thiamethoxam and Imidacloprid from Sugar Beet Seed Dressings to Subsurface Tile Drains.
abstract: Pesticide transport from seed dressings toward subsurface tile drains is still poorly understood. We monitored the neonicotinoid insecticides imidacloprid and thiamethoxam from sugar beet seed dressings in flow-proportional drainage water samples, together with spray applications of bromide and the herbicide S-metolachlor in spring and the fungicides epoxiconazole and kresoxim-methyl in summer. Event-driven, high first concentration maxima up to 2830 and 1290 ng/L for thiamethoxam and imidacloprid, respectively, were followed by an extended period of tailing and suggested preferential flow. Nevertheless, mass recoveries declined in agreement with the degradation and sorption properties collated in the groundwater ubiquity score, following the order bromide (4.9%), thiamethoxam (1.2%), imidacloprid (0.48%), kresoxim-methyl acid (0.17%), S-metolachlor (0.032%), epoxiconazole (0.013%), and kresoxim-methyl (0.003%), and indicated increased leaching from seed dressings compared to spray applications. Measured concentrations and mass recoveries indicate that subsurface tile drains contribute to surface water contamination with neonicotinoids from seed dressings.
authors.affiliation: Agroscope , Zürich, Switzerland.
authors.forename: Felix E
authors.initials: FE
authors.lastname: Wettstein
authors.affiliation: Agroscope , Wädenswil, Switzerland.
authors.forename: Roy
authors.initials: R
authors.lastname: Kasteel
authors.affiliation: Agroscope , Zürich, Switzerland.
authors.forename: Maria F
authors.initials: MF
authors.lastname: Garcia Delgado
authors.affiliation: Agroscope , Wädenswil, Switzerland.
authors.forename: Irene
authors.initials: I
authors.lastname: Hanke
authors.affiliation: Agroscope , Wädenswil, Switzerland.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Huntscha
authors.affiliation: Agroscope , Wädenswil, Switzerland.
authors.forename: Marianne E
authors.initials: ME
authors.lastname: Balmer
authors.affiliation: Agroscope , Wädenswil, Switzerland.
authors.forename: Thomas
authors.initials: T
authors.lastname: Poiger
authors.affiliation: Agroscope , Zürich, Switzerland.
authors.forename: Thomas D
authors.initials: TD
authors.lastname: Bucheli
mesh_terms: D000383:Agriculture; D027461:Beta vulgaris; D001965:Bromides / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D004784:Environmental Monitoring; D004852:Epoxy Compounds / Q000032:analysis; D060587:Groundwater / Q000737:chemistry*; D006540:Herbicides / Q000032:analysis; D007093:Imidazoles / Q000032:analysis*; D007306:Insecticides / Q000032:analysis*; D008689:Methacrylates / Q000032:analysis; D000073943:Neonicotinoids; D009574:Nitro Compounds / Q000032:analysis*; D010078:Oxazines / Q000032:analysis*; D010648:Phenylacetates / Q000032:analysis; D012639:Seeds; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants; D021241:Spectrometry, Mass, Electrospray Ionization; D000073739:Strobilurins; D000077922:Thiamethoxam; D013844:Thiazoles / Q000032:analysis*; D014230:Triazoles / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D001965:Bromides; D004852:Epoxy Compounds; D006540:Herbicides; D007093:Imidazoles; D007306:Insecticides; D008689:Methacrylates; D000073943:Neonicotinoids; D009574:Nitro Compounds; D010078:Oxazines; D010648:Phenylacetates; D012987:Soil; D012989:Soil Pollutants; D000073739:Strobilurins; D013844:Thiazoles; D014230:Triazoles; D014874:Water Pollutants, Chemical; C469328:kresoxim-methyl; C082359:imidacloprid; D000077922:Thiamethoxam; C109476:epoxiconazole
keywords: drainage water; leaching; neonicotinoids; preferential flow; seed dressing; subsurface tile drains; sugar beet