Mitglied der Helmholtz-GemeinschaftSorption and distribution of aged atrazine residuesin the drainage system of anoutdoor lysimeter experimentN. D. Jablonowski+, S. Köppchen, A. Schäffer*, P. BurauelAgrosphere - ICG-4, Forschungszentrum Jülich GmbH, D- 52425 Jülich, Germany*RWTH Aachen University - Institute for Environmental Research (Biology V), 52074 Aachen, Germany+Author for correspondence: Nicolai D. Jablonowski –n.d.jablonowski@fz-juelich.de; +49-2461-61-2696REFERENCES(1) Kegley, S.E., Hill, B.R., Orme S., Choi A.H.,PAN Pesticide Database,Pesticide Action Network, North America.http:www.pesticideinfo.org.2009.(2) U.S. Department of Agriculture; National Agricultural Statistics Service.Agricultural Chemical Usage 2003 Field Crops Summary May2004.USDA/NASS: Washington, D.C.,2004.(3) Jablonowski, N. D., Koeppchen, S., Hofmann, D.,Schäffer, A., Burauel, P.: Persistence of 14C-labeled atrazine and its residues in a fieldlysimeter soil after 22 years. In Press:Env. Poll., DOI: 10.1016/j.envpol.2009.02.004,2009.(4) Jablonowski, N. D., Koeppchen, S., Hofmann, D.,Schäffer, A., Burauel, P.: Spatial distribution andcharacterization of long-term aged14C-labeled atrazine residues in soil.J. Agric. Food Chem.2008,56, 9548-9554.(5) Jablonowski, N. D., Modler, J., Schäffer, A., Burauel, P.: Bioaccessibility of environmentally aged14C-atrazine residues in anagriculturally used soil and its particle-size aggregates.Environ. Sci. Technol.2008,42, 5904-5910.(6) Brun, G. L., MacDonald, R. M., Verge, J., and Aubé, J. Longterm atmospheric deposition of current-use and banned pesticides in AtlanticCanada; 1980-2000. Chemosphere,2008,71, 314–327.(7) Glotfelty, D. E., Seiber, J. N., and Liljedahl,L. A. Pesticides in fog. Nature,1987,325, 602–605.(8) USEPA: National Pesticide Survey: Summary Results of EPA‘s National Survey of Pesticides in Drinking WaterWells.1990.ACKNOWLEDGEMENTSThe SEM analysis by Henrik Daniels, the chemico-physical analysis by ZCH and the valuable help by DianaHofmann/BioSpecare gratefully acknowledged. Thanks to Anita Steffen for laboratory assistance. Sincere thanks are dueto Mr. GünterHenkelmann, LfL Munich, for the lysimeter soil, andto Thomas Pütz for being aware concerning the lysimeters.RESULTSCONCLUSIONS•Thepresented results proof the long-term (>22 years) persistence of atrazine and its metabolites in the environmentand their sorption on gravel, clay-particles and carbonaceous slag-like particles.•Two percent of the gravel-drainage system consisted of carbonaceous slag-like particles of unknown origin – retaining 31% oftotal residual14C-activity in the drainage system•Aside atrazine and its metabolite 2-hydroxy-atrazine (as described previously (3)),all possible atrazine metabolites weredetectedat least in the first extract of the carbonaceous slag-like particles (Figure 1, Figure 2, and Table 1)•The porous structure and the high organic carbon content in the slag-like particles promoted the long-term sorption of atrazineand its metabolites (Figure 3, Table 2)•Porous structure of natural materials likely enhances sorption of organic chemicals in general, due to a high surface area(Figure 3 – Figure 5)•The fact that atrazine and its metabolites were found in the drainage system of a long-term outdoor lysimeter experiment provesthe leaching character of these compounds into deeper soil and/or ground water layers•Carbonaceous materials such as “biochar”, black carbon, etc. can foster the retention of (agro-) chemicals in soils and watersOUTLOOK•Quantification of all detected atrazine metabolites in the ASE-extracts from carbonaceous slag-like particles, gravel and clay is inprogress.26.2 ± 0.11.30 ± 0.012.15 ± 0.013.20 ± 0.021.91 ± 0.016.80 ± 0.030.69 ± 0.021.37 ± 0.0481.55 ± 3.80clay6.16 ± 0.068.65 ± 0.040.18 ± 0.010.44 ± 0.0129.3 ± 0.10.61 ± 0.0110.3 ± 0.00.36 ± 0.00424.44 ± 0.54gravel12.3 ± 0.14.02 ± 0.021.52 ± 0.0110.6 ± 0.111.7 ± 0.17.20 ± 0.040.182 ± 0.02520.0 ± 0.141602.85 ± 9.17slagSiMgKFeCaAlCinorg.Corg.Bq g-1Figure 3:Surface structure of thecarbonaceous slag-like particles. Highporosity likely promotes binding andsorption of atrazine and its residueson a long-time scale over decades.Figure 5:Clay particles attached togravel surface. Atrazine and itsresidues associated with clay particlesfunctioning as a shuttle might promoteleaching of this chemical in groundand surface waters or even drifting bysoil erosion.Figure 4:Surface structure ofpreviously water-extracted gravelpieces. The microscopic poroussurface likely facilitates theentrapment and binding of atrazineand its residues strongly.Table 2:Chemico-physical analysis of the solid samples 1) carbonaceous slag-like material, 2) gravel, and 3) clay particles,which were separated by aqueous shaking extractionof the gravel pieces. Values are in weight %.n= 3Figure 1:Extractionefficiency of aged14C-atrazineresidues fromcarbonaceous slaglike particles, graveland clay, using ASEand methanol-watersolution.Figure 2:Detection of atrazine and all of itsmetabolites was possible in the first extract ofthe slag-like material.INTRODUCTION•Atrazine: s-triazine herbicide, one of the largestselling pesticides worldwide•Severely restricted in the EU, but still widely used in North America, in Africa, in Asia and the Pacific region (1)•Applied on 70% of all corn acreage in the US, corresponding to approx. 26,000 metric tons for the USprogram states only (2)Unexpectedly high persistence of this chemical in the environment (3-5) gives reason to alert, since atrazine has been detectedin ground-, surface and rainwater frequently, and also in fog, ambient air, arctic ice and seawater (e.g.6-8)•Strong sorption and persistence of atrazine and its metabolites on carbonaceous particles is highlighted, providing novel findingson the overall long-term persistence of this chemical and its residues/metabolites on natural soil components.MATERIAL AND METHODS•Used material: gravel-mixture of drainage system (55-60 cm depth) of a long-term lysimeter study (3-5), exposed to threesuccessive annual14C-labeled atrazine applications (1983-1985; 133 mgatrazine in total, corresponding to 56 MBq)•Sample partitioning: 1) gravel; 2) slag-like particles; and 3) clay particles•Microscopic surface analysis of the different particles were conducted using a JEON JSM-840 scanningelectron microscope•Sample preparation: samples were freeze dried, crushed and homogenized in a planetary mill (Retsch PM400)•The chemico-physical analysis: ICP-OES (TJA-IRIS-Intrepid, Thermo; for C-analysis: Leco RC412; for N:Leco TCH 600)•14C-determination: solid samples were oxidized via Biological Oxidizer (OX500 R.J. Harvey Instrument Corp.)•Solid sample extraction: ASE device (ASE 200, Dionex) and methanol-water solution (3)•14C-activity detection: liquid scintillation counter(LSC, 2500 Tri-Carb, Packard)•Detection and quantification of atrazine and its metabolites: LC-MS/MS (Thermo TSQ-Quantum 2002)Table 1:Atrazine and itsmetabolitesdetected insample extracts:5)desisopropyl: slag 1/5-3/5 and gravel 1/5;6)desethyl: slag 1/5 and gravel 1/5;7)2-hydroxy: slag 1/5-5/5, gravel 1/5 and 2/5,clay 1/5-5/5;8)atrazine: slag 1/5, gravel 1/5, clay 1/5.1)desethyl-desisopropyl-2-hydroxy:slag 1/5-5/5, clay 1/5-3/5;2)desethyl-desisopropyl: slag 1/5 and 5/5;3)desisopropyl-2-hydroxy: slag 1/5-5/5;4)desethyl-2-hydroxy: slag 1/5-5/5;