Dynamics of glyphosate and aminomethylphosphonic acid in a forest soil in Galicia, north-west Spain.
Residues of the herbicide glyphosate (N-phosphonomethylglicine) and its main metabolite, aminomethylphosphonic acid (AMPA), were determined in a forest soil in north-west Spain, previously treated with 5 and 8 l ha(-1) of glyphosate. Both products were monitored in the solid and liquid soil phases for an 8-week period after the treatment. Soil samples were extracted by KH2PO4. Concentrated extracts and liquid phase samples were derivatized with 9-fluorenylmethyl chloroformate (FMOC) before determination by HPLC using an anion exchange column and spectrofluorometric detection. The treated soil peaked at 6.9 microg g(-1) of glyphosate, whereas soil water samples peaked at 0.74 microg ml(-1) of glyphosate. One month after the treatment, both glyphosate and AMPA concentrations in soil and water samples were almost negligible. AMPA peaked at 0.77 microg ml(-1) in soil water samples. Glyphosate and AMPA exhibited high vertical mobility in the treated soil, quickly reaching high concentrations in subsurface horizons where the degradation is slower.
Veiga
F
F
Department of Soil Science, University of Santiago de Compostela, Escuela Politécnica Superior, Lugo, Spain.
Zapata
J M
JM
Fernandez Marcos
M L
ML
Alvarez
E
E
D004784:Environmental Monitoring; D005998:Glycine / Q000031:analogs & derivatives / Q000032:analysis* / Q000378:metabolism; D006540:Herbicides / Q000032:analysis*; D010573:Pesticide Residues / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D013030:Spain; D014197:Trees; D000097797:Glyphosate
D005998:Glycine; D006540:Herbicides; D010573:Pesticide Residues; D012989:Soil Pollutants; D000097797:Glyphosate