Persistence and leaching of some residual herbicides in uncropped soils

• Published in: Bulletin of environmental contamination and toxicology 1996-02, Vol.56 (2), p.219-224
• Main Authors: Gomez de Barreda, D. (I.V.I.A. Generalitat Valenciana, Valencia, Spain.), Lorenzo, E, Gamon, M, Walker, A, Ramos, C, Saez, A, Carbonell, E.A, Garcia de la Cuadra, J, Munoz, N, Busto, A. del
• Format: Article
• Language: English
• Subjects: ESPAGNE; ESPANA; HERBICIDAS; HERBICIDE; HERBICIDES; LEACHING; LESSIVAGE DU SOL; LIXIVIACION; LOAM SOILS; RESIDU; RESIDUES; RESIDUOS; SOL SABLOLIMONEUX; SPAIN; SUELO FRANCO
• ISSN: 0007-4861; 1432-0800
• DOI: 10.1007/s001289900033

Atrazine, bromacil, terbuthylazine, terbumetone, terbutryn, diuron, and simazine were applied at approximately five times the commercial dose to uncropped plots of loam soil. Plots were flooded one day after application, and at intervals when the evaporation in an evaporation pan was cumulatively more than 60 mm. Soil samples were collected, extracted and analyzed at intervals ranging from 14 to 166 days. Although residues of all herbicides were found at depths of 20 to 30 cm, the highest concentration was generally in the top 10 cm of soil. using gas chromatography. Results generally agreed with those of another study that showed that bromacil leached fastest, followed by atrazine. Diuron, simazine, terbuthylazine and terbumetone leached at similar rates, that were slower than atrazine, but faster than terbutryn. In one field, a commercial mixture containing terbutryn, terbuthylazine, and terbumetone was applied. Terbuthylazine degraded more slowly than the other two compounds. Terbutryn was the least persistent of the compounds. Within a year, complete degradation of the herbicide was demonstrated, showing that soil buildup of residues is unlikely.