title: A case study of molinate application in a Portuguese rice field: herbicide dissipation and proposal of a clean-up methodology.
abstract: This study was designed to monitor molinate losses in surface and underground waters during Ordram application in a rice field situated in central Portugal. Water samples were collected from different sites, before, during and about one month and a half after Ordram application. Molinate quantification was based on a solid-phase microextraction (SPME) method followed by gas chromatography with flame photometric detector (GC-FPD) analysis, and led to the conclusion that the herbicide was dissipated in the environment, reaching levels as high as 3.9 microgl(-1) in underground water and 15.8 microgl(-1) in the river receiving tail waters. The feasibility of the application of treatment methodologies based on adsorption or biodegradation as processes to remove molinate from real-world waters was assessed. These methods seem suitable to reduce molinate concentrations to values in the range of the legally recommended limits (<0.5 microgl(-1)).
authors.affiliation: Escola Superior de Biotecnologia, R. Dr. António Bernardino de Almeida, 4200-072 Porto, Portugal.
authors.forename: Marisa
authors.initials: M
authors.lastname: Castro
authors.forename: António C
authors.initials: AC
authors.lastname: Silva-Ferreira
authors.forename: Célia M
authors.initials: CM
authors.lastname: Manaia
authors.forename: Olga C
authors.initials: OC
authors.lastname: Nunes
mesh_terms: D001381:Azepines / Q000737:chemistry*; D001673:Biodegradation, Environmental; D002849:Chromatography, Gas; D004784:Environmental Monitoring / Q000706:statistics & numerical data*; D005618:Fresh Water; D006540:Herbicides / Q000737:chemistry*; D011174:Portugal; D012989:Soil Pollutants / Q000032:analysis*; D013859:Thiocarbamates / Q000737:chemistry*; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D001381:Azepines; D006540:Herbicides; D012989:Soil Pollutants; D013859:Thiocarbamates; D014874:Water Pollutants, Chemical; C009821:molinate