02286naa a2200385 a 450000100080000000500110000800800410001902400350006010000190009524501530011426000090026752010830027665000220135965000290138165000260141065000220143665000260145865000090148465000190149365000220151265000180153465000140155265000250156665000220159165000090161365300330162265300180165565300210167370000280169470000210172270000170174370000160176070000210177677301030179720033582014-12-19       2014    bl uuuu     u00u1 u    #d7 a10.1007/s00128-014-1330-62DOI1 aASSALIN, M. R.  aA method for determination of imazapic and imazethapyr residues in soil using an ultrasonic assisted extraction and LC-MS/MS.h[electronic resource]  c2014  aAbstract At least 52 % of the planted rice area in Rio Grande do Sul, a major rice producing state in Brazil, employs Clearfield Ò production system, corresponding to 580,000 ha of cultivated area. To grow rice with Clear- field Ò technology, producers combine imazethapyr and imazapic herbicides. However, these herbicides leave residual activity in soil; consequently, the repeated appli- cation of imazethapyr and imazapic on Brazilian Clear- field Ò rice fields has increased these herbicides persistence in treated soils. In this study, a method has been developed for removal and quantification of imazethapyr and imaza- pic residues in soil through ultrasonic assisted extraction using methanol?phosphoric acid aqueous solution (pH 2.0). The detected response was linear for both herbicides within the range of 0.25?5 ng mL -1 with correlations coefficients [0.99. The quantification limit was limit of quantification 0.2 lg Kg -1 for both pesticides. The good recovery rate from all pesticides, which ranges between 70 % and 120 %, demonstrates the method?s validity.  aChemical analysis  aImidazolinone herbicides  aLiquid chromatography  aMass spectrometry  aMultiresidue analysis  asoil  aSoil pollution  aAnálise química  aCromatografia  aHerbicida  aPoluição ambiental  aResíduo químico  aSolo  aClearfield production system  aImidazolinone  aResidue analysis1 aQUEIROZ, S. C. do N. de1 aFERRACINI, V. L.1 aOLIVEIRA, T.1 aVILHENA, E.1 aMATTOS, M. L. T.  tBulletin of Environmental Contamination and Toxicology, Californiagv. 93, n. 3, p. 362-364, 2014.