02098nam a2200205 a 450000100080000000500110000800800410001910000200006024501050008026001980018552013730038365000130175665000110176965000100178065300200179070000210181070000240183170000170185570000200187220779012017-10-23       2004    bl uuuu     u00u1 u    #d1 aCERDEIRA, A. L.  aPresence of Atrazine in Water in a Recharge Area of Guarany Aquifer in Brazilh[electronic resource]  aIn: ANNUAL MISSISSIPPI WATER RESOURCES CONFERENCE, 34., 2004, Jackson. Proceedings... Raymond: Mississippi Sate University: Mississippi Water Resources Research Institute, 2004. p. 43-46.c2004  aThe region of Ribeirao Preto City located in Sao Paulo State, southeastern Brazil, is an important sugarcane, soybean and corn producing area. This region is also an important recharge area for groundwater of the Guarany aquifer, a water supply source of the city and region. The cultivation of grain and sugar cane in thes area demands the frequent use of the herbicide atrazine (2-chloro-4- (ethylamino)-6-(isopropylamino)-S-triazine). This research was conducted to characterize the potential contamination of groundwater with atrazine. Surface water samples were collected in the Espraiado stream in a selected watershed on the area, during the years of 1995-1998. Groundwater was also collected in wells located at the edge of the watershed during the years of 1999 to 2002. The water samples were analyzed by HPLC (High Performance Liquid Chromatography) procedure followed by GC-MS form confirmation. To predict the atrazine leaching in the area, the CMLS-94 (Chemical Movement Layered Soil) simulation model was also used. Only four atrazine detections in surface water were found, however, none of them were confirmed with GC-MS. No atrazine was detected in groundwater samples. The results obtained by the CMLS-94 simulations predicted that atrazine, after four years from the application date, would not have reached the depth of the confined aquifer (40m).  aatrazine  aBrazil  awater  aGuarany Aquifer1 aSANTOS, N. A. G.1 aPESSOA, M. C. P. Y.1 aSMITH JR, S.1 aLANCHOTE, V. L.