Análise de contaminantes ambientais em ecossistemas aquáticos, empregando extração em fase sólida e técnica cromatográfica e espectrométrica

Abstract

Many organic and inorganic contaminants are present in the interest in optimization and developing tecniques of sample preparation hás increased to mk possible pré-concentration of these analytes from this médium to be adquqte for the detection system to be used. In this work solid phase extration (SPE) was used to extract and pré-concentrate pesticide and heavy metals in water. The pesticide studied was organophosphorus (OP) temephos. For the identification and quantification of the temephos high perfomance liquid chromatography (HPLC) wiht an analytical column C18 Varian, 250 mm x 4,6 mm d.i, particle size 5μm was used. The mobile-phase used was ACN:H2O 85:15 v/v and detection used diode array spectrophotomoter. The Best volumes of samples used in the extration was 100 mL with cartridges of C18 (pré-concentration factor of 100 times). The recovery studies were performed at two levels of fortification (10 e 20μg.L-1

). The average recoveries were between 100 to 101%. The coefficients variation. Was foud of less 4,5%. The limits of detection and quantification of the method were 4,8 x 10-3

and 1,46 x 10-3 mg.L-1

respectively. After the development of the method was applied in water samples for human consumption. For determination of the concentrations of studied metals inductively coupled plasma mass spectrometry (ICP-MS), Varian (model 700ES) was used. The recovery studies were performed with fortification of 0,5 and 2,0 mg.L-1

for cadmium and lead respectively. The averege recoveries were 86,1% for cadmium and 75,5% for lead. After optimization of the method was applied in superfial water samples.