SOLID-PHASE MICROEXTRACTION (SPME) OF THE HERBICIDE ATRAZINE IN AQUEOUS SOIL SUSPENSIONS

A new method for the direct SPME of atrazine in soil slurries (20 g so il/L) followed by cleaning of the fibre has been developed enabling se quential extraction of at least 15 soil samples with good reproducibil ity. No relevant interferences were observed using an EC detector at t he lowest atrazine concentration examined (<10(-7) mol/L). Good resolu tion was obtained and the method was linear over the range of concentr ations studied (<10(-7)-10(-4) mol/L). Data from the SPME-GC method co rrelate very well with the data from microfiltration-HPLC measurements , suggesting that by both methods the freely dissolved atrazine alone is being measured. Thus a new simple, clean, solventless extraction te chnique, easily compatible with capillary GC, has been added to the ar senal of methods available for the analysis of less volatile compounds from soils and water bodies with a high content of particulate and hu mic materials.