Characterization of dissolved organic matter (DOM) in landfill leachates using fluorescence excitation-emission matrix

The analysis of dissolved organic matter (DOM) in landfill leachates consti tutes a major challenge since they are made of a large number of unknown mo lecules. Due to this complex chemical composition, the questions of their g eographic or climatic specificity as well as their evolution in time due to biodegradation processes will not be explained until a proper method to ch aracterize the leachates is designed. In a previous report [1] we elaborate d a new method for the fractionation of organic matter in landfill leachate s. Here we present an improved method of DOM spectral characterization base d on fluorescence excitation-emission matrices (EEM) combined with band cur ve-fitting of the excitation and emission spectra. The fluorescence spectro scopy has proved to be a potent tool in analytical chemistry in various con texts. Particularly, excitation-emission matrices have been used to describ e the spectroscopic properties of the organic matter dissolved in fresh or marine waters. High resolution is attained by band curve-fitting which allo ws resolution, of discrete components that overlap in the experimental emis sion spectra. Hence, most of the fluorescence excitation/emission maxima re lated to a sample are determined, even though they do not generate a local maximum in the EEM. The present paper reports an application of this method to the characterization of ultrafiltrated leachates fractions collected in a domestic landfill in Brittany (France).