Characterization of organic matter in natural waters by EEM fluorescence properties

Abstract

Natural organic matter (NOM) as the main component of natural colloidal matter is a major concern in drinking water treatment due to well-documented disadvantages. The understanding of NOM properties is a crucial factor to determine the dissolved organic matter treatability. The main purpose of this study is to provide information for realization of physicochemical and compositional properties of NOM in relation to the impact factors related to the surface water quality. To achieve this goal, water samples were collected from major watersources of Istanbul as well as from lakes located in various parts of Turkey. A consistent data-set of basic parameters specifically related to the quantification of organic matter contents, namely dissolved organic carbon and spectroscopic parameters (UV–vis and fluorescence) of selected surface waters were evaluated. Besides UV–vis spectral parameters, fluorescence intensity as represented by the ratio of the emission intensity at λemis450nm to that at λemis500 nm, following excitation at λexc370nm was also successfully employed. Moreover, fluorescence fingerprinting of surface waters by using emission excitation matrix (EEM) features as a tool was explored. These analytical techniques could contribute to the knowledge and understanding of the characterization and composition of NOM in surface waters. Based on the attained results, it could be indicated that EEM contour plots could be successfully utilized as a tool in understanding of the organic matter present in natural waters.