ULTRAFILTRATION - A TECHNIQUE FOR DETERMINING THE MOLECULAR-MASS DISTRIBUTION OF GROUP PARAMETERS OF ORGANIC POLLUTANTS IN NATURAL-WATERS

The heterogeneity of dissolved organic matter of natural waters and it s different interactions cause particular analytical problems. As a re sult, a less specific parameter such as dissolved organic carbon (DOG) is often used to describe the sources and fate of organics in aquatic systems. The ion-paired organic-bounded sulfur (IOS) is a new paramet er, and presently includes an important group of sulfur-containing com ponents such as organic sulfonic acids. Natural waters have been chara cterised using ultrafiltration in combination with the determination o f DOC and IOS concentrations. The determination of group parameters fo r different mass fractions (>10 000, 10 000-1000, <1000 g/mol) is a se nsitive approach to obtaining further insight into the fate of dissolv ed organics in aquatic systems.