Patterns of the Disperse-phase Distribution of Organic Ecotoxicants in the Water of the World River Systems

The results of the dispersed-phase distribution of major classes of organic ecotoxicants such as organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in the water of various river systems have been discussed in the current research. The main parameters of water quality in these river systems differ significantly. Despite this, the following constancy has been established for all studied river systems: the higher the hydrophobicity coefficient log (Ko/w) of the organic ecotoxicant, the smaller its water-soluble fraction. Relevant dependences have been established and their statistical processing has been carried out. The correlations determined are significant and reliable for most aquatic systems, with R ranging from 0.67 to 0.98 (P > 95%). It follows that the hydrophobicity coefficient of a compound is an essential parameter by which its disperse-phase distribution can be estimated. The results were almost identical for the Dnieper and Elbe rivers due to the similar physicochemical characteristics of these water systems.