TITLE:
Particular Photodegradation Processes of Organic Pollutants in Surface Waters
AUTHORS:
Franklin Ramón Vargas, Yanmey de los Angeles Rojas
KEYWORDS:
Organic Pollutants, Surface Waters, Photosensitizer, Photodynamic, Photo-Oxidation
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.14 No.9,
September
24,
2026
ABSTRACT: This article describes the processes that affect the chemical composition of surface waters, including annual, seasonal, and long-term variations. It provides an overview of the effect of sunlight penetration into the water column of natural water bodies. Photochemical processes are strongly affected by sunlight irradiation, the penetration of which into the water column depends on several factors, such as the magnitude and color of suspended solids and colloids, the presence of phytoplankton, particulate and dissolved organic matter, among others. Different photochemical processes are shown and discussed throughout this work. The photo transformation of pollutants in waters from natural environments, such as pesticides, detergents, and pharmaceuticals (drugs as emerging pollutants), is summarized. These techniques can be used in laboratory experiments to simulate the abiotic transformation of these pollutants in the euphotic zone (the zone with the greatest light reception), which sometimes leads to potentially harmful transformation intermediates. Similarly, the role played by reactive oxygen species (superoxide anion, singlet oxygen, hydroxyl radicals) in surface waters is described. The latter, produced in aqueous solution by photo-excited organic matter, has a micro-heterogeneous distribution in the solid phase and in the hydrophobic nuclei of humic substances, which can have important implications for the degradation of hydrophilic and hydrophobic pollutants.