Effect of light on humic substances: Production of reactive species

Under photochemical excitation, humic substances produce reactive species which can degrade a great variety of :organic compounds. : Solvated electrons, hydroxyl radicals, singlet oxygen and reactive triplet states were characterized using probe molecules: and scavenging techniques. The quantum yield of formation of these species depends on the irradiation wave-length,on oxygen concentration and on the origin of the humic substances, Through their photoinductive properties, humic substances can be used to degrade pollutants.