[en] Complete text of publication follows. In the present study, we illustrate an extension of the well-established reaction of molybdate-catalysed iodide H₂O₂ assay towards a kinetic analysis of organic hydroperoxides, ROOH. When the rate of the reaction of a given ROOH ≥ 10 times slower than that of H₂O₂, the yields of H₂O₂ and ROOH can be determined by conventional UV/Vis spectrometry (time-drive mode). As examples, we will discuss the formation and characterisation of CH₃OOH and CH₃CH(OH)CH₂OOH formed upon γ-radiolysis of oxygenated aqueous solutions of dimethylsulfoxide and 2-propanol, respectively. When the reactivity of H₂O₂ and ROOH is similar, H₂O₂ can be destroyed with catalase. However, the stability of ROOH toward catalase must be checked, since formic peracid, for example, is also rapidly destroyed by catalase. Highly reactive ROOH such as formic peracid or those derived from thymine ozonation can be distinguished from H₂O₂, because they react also readily with iodide without molybdate catalysis while H₂O₂ does not. They are also capable of oxidizing sulfides and disulfides by O-transfer. The reaction with formic peracid can be readily followed by conductance measurements, because formate ions and protons are liberated in this reaction (pK_a(formic peracid) = 7.1, pK_a(formic acid) = 3.8). Ozonolysis of olefins produces one mol of ROOH per one mol O₃ consumed and is a most useful approach for generating ROOH. On the basis of recent data, we will discuss the formation and fate of some hydroperoxides which have been of interest in the area of radiation chemistry for some time, including that of polymers