02067naa a2200241 a 450000100080000000500110000800800410001902200140006002400360007410000200011024501720013026000090030252012650031165300190157665300250159565300200162070000260164070000170166670000200168370000140170370000240171777300840174121705932024-12-12       2024    bl uuuu     u00u1 u    #d  a0718-95087 a10.1007/s42729-024-02135-82DOI1 aSOUSA, E. B. de  aSustainable wet method for determination of total organic carbon in soils using potassium permanganate as a substitute for potassium dichromate.h[electronic resource]  c2024  aPurpose: Official methods for determining total organic carbon (TOC) in soils use wet oxidation with K2Cr2O7, which generates hazardous waste and requires large amounts of concentrated H2SO4, while dry combustion methods with elemental analyzers, although more environmentally friendly and accurate, are costly. This work proposes a new method to mitigate the environmental impacts and costs of determining TOC in soils. Methods: It involves the oxidation of TOC by KMnO4 with the spectrophotometric determination of residual KMnO4. The experimental parameters for oxidation were optimized, establishing a reaction time of 30 min, a temperature of 95 ºC, and 0.125 mol L-1 H2SO4. Results: The oxidizability of a series of organic compounds against KMnO4 and K2Cr2O7 was similar. The appropriate soil mass for the KMnO4 method was defined as 500 mg. Satisfactory linear correlations were observed between the TOC levels obtained using both the KMnO4 method (r = 0.975) and the K2Cr2O7 method (r = 0.972) in relation to the reference (dry combustion) across the analysis of 16 soil samples. Conclusions: The KMnO4 method stood out for its simplicity, reliability, lower cost, and greater safety for the environment and the analyst compared to the K2Cr2O7 method  aDry combustion  aTotal Organic Carbon  aYeomans Bremner1 aNETTO-FERREIRA, J. B.1 aBARRA, C. M.1 aALVES, B. J. R.1 aLã, O. R1 aROCHA JUNIOR, J. G.  tJournal of Soil Science and Plant Nutrition, Publishd online 20 november, 2024.