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The organic material from cyanobacteria is a significant precursor to the generation of disinfection byproducts. This study's aim was to evaluate the formation of assimilable organic carbon (AOC) in water contaminated with cyanobacteria. Furthermore, the formation of AOC was related to the generation of trihalomethanes (THMs) and dissolved organic carbon (DOC). The advanced oxidation process was caISOrried out by exposing Microcystis aeruginosa cells (250,000 cells mL−1) to different peroxide dosages (10 to 100 mg L−1) under ultraviolet radiation. Pseudomonas fluorescens (P-17), Spirillum sp. (NOX), and flow cytometry were used to determine the AOC concentration. The formation of AOC and THMs during the UV/H2O2 process was not directly related. The AOC concentration increased with low H2O2 doses and decreased at higher concentrations, while the levels of THMs decreased regardless of the AOC formed. After oxidation, the DOC concentration decreased, along with the concentration of THMs. Additionally, it was observed that the behavior of DOC and AOC is inversely proportional. These results suggest that the oxidation process has a complex effect on organic matter, influencing byproduct formation and AOC availability. Moreover, these findings highlight the importance of carefully monitoring and controlling the oxidation processes to better understand their impact on water treatment and byproduct formation. [ABSTRACT FROM AUTHOR]

Given the issue of lipids in effluent treatment systems and their negative impact on the environment, this study aimed to examine lipid degradation by homogenous catalytic ozonation with the aid of iron and manganese ions. This technology presents the possibility of completely mineralizing pollutants using hydroxyl radicals. Milk is chosen as the lipid source because of the high concentration of triglycerides in its matrix, this kind of lipid being the one found most frequently in food and, consequently, in effluent treatment systems. The milk pH value is controlled, and acidic, neutral, and basic conditions are evaluated. The rates of pseudo‐first‐order reactions and the effective value are estimated. It is shown that under acidic conditions low catalyst dosages are enough to cause the complete degradation of lipids. Under neutral conditions, a similar behavior is observed. Under basic conditions, higher catalyst dosages give higher reaction rates. The order of effectiveness of the catalysts under acidic and basic conditions is Fe2+ > Mn2+, with Mn2+ > Fe2+ under neutral conditions. Homogeneous catalytic ozonation is therefore efficient at lipid degradation. This technique is viable economically, since the lipid removal occurred at low ozone levels. In addition, the ions used as catalysts are naturally abundant. [ABSTRACT FROM AUTHOR]