Cyanotoxin degradation evaluation through low frequency ultrasound

Cyanotoxins, such as microcystins (MC) and nodularins (NOD), are highly stable and resistant to conventional physical and chemical degradation, posing a significant risk to human health. In the present work, low frequency ultrasound was used as an advanced oxidation process to degrade cyanotoxins from a Colombian reservoir, evaluating the efficiency of the sonication process, using different powers (10, 30 and 50 W) and exposure times (5, 10, 20 and 30 min) under a frequency of 40 kHz. Ultrasonication proved to be ineffective for MC-LR concentrations up to 2595.42 μg/L, as no significant degradation was observed after 30 minutes of treatment. Additionally, a notable difference was evident in the concentrations of cyanotoxins in the water between sampling campaigns. Thus, risk assessment, implementation of monitoring programs and mitigation efforts in reservoirs deserve greater attention.