Dynamics of the toxic cyanobacterial microcystin-leucine-arginine peptide in agricultural soil
Résumé
Microcystin-leucine-arginine (MC-LR) is a cyclic heptapeptide hepatotoxin produced by cyanobacteria such as Microcystis aeruginosa. Being highly toxic, this compound is a threat to water quality, agriculture, and human and animal health. In particular, MC-LR has been frequently detected at high concentrations in surface waters. So far, the fate of MC-LR in soils is unknown. Here, we studied degradation and soil–plant transfer of 14C-radiolabelled MC-LR in an artificial system of agricultural soil and tomato seedlings. 14C-MC-LR was dissolved in water and applied by soil irrigation, one or two times with an interval of 28 days. Results show that the 14CO2 from the degradation of 14C-MC-LR amounted to 11 % of total 14C initial input; 74–80 % of 14C-MC-LR occurred in extractible fractions analysed by HPLC. Less than 14 % of 14C-MC-LR was adsorbed on soil particles. Overall, our findings evidence for the first time a high risk of toxin leaching from the soil toward groundwater.
Auteurs, date et publication :
Auteurs Sylvain Corbel , Noureddine Bouaıcha , Christian Mougin
Publication : Environmental Chemistry Letters
Date : 2025
Pages : 7