Biodegradation potential of fenthion and disulfoton on inoculated biochar through alluvial Danube sediment

Increased pesticide uses over the last few decades raise a serious threat to environment, especially to the groundwater the most important drinking water resource. This work investigates the biodegradation potential of two selected organophosphorus pesticides, OPPs (fenthion and disulfoton) on Danube alluvial sediment in the presence of microbially inoculated biochar (BC). The investigated BC was produced by slow pyrolysis of the Miscanthus giganteus at a temperature of 400°C. Bacillus megaterium BD5 was isolated from the alluvial Danube sediment sample and was successfully immobilized on BC in the form of vegetative cells and endospores. The breakthrough curve of thiourea as a nonsorbing substance was symmetrical, indicating absence of physical nonequilibrium processes in porous media. In general, the results indicate that the R_d coefficient for fenthion (R_d=30) is higher than the R_d for disulfoton (R_d=20), but higher biodegradation was observed for disulfoton (λ=6) than for fenthion (λ=4.5). The highest biodegradation could be a consequence of high adsorption on BC and biosorption. Further enhancement of the biodegradation processes could be achieved by integration with bioelectrochemical remediation system, which will be done in the future experiments.

Acknowledgment. Funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or European Research Executive Agency (REA). Neither the European Union nor the granting authority can be held responsible for them. Grant agreement No. 101059546