[Degradation of the herbicide dicamba under strictly anaerobic conditions]

Degradation of the herbicide dicamba was assayed under methane-producing condition using a coastal wetland soil as an inoculum. Benzene ring 14C labeled dicamba was employed and degradative process proceeds through demethoxylation yielding 3,6-dichlorosalicylic acid as the predominant intermediate. The data showed that the degradation rate of dicamba by the enrichment culture achieved 64%, 91% and 95% after 7, 16 and 27 days of incubation, respectively; only small quantities of CO2(0.74%) and CH4(0.11%) were recovered with insignificant radioactivity. The benzene ring of dicamba was not cleavaged to a significant extent. Future cleaning up of dicamba contaminated environment may require an effective bioremediation techniques.