Results of the study provided useful clues on the understanding of
the impact and fate of SMC under anaerobic conditions. For the selected
experimental conditions, the SMX wastewater concentration threshold
for anaerobic bioreactor inhibition was 40 mg/L. Until achieving this toxic dose, the inhibition became limited to substrate binding and
partial impairment of biogas/methane generation; this led to a total
collapse of microbial activity and metabolic functions at doses higher
than the SMX threshold, with reversible impact on acetoclastic methanogenic
activity.