Conventional aqueous amine scrubber solutions of MDEA for CO2 capture generally contain a high concentration of MDEA corresponding to 1.5M to 2.5M 24 . These MDEA concentration levels would inhibit the methanogenic activity as suggested in figure , and it would therefore be necessary for the system to operate with lower MDEA concentrations for the absorption unit. The CH4 production rates and biocompatibility presented in this study were based solely on the initial performance of a mixed anaerobic sludge culture. In contrast, a continuously operated bioreactor is expected to favor microbial adaptation to the presence of aqueous amines by metabolic regulations and enrichments in the mixed culture, which would increase their tolerance for the aqueous amine solution. Thus, the microbes would presumably be able to demonstrate higher conversion efficiencies at higher amine concentrations during long-term operation, as has previously been demonstrated for other toxic mediums as i.e. ammonia-rich mediums .