The Potential for Uncoupling and Subsequent Augmentation or Disruption of Methanogenesis by Nonylphenol and Triclosan

摘要

Anaerobic digestion is a critical biosolids stabilization process for wastewater treatment. Whiledigesters are often robust, they can also be susceptible to upsets and foaming. Classical problemsfor digesters include variations in temperature or organic loading rates, but more recentlydigesters have had to deal with an influx of contaminants that accumulate in solids. Little workhas been performed to determine how these contaminants impact the anaerobic digestionprocess. This work focuses on two chemicals found at high levels in digesters: triclosan andnonylphenol. These two chemicals are of greater concern because they could act as uncouplers,i.e., chemicals that cause microbes to respire more without additional growth. In the case ofmethanogenesis, uncoupling could lead to an increase in methane production, but also to thedeath of important microbes. Triclosan elicited signs of uncoupling at 10 μM while nonylphenolwas toxic to pure culture methanogens at 10 μM.