The present disclosure provides a microbiological treatment system including a hydration system and microbiological degradation systems. The hydration system may include a gas-liquid mixing chamber, a gas inlet, a gas outlet, a liquid inlet, and a liquid outlet, the latter four being fluidly coupled to the chamber. The gas inlet is configured to introduce an ethylene oxide exhaust gas into the chamber to mix with an aqueous solution to form an ethylene oxide exhaust liquor. The liquid outlet is configured to discharge the ethylene oxide exhaust liquor. Each microbiological degradation system may include a degradation chamber containing degradation bacteria including one of anaerobic bacteria, facultative bacteria, or aerobic bacteria. The degradation chambers of the microbiological degradation systems may be in fluid communication sequentially in a predetermined degradation sequence, with the most upstream in the degradation sequence having a liquid inlet in fluid communication with the liquid outlet.