Effects of Redox Conditions and Substrate Concentration on N-Nitrosodimethylamine (NDMA) Biodegradation

N-Nitrosodimethylamine (NDMA) – known carcinogen has become an emerging issue for reclaimed water which may be used for aquifer recharge or irrigation due to its presence in chlorinated water in nanogram/L. This research investigated the fate of NDMA in two soil column systems used to simulate sub-surface transport. Negligible NDMA removal was observed at 0% reclaimed water and increasing the primary substrate in the influent resulted in NDMA removal suggesting that biodegradation of NDMA might be a cometabolic process. It was observed that NDMA removal was similar under both aerobic and anoxic condition. The majority of NDMA and substrate removal occurred in the first of three columns in series under both aerobic and anoxic conditions. Since the majority of dissolved organic carbon was also removed in the first column, NDMA biodegradation was consistent with co-metabolic activity. Batch tests verified the biodegradation removal potential of NDMA.