Antimicrobial Resistance – A Growing Global Groundwater Challenge

Thomas Boving , Cecilia Hernández-Zepeda, Dan Lapworth, Melissa Lenczewski, Bhanu Prakash Vellanki

Antimicrobials are composed of medications such as antibiotics and antivirals which are widely used to ensure human and animal health. However, inappropriate use of antimicrobials is a major driver of antimicrobial resistance. AMR arises from complex interactions between humans, animals, microbial organisms, medicines, wildlife and the environment. Once in the wastewater stream, antibiotics are only partially removed by most wastewater treatment plants and are frequently detected in both effluent water and sludges. Bacteria can develop antibiotic resistance through several mechanisms such as genetic mutations or by acquiring antibiotic resistance genes (ARGs) from other bacteria via horizontal gene transfer. Based on studies worldwide, hundreds of ARGs have been detected in various aquatic systems, posing significant environmental and public health concerns. Once in the environment, ARGs can disseminate within bacterial populations from which some species could re-enter human and animal systems via contaminated water, food, or recreational activities. This environmental reservoir of resistance undermines the effectiveness of antibiotic therapies, complicates the treatment of infectious diseases, and increases the risk of outbreaks caused by multidrug-resistant pathogens. The current strategy of preventing AMR is to protect aquatic environments from pharmaceutical contamination, especially antibiotics. But because of the difficulty and expense of detecting compounds associated with AMR, most countries do not have national, legally enforceable water quality standards. Further developments in affordable screening and treatment solutions will be necessary to tackle this insidious contamination.