Sources, Occurrence, and Environmental Risk Assessment of Antibiotics and Antimicrobial-Resistant Bacteria in Aquatic Environments of Poland

Abstract

Antimicrobial compounds are widely used in human and veterinary medicine to protect human and animal health, to prevent economic losses, and to help to ensure a safe food supply. After administration, the antibiotics and their transformant products (TPs) may pass through the sewage system and end up in the environment, mainly in the water bodies. Apart from antibiotics and their TPs, antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs), which have been identified as emerging pollutants of concern, enter ecosystems with treated wastewater and livestock manure. In the environment altered by human activity, the occurrence of bacteria resistant to almost all known antibiotics has been confirmed. Despite being universally considered relatively important, land runoff, drainage and seepage are not the sites with the most striking occurrence of the transfer of resistance genes among different species of bacteria. The most significant hot-spots are wastewater treatment plants (WWTPs). Together with treated wastewater which is released from WWTPs, antibiotics, their TPs, ARB, and ARGs can penetrate the surface water, rural groundwater supplies, drinking water, soil, and plants growing in soil irrigated with contaminated water. It creates a direct risk to human and animal health because drugs, ARGs, and ARB transported to the environment can be transferred back to people and animals. The authors of this article aim to familiarize readers with the phenomenon of antibiotic resistance in Poland: its occurrence, ranges of antibiotic concentration, and the number of ARB and ARGs occurring in Polish surface waters as well as main sources of these contaminants.