Metagenome analysis of different agricultural soils, a wastewater treatment plant (wastewater, sewage sludge, treated wastewater)and private households (washing machines, dishwashers, shower drains) of the same geographical region was performed.

The use of antibiotics in the clinic, humans and animals results in a release of access antibiotic residues into the environment through wastewaters and insufficient removal in wastewater treatment plants (WWTPs). This can lead to the development of antibiotic resistance through increasing bacteria enriched in antibiotic resistance genes (ARGs). However, the knowledge on the potential transfer of ARGs and their host bacteria between different environments remains largely unexplored. We sampled agricultural soils, a WWTP, dishwashers, washing machines and shower drains in the same geographical region and performed metagenomic analyses to evaluate differences and potential overlaps in bacterial communities and the resistome of different environments. Wastewater samples revealed significantly higher richness of ARGs (n=40) and mobile genetic elements (n=52) than soil and household samples. Bacterial communities differed between the environments with pronounced differences between sub-environments of WWTP and household samples. Moreover, antibiotic resistance factors clustered distinctly as well, revealing no correlation between the different environments. Overall, only few overlaps of ARGs between the environments were observed, leading to the conclusion that antibiotic resistances predominantly develop in individual environments as caused by environmental filtering for ARGs, while a transfer between the different environments is less likely.