The transferable resistome of biosolids—plasmid sequencing reveals carriage of clinically relevant antibiotic resistance genes

This study emphasizes the critical role of wastewater treatment plants (WWTPs) in facilitating the horizontal transfer of ARGs through biosolids. As biosolids are routinely applied to agricultural soils, their load of clinically relevant ARG content and transferability pose risks to animal and human health through plant-associated bacteria or surface water. By identifying conserved ARG-MGE associations across diverse plasmid types and WWTPs, this work highlights the global and persistent nature of resistance dissemination. These findings underscore the urgent need for sustainable management practices to limit the spread of antimicrobial-resistant bacteria (ARB) and associated ARGs in agricultural ecosystems. Ensuring safe biosolid use will contribute to combating antimicrobial resistance gene connectivity from environmental to human- or animal-associated bacteria globally.