Sources, behaviour and health risks of antimicrobial resistance genes in wastewaters: A hotspot reservoir

•Multiple hotspot sources emit antibiotic resistance genes (ARGs) into wastewaters.•Wastewater treatment processes contribute to the persistence and fate of ARGs.•Vectors, contaminated water and food transfer ARGs from wastewater to humans.•Complex human-environmental interactions control the behaviour and fate of ARGs.•Risks assessments should include interaction of ARGs and environmental stressors.