Selection for antimicrobial resistance in the plastisphere.

Area of Science:

• Environmental Science
• Microbiology
• Toxicology

Background:

• Microplastics and antimicrobials are pervasive global contaminants.
• Their combined impact on antimicrobial resistance (AMR) in the 'Plastisphere' (microplastic-associated microbial communities) is poorly understood.
• Existing research often studies these contaminants in isolation.

Purpose of the Study:

• To propose mechanisms by which microplastic-antimicrobial interactions drive AMR selection in the Plastisphere.
• To highlight the implications for ecological functioning and environmental risk assessment.
• To recommend future research directions.

Main Methods:

• Review of existing literature on microplastics, antimicrobials, and AMR.
• Analysis of proposed interaction mechanisms.
• Discussion of ecological and risk assessment implications.

Main Results:

• Microplastic-antimicrobial co-occurrence can increase horizontal gene transfer rates in the Plastisphere.
• Microplastics can concentrate AMR-selective compounds, elevating selection pressure.
• Incorporation of antimicrobials/co-selective agents into plastic matrices may further increase AMR selection pressure.

Conclusions:

• The interaction between microplastics and antimicrobials presents a significant, understudied driver of AMR.
• Understanding these mechanisms is crucial for accurate environmental risk assessment.
• Further research is needed to fully elucidate the complex interplay and its consequences.