Tiny particles released as vehicle tires wear down may do more than pollute urban air, water, and soil. A new perspective article suggests that tire microplastics could create environmental hotspots that help antibiotic resistance genes persist, move between bacteria, and spread through cities, according to a Jul. 29 article.
The article, published in Biocontaminant, examines growing evidence linking tire microplastics with antimicrobial resistance. Tire particles are continuously generated by friction between tires and road surfaces. They can then enter the air, wash into stormwater systems, accumulate in rivers and sediments, or settle in urban soils.
"Tire microplastics should not be viewed simply as passive particles that carry pollutants from one place to another," said corresponding author Yuyi Yang of Wuhan Institute of Technology. "Their surfaces, chemical additives, and aging processes may work together to create conditions that favor the persistence and transfer of antibiotic resistance genes."
The researchers identify three main pathways through which tire microplastics may amplify antibiotic resistance risks: development of dense microbial biofilms on the particles (the 'tire plastisphere'), release of complex chemical mixtures including metals and organic compounds that can put bacteria under selective pressure for resistance traits, and increased chemical reactivity due to weathering processes like sunlight exposure, which may enhance gene transfer but also potentially damage genetic material.
The authors emphasize that current evidence remains limited; their review identified only seven studies directly examining tire particles or tire-derived chemicals in relation to antibiotic resistance genes or gene transfer. To better understand these mechanisms, they propose adapting a toxicity identification evaluation framework to isolate different fractions of tire leachates for study.
The findings highlight the need for measures such as stormwater filtration systems and coordinated monitoring efforts connecting environmental management with public health initiatives focused on antimicrobial resistance control.
