Colonisation potential of microplastic particles containing organic pollutants by a river-isolated environmental Acinetobacter baumannii

Microplastics in aquatic environments raise concern about their role as potential carriers of pathogens and organic pollutants. This study investigates the survival of the extensively drug-resistant Acinetobacter baumannii in the presence of selected priority substances including benzene derivatives (trichlorobenzene, pentachlorobenzene, and hexachlorobenzene), trifluralin, and primary polyethylene microplastics. The results indicate that the amount of adsorbed priority substances on microplastics from a mixture solution is slightly lower than the adsorption from individual solutions. Furthermore, GC/MS analysis shows that other chemicals used in plastic manufacturing can be released from microplastics into the environment over time and should be taken into account when assessing the environmental impact of microplastics. The proliferation of the environmental Sava 4 A. baumannii strain was not affected by the presence of benzene derivatives and microplastic particles at concentrations of up to 10 g/L in the water medium, and microscopy confirmed that it can colonise and form a biofilm on microplastic particles with adsorbed benzene derivatives, which demonstrates that microplastics have the potential to spread pollutants and potentially harmful bacteria over long distances and introduce them into various aquatic environments.