PlastiSpread

Antimicrobial resistance (AMR) and marine plastic pollution are major global health and environmental concerns. Despite this, there is limited knowledge concerning the occurrence of pathogens and antibiotic resistant bacteria (ARB) in Norwegian wastewater (WW) effluents from urban areas and in the coastal marine environments into which they are discharged. Furthermore, the potential role of plastics as a vector for the transmission of pathogens, ARB and antibiotic resistant genes (ARG) throughout the marine environment is poorly understood. PlastiSpread will provide important new knowledge about the microbial community in biofilms associated with marine plastics, and how they are influenced by variations in urban WW discharges. Such findings will help evaluate the potential role of marine (micro)plastic litter to act as a reservoir and vector for the development and spread of AMR and pathogenic bacteria in marine environments and more widely into the human food chain. A novel approach, integrating field- and lab-scale plastic model systems will be used to investigate the influence of WW effluent composition and polymer type on the bacterial community composition in plastic-associated biofilms, including occurrence of potential pathogens, ARB and ARGs. The field model system will be situated at selected exposed and non-exposed sites in Trondheim Fjord, where marine bivalve mollusks will also be used as indicators for exploring effects on marine organisms present at the same sites. A highly novel aspect of PlastiSpread will be to determine experimentally the process of horizontal gene transfer of ARGs from WW to susceptible plastic-associated biofilm bacteria. Greece has the highest consumption of antibiotics in Europe (double that of Norway). PlastiSpread investigates how this influences the occurrence of ARB and ARGs in local effluent WW through a set of complementary studies conducted in Greece using the same plastic materials and methods.