Compreender o papel de microplásticos na disseminação e transferência trófica de agentes patogénicos resistentes a antibióticos.

The association of ARB with MPs may amplify the negative impacts of MP pollution on One Health. Yet, research on MPs-ARB combined effects is still at early stages. We need to address the following questions: 1) What factors promote MPs colonization by ARB? 2) Do biofilm conditions enhance ARB survival in the environment? 3) Are biofilm-coated MPs more attractive for animal consumption? 4) If biofilm-coated MPs are ingested/internalized, could ARB transfer to the host microbiome? 5) Can ARB on MPs move across the food chain? and 6) Do MPs-ARB synergistically affect the organisms? PLASTICBUG will advance knowledge by addressing these questions in an innovative, integrative and transdisciplinary manner. The analysis spans the entire process and its effects, from ARB attachment to MPs to their co-transfer to animals and plants and to subsequent trophic levels. Our main goal is to understand MPs role as vectors of ARB and priority pathogens in freshwater ecosystems and the food chain. Specifically, we aim: 1 - To identify factors that stimulate MPs and ARB association. This will be achieved by exposing MPs in distinct locations along a model river, quantifying ARB and ARGs in the plastisphere (6 polymers) and correlating these data with water quality parameters and pollutants concentrations. Results will be validated in microcosms. Prioritization of polymers and AMR-selective agents as the most likely deterministic factors, and the use of representative particles in environmentally realistic concentrations, will inform strategies to combat MPs-ARB association. 2 - To assess MPs impact on ARB survival in the environment. We will conduct microcosm-based experiments using river water spiked with priority pathogens (4 strains representing the 4 groups listed as priorities by WHO). Effects of MPs on the survival of these pathogens were never investigated. This data is vital for assessing MPs health impact, as the prolonged bacterial survival in the environment increases exposure risks for animals and humans. 3 - To quantify MPs-ARB uptake/internalization of MPs-ARB by plants and animals. We will expose edible plants (i.e., lettuce and tomato) and a key aquatic insect species to environmentally relevant concentrations of MPs coated with priority pathogens. Few studies have tested the uptake/internalization of MPs-ARB, and in a limited number of species. 4 - To demonstrate the transfer of priority pathogens to the organisms’ microbiome. By testing priority pathogens transfer, PLASTICBUG will identify additional health risks of MPs, also addressing the concern of MPs contamination in food. 5 – To demonstrate MPs-ARB transfer to higher trophic levels. We will feed animals contaminated with MPs-ARB to consumers of other species. This will confirm MPs role as vectors of ARB along the food chain, potentially reaching humans, and shedding light on their true global health effects. 6 - To evaluate MPs-ARB cumulative adverse effects on animals and plants. We will analyze plant growth and physiology; and toxic effects on organisms at sub-organismal, organismal and population levels. This will allow a comprehensive assessment of MPs-ARB toxicity at environmentally relevant concentrations and for different types of plastics. PLASTICBUG results will help improving national and regional action plans to protect ecosystems and combat AMR, provide risk assessment methods and inform policymakers. Awareness, education and dialogue with stakeholders are priorities.