Despite a constant increase in plastic worldwide production, the environmental risk linked to microplastics remains little studied today. The PLASTERA project aims to define this risk in a global pollution context in the Loire River and its estuary, while considering environmental, animal and human health. This project will be divided into four phases: i) to characterize the plastic exposome in the Loire River and its estuary, ii) the use of an active biomonitoring approach to assess its effects on various sentinel species, iii) to characterize the effects of these environmental contaminants from bivalves to humans at sub-individual levels and iv) to provide data to help regulation of this emerging contamination while raising citizen awareness of this contamination. This project aims to be in line with the "One Health" concept considering environmental health (determination of contamination and its effects at the level of four habitats: freshwater / marine water / benthic / endobenthic), animal and human health (in situ exposures of sentinel species in these habitats and in vitro exposures of animal and human immune cells). The new IBR-T index (integrative biomarker responses) will be deployed to summarize the effects of this contamination and raise awareness of the general public, communities and other stakeholders.