Humans are exposed to micro- and nanoplastics (MNPs) in air, food, and drinking water. It is important to understand if these exposures are linked to health risks. But to carry out risk assessments of MNPs, an improved understanding of human exposure levels, as well as the types of impacts MNPs have on human health is required. In this working group, we collect data on different aspects of MNPs which are relevant for assessing the risk to human health, for example: What are the concentrations of MNPs in air, water, and food? What are the physical and chemical properties of MNPs? What amount enters the body, what is the dose at specific organs, and what are typical levels in European populations? We are working together across the projects to advance methods for exposure assessment. We will share best practices for conducting studies; focus on harmonization and generating interoperable data; exchange exposure modelling frameworks; and work to create a common exposure database of MNPs. This will allow for researchers across the projects to efficiently learn from each other and enrich the usefulness of the results for human health risk assessment.