PlasticsFatE Deliverable Report D2.1 Overview of human exposure sources and levels of MP/NP

Various studies show that micro-and nanoplastics (MNPs) virtually occur in almost every environmental compartment, leading to a high likelihood of human exposure to MNPs. Here, different exposure scenarios can occur. The most notable exposure routes of MNPs into the human body are via the airways and gastrointestinal tract (GIT) through inhalation or ingestion, but potentially also via the skin due to the use of personal care products (PCPs) containing small NPs. Once MNPs have entered the human body, it is possible that they are translocated from the exposed tissue to other body compartments. In this deliverable we have summarized recent findings of human MNPs exposure, described the potential translocation pathways of MNPs into the human body and tissues and discussed the current knowledge on the fate of MNPs within the human body. Regarding relevant exposure scenarios, we reviewed the current knowledge on the occurrence of MNPs in food, beverages, personal care products and the air (focusing on indoor air and workplaces). To avoid redundancy to already existing review literature we reviewed the most recent literature starting from 2015. As a result of this literature review, we have decided to focus our review article on the potential translocation pathways and about the current knowledge on the fate of MNP within the human body. Thus, we provide a broad overview of human exposure to MNPs and the potential translocation pathways as a basis for focused research into the putative effects of MNPs on humans. The deliverable was published in a special issue termed “Micro-and Nanoplastics: Environmental and Health Implications” in the peer-review journal NanoImpact in January 2023 (https://doi.org/10.1016/j.impact.2022.100441). Furthermore, we included additional information in the final deliverable 2.1 regarding further exposure scenarios, like hand-to-mouth exposure in children, discussing the relative contribution of the known exposure pathways and the role of additives and contaminants for the potential toxicity of MNPs