Food for thought: The uptake, translocation and trophic transfer of micro- and nanoplastics via agriculture into the human food basket

Micro- and nanoplastics (MNPs) are widely recognized as contaminants of emergent concern. Recent research showed that agricultural soils are a sink for MNPs. It is demonstrated that MNPs not only have adverse effects on crops but that plants can take up these particles. This means that humans, as well as herbivores, can potentially accumulate MNPs via this pathway.

Goal

The objective of this research project is to quantify the uptake and transfer of MNPs in edible plants and edible organisms. This provides key data about the risks of MNPs in our food. Specifically, the following research questions will be answered:

1. What are the kinetics of uptake, translocations, and trophic transfer of MNPs from edible plants (e.g. lettuce, wheat, carrot, or spinach) into edible animals (e.g., escargots or caterpillars)?
2. How do the physico-chemical characteristics (e.g., size, polymer type) of the MNPs impact these processes?

Importantly, the selection of edible organisms represents a proof-of-principle on whether MNPs are trafficking through the food chain. Additionally, it provides key novel insight into accumulation in our food, as they are part of the human food basket around the world and seen as Future Food.

Approach/method

The researchers will expose plants (e.g., lettuce, spinach, carrots, or wheat) to different types of metal-labelled MNPs. Levels of different metals are measured in the roots and shoots, as well as in the exposure media. Subsequently, plant tissues are fed to edible animals (escargot or caterpillar) to determine the uptake and trophic transfer of particles into different tissues. They will also assess the impacts of MNPs on plants, as well as on herbivorous consumers.

Collaboration partners

This project is carried out by dr. ir. T. Bosker and colleagues from Leiden University. They work together with researchers from Utrecht University and RIVM.

(Expected) results

This study will provide key novel data on an understudied exposure pathway: from plants to animals and further on to humans. Our results will provide key data on whether MNPs can traffic through the food chain . It will also provide new insight into the potential of MNPs to accumulate within the human food basket.

Continuation

This research will directly contribute to the overarching framework for health impact assessment of MNPs, which is developed in MOMENTUM 2.0. Importantly, knowledge will be shared within several key European projects on plastic pollution, as well as with regulating bodies within the EU and FAO