Nanoplastic- Fungi interaction – insights from various laboratory scales

Nanoplastic (NP) exposure to the terrestrial water cycle poses an emerging threat to subsurface ecosystems, while the continuous release of NP increases the risk of drinking water contamination.
Fungal communities are a crucial component of terrestrial ecosystems. Traditionally, their presence and functions have been studied in shallow soils as part of the soil microbiome or above ground as decomposers or pathogens. Recent mycobiome screening studies of groundwater wells have revealed the presence of fungal species in deeper aquifers. This confirms the presence of fungi across all compartments of the terrestrial water cycle, highlighting the need to investigate their role in contaminant transport processes.
Fungi have demonstrated the ability to immobilize dissolved organic contaminants, heavy metals, and pharmaceuticals from polluted waters. However, studies examining their effect on NP removal remain limited. Existing research generally lacks the integration of liquid flow dynamics, which is crucial for understanding fungal interactions in natural water systems.
We present a dataset, which shows dynamics of NP-fungi interaction across multiple laboratory scales. Our study compares batch adsorption experiments with transport experiments conducted in inoculated microfluidic chips and transport columns. Carboxylated polystyrene nanoparticles of 100 nm and 250 nm serve as model NPs. Following fungal inoculation in growth media, the experiments are conducted under various ion concentrations of CaCl and flow velocities ranging from 1 m/d and 30 m/d.
Our results indicate scale-dependent modes of NP-fungal interactions. In batch-scale experiments, higher ion concentrations significantly enhance the adsorption efficiency of NPs to fungal hyphae. In contrast, experiments conducted in microfluidic chips and transport columns reveal altered behavior, with notably lower adsorption efficiencies observed.
This suggests that in natural environments, factors such as the spatial distribution of hyphae, ion concentration, flow rates, and consequently reaction times, collectively influence the efficiency of NP removal by fungal communities.