Tyre and road wear particles as carriers of metals and rare earth elements: Evidence of bioaccumulation in Tenebrio molitor

Tyre and road wear particles (TRWPs) are a significant source of micro- and nanoparticles contamination of aquatic environments. However, their occurrence and biological effects in terrestrial ecosystems remain poorly investigated, including their role as carriers of trace elements. This study, therefore, examines the accumulation of trace elements in Tenebrio molitor following exposure to TRWPs. Adults were fed organic wheat flour contaminated with 5 % and 10 % (w/w) TRWP powder, simulating concentration in soils near high-traffic areas. Chemical analyses of TRWPs and treated and control beetles at 10- and 20-days post-eclosion were performed using inductively coupled plasma-mass spectrometry (ICP-MS), supported by unsupervised pattern recognition techniques. A total of 36 trace elements, including heavy metals and rare earth elements (REEs), were identified as being associated with TRWPs. Element transfer from contaminated food to beetle tissues was observed, with accumulation of essential (Na, Mg, Zn, Ca, Ni), and non-essential (Ba, Al, V, Cr, Fe, As, Ga, Pb, Cd) elements and REEs (Gd, La, Nd, Pr, Sm, Y). Our findings suggest that TWRPs may pose a risk of contaminant transfer in the environment, potentially impacting food webs in ecosystems near high-traffic areas