Exploring the impacts of microplastics and associated chemicals in the terrestrial environment – Exposure of soil invertebrates to tire particles

Abrasion of tire wear is one the largest sources microplastics to environment. Although most particles settle into soils, studies on their ecotoxicological impacts terrestrial environment are scarce. Here, effects (<180 μm) three ecologically relevant soil invertebrate species, enchytraeid worm Enchytraeus crypticus, springtail Folsomia candida and woodlouse Porcellio scaber, were studied. These species exposed spiked in or food at concentrations 0.02%, 0.06%, 0.17%, 0.5% 1.5% (w/w). Tire contained a variety potentially harmful substances. Zinc (21 900 mg kg−1) was dominant trace element, whilst highest measured organic compounds detected for benzothiazole (89.2 kg−1), pyrene (4.85 chlorpyrifos (0.351 HCB (0.134 methoxychlor (0.116 BDE 28 (0.100 kg−1). At test concentration (1.5%), decreased F. reproduction by 38% survival 24%, acetylcholinesterase (AChE) activity P. scaber 65%, slight decrease E. crypticus not dose-dependent. In food, reduced 38%. results suggest that micro-sized can affect invertebrates found roadsides, short-term further from roadsides unlikely.