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