Modulation of chlorpyrifos toxicity to soil arthropods by simultaneous exposure to polyester microfibers or tire particle microplastics

Synthetic fibers released from sewage sludge and tire particles traffic are among the most common types of microplastics in soil. In soil, may interact with chemicals, such as plant protection products used agriculture. Most studies on interactions chemicals focused aquatic environments only few addressed soil arthropods. To increase understanding combined effects arthropods, we studied polyester toxicity insecticide chlorpyrifos. Springtails (Folsomia candida) woodlice (Porcellio scaber) were exposed Lufa 2.2 to a range chlorpyrifos concentrations (0.0088–0.8 0.2–3.9 mg kg−1 dry respectively) without or 0.05 % w/w (“low”) 0.5 (“high”) microplastics. Tire reduced lethality springtails (LC50 = 0.13–0.14 soil) isopods 1.6 by factor 2- > 2.5 chlorpyrifos-induced inhibition acetylcholinesterase (AChE) activity changes electron transfer system (ETS) P. scaber 2–4. Polyester AChE 2 increased >3. The did not affect survival reproduction F. candida. These results indicate that bioavailability be decreased microplastics, especially particles. This study shows importance applying mixture approach for threats but also suggests organism endpoints chosen crucial interpretation exposures chemicals.