Microplastic fibres (MPFs) and nanoplastics (NPs) have the potential to be hazardous to soil organisms. Understanding uptake into organisms is key in assessing these effects, but this is often limited by the analytical challenges to quantify smaller-sized plastics in complex matrices. This study used MPFs and NPs containing inorganic tracers (In, Pd) to quantify uptake in the earthworm Lumbricus terrestris. Following seven days exposure, tracer concentrations were measured in earthworms and faeces. Earthworms exposed to 500 μg MPFs/g soil retained an estimated 32 MPFs in their tissues, while at 5000 μg MPFs/g earthworms retained between 2 and 593 MPFs. High variation in body burdens of MPFs was linked to soil retention in earthworms and reduced faeces production, suggesting egestion was being affected by MPFs. NPs uptake and elimination was also assessed over a more extended time-period of 42 days. After 1 day, NPs were no longer detectable in faeces during the elimination phase. However, some retention of NPs in the earthworm was estimated, not linked to retained soil, indicating not all NPs were eliminated. MPFs and NPs uptake can be quantified in earthworms and both particle types can be retained beyond the depuration period, suggesting the potential for longer-term accumulation.

微塑料纤维 (MPF) 和纳米塑料 (NP) 有可能对土壤生物造成危害。了解生物体的吸收是评估这些影响的关键，但这通常受到量化复杂基质中较小尺寸塑料的分析挑战的限制。本研究中使用的MPF和含有无机示踪剂（在，Pd）的纳米颗粒在蚯蚓量化摄取蚯蚓. 暴露 7 天后，测量了蚯蚓和粪便中的示踪剂浓度。暴露于 500 μg MPFs/g 土壤的蚯蚓在其组织中保留了估计 32 MPFs，而在 5000 μg MPFs/g 土壤中，蚯蚓保留了 2 到 593 MPFs。MPFs 身体负荷的高变化与蚯蚓的土壤保持力和粪便产量减少有关，这表明排便受到 MPFs 的影响。NPs 的吸收和消除也在 42 天的更长时间内进行了评估。1 天后，在消除阶段的粪便中不再检测到 NP。然而，估计蚯蚓中的一些 NPs 保留，与保留的土壤无关，表明并非所有 NPs 都被消除。MPFs 和 NPs 的吸收可以在蚯蚓中量化，两种颗粒类型都可以在净化期后保留，