Irreversible Immune Dysfunction in Earthworms from MoS₂Nanosheet Exposure: Implications for Nanoenabled Agricultural Sustainability

Nano-MoS₂ is emerging as a promising agricultural nanomaterial. However, nanoenabled agriculture must balance the proposed benefits with potential risks associated with material incorporation into soil matrices. This work establishes a full-process risk assessment profile for MoS₂ encompassing precursor particles, exfoliated nanosheets, and dissolved ionic species using the soil invertebrate Eisenia fetida under exposure-recovery cycles. The results showed that although precursor MoS₂ exposure at 5–50 mg Mo/kg for 7 days significantly activated (p < 0.001) earthworm lumbrokinase (9.4%), antimicrobial peptide (10.2–14.0%), and hemolysin (11.9%) levels compared to the control, the biota exhibited transient immune memory and persistence upon another 7 days of recovery. Once exfoliated to nanosheet form at a consistent 5–50 mg Mo/kg dose range, more pronounced ion release (3.8–6.4%) and prolonged in vivo accumulation (43.9–55.4% excluded) of MoS₂ nanosheets mediated persistent immune-related gene initiation. Importantly, the filamentous extension of external DNA between immune cells and deterministic clustering of endosymbiotic microbial communities were shown to collaboratively establish the in vivo homeostasis after MoS₂ nanosheet exposure. These findings mechanistically demonstrate the persistent stress on soil invertebrate immune systems under MoS₂ nanosheet exposure and highlight the need to link nanoenabled agriculture to soil eco-sustainability.