Effect of Multi-Walled Carbon Nanotubes in the Snail Cornu aspersum

The progressive commercial deployment of multi-walled carbon nanotubes (MWCNTs) raises concerns about their terrestrial ecotoxicity. We exposed adult Cornu aspersum (150 snails; five replicates of three animals per time-point) to 50 mg L−1 MWCNT-dosed Lactuca sativa for 30 days and quantified five mechanistic biomarkers alongside survival. Hemocyte spread-cell area increased by 48% (from 243 ± 22 µm2 at day 0 to 360 ± 18 µm2 at day 14, p < 0.001). Lysosomal membrane stability (neutral red retention) fell twofold within 72 h and to 10 min by day 30 (controls ≈ 60 min), indicating early, persistent destabilization. Micronucleus frequency rose above the ecogenotoxic threshold of 5‰ after 7 days, peaking at 8.3 ± 0.7‰ on day 14 (p < 0.01). Hepatopancreas metallothionein concentrations doubled by day 3 (2.1 ± 0.3 vs. 1.0 ± 0.2 µg g−1 ww in controls) and remained >150% of control throughout exposure, consistent with metal impurity mobilization. Acetylcholinesterase activity in cephalic tissue declined by 50% after 7 days and by 73% after 30 days, revealing sustained neurotoxicity. Despite these pronounced sub-individual disturbances, cumulative mortality reached only 19% at day 30, suggesting substantial, but finite, physiological compensation. Collectively, the data demonstrate that a 50 mg L−1 dietary load of MWCNTs elicits rapid cytotoxic, genotoxic, and neurotoxic responses in C. aspersum that precede overt lethality, underscoring the utility of this gastropod and the chosen biomarker suite for monitoring nanotube contamination in agro-ecosystems and food-grade snail farming.