Advanced materials - Food grade melatonin-loaded Lipid Surfactant Submicron Particles (LSSP)-environmental impacts.

Area of Science:

• Environmental Science
• Toxicology
• Materials Science

Background:

• Lipid-based nanoparticles (LNPs) are advanced materials (AdMa) used in drug delivery.
• Existing toxicological data for LNPs often focus on specific applications and indicate low toxicity.
• The ecotoxicological effects of LNPs remain largely uncharacterized.

Purpose of the Study:

• To investigate the ecotoxicity of a specific Lipid Surfactant Submicron Particles (LSSPs) formulation and a variant (LSSP-xg) on soil invertebrates.
• To assess the impact of LSSPs on the survival, reproduction, and size of Enchytraeus crypticus and Folsomia candida.
• To evaluate potential dose-dependent and long-term ecotoxicological effects.

Main Methods:

• Tested LSSPs and LSSP-xg formulations loaded with melatonin in LUFA 2.2 soil.
• Utilized two soil model invertebrate species: Enchytraeus crypticus (Oligochaeta) and Folsomia candida (Collembola).
• Followed OECD standard guideline (28 days) and extended exposure (56 days), assessing survival, reproduction, and size.

Main Results:

• LSSPs and LSSP-xg exhibited dose-dependent toxicity to both E. crypticus and F. candida, reducing survival and reproduction.
• LC50/EC50 values for 28-day exposure were approximately 30/15 mg/kg for E. crypticus and 55/44 mg/kg for F. candida.
• Reduced size in F. candida was observed, but it was the least sensitive endpoint; toxicity did not increase with longer exposure.

Conclusions:

• The tested LSSPs formulation, despite using food-grade components, poses ecotoxicological risks to soil invertebrates.
• Highlights the need for ecotoxicity assessment of advanced materials (AdMa), even those with generally recognized as safe components.
• Further research is needed to identify specific components responsible for toxicity in complex AdMa formulations for accurate hazard assessment.