Toxicological and Environmental Risk Assessment of Biopolymeric Coatings for Horticultural Produce: A Comprehensive Review on Biosafety, Degradation, and Ecological Risks

The increasing adoption of biopolymeric and nanostructured coatings for horticultural produce has emerged as a sustainable strategy to mitigate postharvest losses and extend shelf life. However, while their technological performance has been extensively documented, comprehensive and integrative assessments of biosafety, potential human health implications, and environmental risks profiles are still insufficiently explored. This review critically analyzes recent advances in polysaccharide, protein, and lipid-based coatings, including nanoenabled systems incorporating metallic nanoparticles and bioactive agents. The mechanisms underlying gas barrier properties, antimicrobial activity, and preservation efficacy are discussed alongside degradation pathways in composting, soil, and aquatic environments. Particular attention is given to nanoparticle release, migration potential, gastrointestinal fate, and toxicological endpoints such as oxidative stress, genotoxicity, endocrine disruption, and immunomodulation. Ecotoxicological evidence across trophic levels, from microorganisms and invertebrates to fish and amphibians, is examined, highlighting sublethal and mechanistic biomarkers relevant to environmental risk assessment. Regulatory frameworks from major agencies are also compared to contextualize current safety standards and limitations. Overall, although biopolymeric coatings represent promising alternatives to conventional plastics, their life-cycle impacts, transformation products, and nano-related uncertainties require comprehensive, multilevel risk evaluation to ensure truly sustainable and safe postharvest applications.