Terrestrial reptiles and plastic pollution: a review

Plastic pollution is ubiquitous in terrestrial ecosystems and poses a growing threat to wildlife; however, terrestrial vertebrates-and reptiles in particular-have received considerably less attention than aquatic taxa. This review synthesizes the available knowledge on interactions between terrestrial reptiles and plastic pollutants, evaluates the methodological approaches used for their detection, and identifies geographical patterns in the research. Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, studies documenting interactions through ingestion and entanglement were analyzed, explicitly excluding aquatic and semiaquatic species. Eighteen studies published between 2001 and 2025 met the inclusion criteria. In total, 34 species of terrestrial reptiles were associated with plastic pollution, of which 11.7% are listed as threatened. Ten studies were related to microplastics, but only six studies assessed the presence of microplastics using infrared spectroscopy techniques, including Fourier-transform infrared spectroscopy (FTIR), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and micro-Fourier transform infrared spectroscopy (µFTIR). Some of these studies included contamination controls and blank samples. PET (polyethylene terephthalate) was the most frequently identified polymer. Associated effects included internal injuries, gastrointestinal obstructions, physiological impairment, behavioral changes, and confirmed mortality in three individuals. The research focused primarily on Asia, with limited representation from South and North America. Critical knowledge gaps related to sublethal effects, trophic transfer, and contamination of nests or burrows are highlighted, and the need for standardized monitoring frameworks to adequately assess risks to terrestrial reptiles is emphasized.