Quantification and Characterization of Microplastics in Wildlife Feces: Case Study from Buffer zones of Western Ghats, Tamil Nadu

Abstract

Wildlife is greatly impacted by the presence of microplastics in the environment, which has become a global concern. In order to clarify their possible effects on ecosystem health, this study examines the frequency of microplastics in the feces of wild animals. Indian Elephants (Elephas maximus indicus), sambar Deer (Rusa unicolor), Gaurs (Bos gaurus), and Rabbits (Lepus nigricollis) were the main subjects of this investigation. In Tamil Nadu\'s Coimbatore district, we gathered wild animal excrement from the buffer zones of the Western Ghats range. Twelve animal feces samples included 127 Micro Plastic Particles (MPs) in total. A trinocular microscope was used for qualitative investigation, which showed that MPs came in a variety of colors and forms. Transparent (46 particles) was the most commonly detected color, followed by white (30), blue (15), red (6), light blue (4), brown (3), and pink (3). Fibers (70), pieces (36), and sheets (21) were among the MP shapes that were detected. To determine the kinds of polymeric components contained in the particles, FT-IR analysis was performed using Origin software. Correlations between the overall number of MPS in various animal samples and their colors and shapes were examined using SPSS software.

Introduction

Microplastic (MP) contamination has become a serious global environmental issue, with MPs now detected across marine, freshwater, terrestrial, and even extreme environments such as the Arctic, Mount Everest, and the Mariana Trench. They are also found in indoor air, drinking water, food items, and even human tissues such as the lungs and placenta, demonstrating their pervasive presence. MPs originate from both primary sources (e.g., cosmetics) and secondary sources (degraded larger plastics), spreading through wind, water currents, and poor waste management.

Although much research focuses on aquatic contamination, limited studies have assessed MP presence in wild terrestrial animals. This study investigates microplastic ingestion by wild animals in the Southwestern Ghats buffer zone near Coimbatore, India. Urbanization and reduced natural food availability in the region have forced animals such as elephants, gaur, deer, and rabbits to consume contaminated food and water, resulting in MP accumulation through air, soil, and food chain pathways.

Fecal samples were collected from six locations around Coimbatore and processed using digestion, filtration, density separation, and FT-IR analysis to identify and characterize microplastics. The findings show that all analyzed animals had ingested MPs, with 127 particles detected across 12 individuals. Elephants had the highest MP count, while deer had the lowest. MPs varied in size, shape, and chemical composition, indicating multiple contamination sources.

Conclusion

To assess the presence of MPS in wild animal feces, samples were collected from various mammalian species across different habitats. These samples underwent established methods for MPS extraction and analysis, confirming the presence of MPS in every sample tested. The predominant types of MPS identified included synthetic fibers, fragments, and sheets, varying in size from a few microns to several millimeters. This study highlights the widespread contamination of natural environments with MPS and underscores the need for comprehensive mitigation strategies to address this global issue.These findings highlight the widespread presence of MPS in the environment and their potential uptake by wild animals through ingestion of contaminated food or water. The presence of MPs in wild animal feces raises significant concerns for ecosystem health, as these particles can accumulate in the food chain and adversely affect the health and reproduction of wildlife. Moreover, the detection of MPs in wild animal feces suggests potential human exposure to these contaminants through consumption of wildlife or ingestion of contaminated water sources. Addressing this issue requires concerted efforts to mitigate plastic pollution and safeguard both environmental and human health.This suggests the necessity for comprehensive research and management strategies to mitigate the impacts of MPS on both wildlife and human health. Our study emphasizes the urgent need for further investigation into the sources, distribution, and effects of MPS in wild animal feces. By gaining a deeper understanding of the extent of contamination and its potential consequences, we can advance efforts to develop solutions that reduce the release of MPS into the environment and safeguard vulnerable wildlife populations.In conclusion, the presence of MPS in animal feces serves as a poignant reminder of the widespread nature of plastic pollution and its extensive impacts on ecosystems and human health. Addressing this issue requires concerted efforts at both local and global levels to mitigate plastic pollution and safeguard the health of our planet and its inhabitants. Collaborative actions are essential to effectively reduce plastic contamination and promote sustainable practices for the benefit of current and future generations.

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Copyright © 2025 Arunthathi Elamparuthi, Muniasamy Muniyandi. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.