Assessing Microplastic and Nanoplastic Accumulation in Bird Lungs Using Py-GC–MS and LDIR Chemical Imaging

A multidisciplinary team from Sichuan University, Chengdu Tianfu International Airport (both Chengdu, China), and the University of Texas at Arlington (Texas, USA) has investigated the presence of microplastics and nanoplastics in the lungs of 51 species of wild birds using laser direct infrared (LDIR) and pyrolysis gas chromatography–mass spectrometry (Py-GC–MS). The study was published in the Journal of Hazardous Materials (1).

A close up of a pelican's eye and beak, highlighting intricate textures and vibrant details. © Ghulam Siddique - stock.adobe.com

Microplastics and nanoplastics are pervasive environmental pollutants resulting from the breakdown of larger plastic waste and the release of tiny plastic particles from consumer products. These particles, measuring less than 5 millimeters (microplastics) and even smaller (1 µm) for nanoplastics, have been detected in oceans, freshwater systems, soil, and even the atmosphere. Due to their small size, they can be ingested by wildlife, entering the food chain and potentially posing risks to human health.

Birds have long been seen as indicators of environmental health (2). In past research, bird feathers have been used as an indicator of heavy metal exposure (3). As a highly mobile species, they offer scientists a good overview of exposure to microplastics and nanoplastics. Birds also possess a unique respiratory system that increases their exposure to airborne pollutants. The team analyzed 56 wild birds from 51 species collected at Chengdu Tianfu International Airport in China. These birds were acquired through an airport wildlife management program designed to minimize the risk of bird strikes (1). Utilizing LDIR and Py-GC–MS, they detected and quantified microplastics and nanoplastics within the birds' lung tissues.

Microplastics were found in all examined species, with the LDIR analysis revealing different degrees of microplastic contamination in bird lungs, with an average abundance of 221.20 items per species and an average of 416 particles per gram of lung tissue. The most common polymers identified were chlorinated polyethylene, used in the cable and rubber industries, and synthetic butadiene rubber, commonly used in tire manufacturing and shoes. Py-GC–MS detected nylon 66 (PA66), polyvinyl chloride (PVC), and polypropylene (PP) NPs at varying concentrations. Of note is terrestrial, carnivorous, and larger-bodied birds exhibited higher microplastic burdens compared to their aquatic and smaller counterparts, probably because of scavenging.

The detection of microplastics in bird lungs highlights the widespread distribution of airborne plastic pollution and raises concerns about its effects on wildlife and human populations. Microplastic accumulation in bird lungs could lead to respiratory distress, inflammation, and potential long-term health effects such as reduced lung function or increased susceptibility to disease.

With the analysis of microplastics in the air a new avenue of investigation, the study emphasizes the need for stronger regulations on plastic waste management; policies limiting plastic production and enhancing recycling efforts could mitigate microplastic pollution at its source. Environmental agencies could incorporate microplastic analysis into routine air quality assessments to better understand exposure risks. Further research on human exposure could provide insights into the potential health risks posed to mankind.

This study presents the first comprehensive multi-species investigation of its kind, offering direct evidence of nanoplastic exposure in wild birds and emphasizing their potential as bioindicators of airborne microplastic and nanoplastic pollution (1). It serves to highlight the pervasive nature of microplastic pollution and how important it is to mitigate its impact on both wildlife and human populations.

References

(1) Wang, M.; Zhou, P.; DuBay, S.; et al. Assessing Microplastic and Nanoplastic Contamination in Bird Lungs: Evidence of Ecological Risks and Bioindicator Potential. J Hazard. Mat. 2025, 487, 137274. DOI: 10.1016/j.jhazmat.2025.137274

(2) Environmental Science.org https://www.environmentalscience.org/birds-environmental-indicators (accessed 2025-03-31).

(3) Pilastro, A.; Congiu, L.; Tallandini, L.; Turchetto, M. The Use of Bird Feathers for the Monitoring of Cadmium Pollution. Arch. Environ. Contam. Toxicol. 1993, 24, 355–358. DOI: 10.1007/BF01128733