A new study published in Science Advances has uncovered alarming health effects of plastic ingestion in seabirds. Researchers analyzed 745 proteins in young sable shearwaters (Ardenna carneipes)—seabirds less than 90 days old that appeared healthy. Shockingly, those with plastic in their stomachs showed signs of neurodegenerative disease, as well as kidney and liver damage.

How Plastic Affects Seabird Health

The study also revealed severe stomach lining damage, likely caused by embedded microplastics. As a result, proteins normally found only in the stomach were detected in the birds’ blood—an indicator of systemic harm.

While these findings don’t directly translate to human health, they provide a disturbing glimpse into the slow, insidious effects of plastic pollution on living organisms.

Hidden but Harmful: The Long-Term Effects of Plastic Exposure

Past studies have shown mixed results regarding plastic’s impact on wildlife. Some found increased exposure to heavy metals, while others reported minimal effects. Why the inconsistency?

Many early studies focused on a single health response, such as body condition. However, real-world exposure is far more complex. A bird’s response to plastic ingestion could depend on various factors, just like how humans may react differently to health tests depending on their condition.

Recent, more detailed research has shown that plastic ingestion can lead to:
High cholesterol levels
Reduced body size and shorter wings
Plasticosis – an inflammatory condition causing scar tissue formation

These issues may not immediately kill the birds, but they reduce their quality of life—similar to how chronic health conditions affect humans.

Proteomics: Unlocking the Hidden Damage

To understand the full impact of plastic, researchers used proteomics, a cutting-edge approach that studies protein composition and function. This method is widely used in medicine but is rarely applied to wildlife research.

Key findings include:

• Low albumin levels – A marker of poor liver function
• Reduced brain-derived neurotrophic factor (BDNF) – A protein crucial for neuron survival and cognitive functions, including the ability to recognize mating songs

These changes suggest that even if plastic exposure doesn’t kill birds, it could impair their cognitive abilities, reproductive success, and long-term survival.

Plastic Pollution Affects More Than Just the Stomach

The study found that plastic’s impact extends beyond the stomach. Health damage was detected in the liver, kidneys, spleen, and brain, indicating whole-body consequences of plastic ingestion. Scientists believe they have only scratched the surface of understanding the full extent of these effects.

What Does This Mean for Wildlife and Humans?

The most concerning part? These alarming health issues were found in very young birds that looked completely healthy. This raises urgent questions:
How many other species are suffering from similar, undetected health impacts?
Could microplastics be affecting human health in ways we don’t yet understand?

Future research will need to tackle these questions, but gathering such data is an enormous challenge. Even after a decade of research, scientists have only begun to map out the complexity of this issue in a single bird species.

For humans, the health effects of plastic exposure may be difficult to quantify due to the countless environmental and lifestyle factors at play. However, this study provides a clear warning—plastic pollution is causing long-term harm, even if the effects are not immediately visible.

The Takeaway: Listen to What Seabirds Are Telling Us

This research highlights the silent but devastating consequences of plastic pollution. Seabirds are sending us a clear message—it’s time to take action before it’s too late.

More information:
Alix M. de Jersey et al, Seabirds in Crisis: Plastic Ingestion Induces Proteomic Signatures of Multiorgan Failure and Neurodegeneration, Science Advances (2025). DOI: 10.1126/sciadv.ads0834