Ocean Plastic Pollution Found to Disrupt Hormones in Northern Fulmars
Ocean plastic pollution is already a well-known environmental crisis, but new scientific research adds an alarming dimension to the issue. A groundbreaking study published in the journal Environmental Pollution has confirmed that plastics ingested by northern fulmars, a common seabird found in the North Atlantic and North Pacific Oceans, release harmful chemicals that disrupt hormone function.
Seabird Health at Risk from Endocrine Disruptors in Plastic
Researchers from the University of California, Santa Cruz and San Diego Zoo Wildlife Alliance discovered that chemicals leached from swallowed plastics can interfere with the birds’ endocrine systems. This hormone disruption can negatively affect fertility, development, behavior, and overall survival, with serious implications for biodiversity and marine food chains.
This marks the second collaborative study between the two institutions linking marine plastic pollution to endocrine disruption in wild seabirds.
“We’ve long known that plastic ingestion can cause physical harm to seabirds, but this study shows it may also have hidden biological effects,” said Liesbeth Van Hassel, the study’s lead author.
First Species-Specific Hormone Disruption Evidence in Seabirds
What makes this research significant is that it provides the first species-specific evidence of hormone disruption in wild seabirds caused by plastic ingestion. Using cloned hormone receptors from northern fulmars, researchers tested chemicals extracted from plastic pieces found in the birds’ stomachs. The results were startling:
- 48% of tested fulmars (13 out of 27) carried plastic that either activated or blocked hormone receptors.
- The chemicals mimicked reactions seen in human hormone receptors, suggesting cross-species risks.
- The disruption was not linked to the type of plastic, but rather to chemical additives such as BPA and phthalates—known endocrine disruptors in humans and animals.
Continuous Exposure to Toxic Plastic Additives
In laboratory tests, some plastics continued to leach active hormone-disrupting chemicals for over two weeks. According to Christopher Tubbs, co-author and Associate Director of Reproductive Sciences at San Diego Zoo Wildlife Alliance, this suggests that seabirds receive a steady, internal exposure to toxic compounds, compounding the risk over time.
“Seabirds aren’t just ingesting harmful plastic—they’re getting a continuous dose of hormone-altering chemicals,” said Tubbs.
Implications for Marine Wildlife Conservation
This study highlights a hidden danger of plastic pollution: its chemical impact on wildlife. The findings underscore the urgency of addressing plastic waste in oceans—not only to prevent physical harm but also to mitigate invisible biological threats that could disrupt entire ecosystems.
Continued Conservation Research and Collaboration
This critical research was made possible through the partnership between San Diego Zoo Wildlife Alliance and UC Santa Cruz. Their joint efforts aim to uncover overlooked threats to marine species and to inform global wildlife conservation strategies through science.
Reference:
Hormonal disruption from plastic ingestion in northern fulmars: Activation and inhibition of estrogen receptors. Environmental Pollution (2025).
DOI: 10.1016/j.envpol.2025.126145
Provided by:
San Diego Zoo Wildlife Alliance