Plastic Pollution Is So Pervasive That It’s Causing a New Disease in Seabirds

Audubon.org - J. Besl (Reporter)

Researchers coined the term “plasticosis” to describe stomach damage related to ingesting trash.

The word refers to a newly described disease, marked by severe stomach damage from eating little bits of plastic, in a large population of Flesh-footed Shearwaters. While the name currently applies to one population of one species on one island, the risks reach much farther. There are 170 trillion pieces of plastic floating on the ocean surface, and they’re ingested by thousands of marine species.

The findings, published in the Journal of Hazardous Materials, also underscore the scale of the world’s plastic pollution problem. These shearwaters nest not in some heavily developed area, but on remote Lord Howe Island, about 360 miles east of Australia. It’s a UNESCO World Heritage Site surrounded by an Australian Marine Park. Yet, while 75 percent of the island is protected for conservation, plastic still finds its way there.

Previous work by the researchers showed that roughly 90 percent of the island’s Flesh-footed Shearwaters had plastic in their guts. Marine plastics start to smell like food once they’re coated in plankton and algae, luring in birds with a strong sense of smell. That’s why the species is among the most plastic-plagued birds on the planet. 

Jennifer Lavers, a research scientist at Adrift Lab and co-author of the new study, has observed these seabirds for more than a decade, alongside colleagues from the Lord Howe Island Museum and the Natural History Museum of London. She’s seen it all in the stomachs of shearwaters: doll arms, toy fish, plastic pieces stamped with the word “plastic.” But that’s just the recognizable bits. Even millimeter-thick microplastics can cause significant harm as they churn in a bird’s stomach, Lavers says. Once the stomach is scarred, the damage is irreversible.

For the study, Lavers and her colleagues visited Lord Howe Island to examine shearwater stomachs. They collected 30 fledglings that either had recently died or were euthanized due to extremely low body mass. The team completed necropsies in a plastic-free research station to prevent contamination. They counted the ingested plastics in the birds’ stomachs and sent tissue samples back to the lab to look for collagen, the prominent protein in scar tissue. The lab team was expecting to find pockets of regional scar tissue. Instead, it was everywhere.

“I was certainly not expecting for most of my samples to be nearly completely composed of collagen,” says Hayley Charlton-Howard, another researcher at Adrift Lab and co-author on the study.

Stomach scarring from plastic was so prevalent that the researchers decided it needed a name. They chose plasticosis, following the format of silicosis and asbestosis, two irreversible lung diseases similarly caused by inorganic materials. Of note, while the birds consume naturally abrasive pumice stones to help with digestion, the researchers found only plastic led to stomach scarring.

Plastics are indigestible and persist in the digestive tract, continuously scraping the organs of Flesh-footed Shearwaters. That causes several knock-on health effects, Lavers says. Birds feel less hungry. There’s less room for nutrients. A scarred stomach lacks flexibility, so birds are able to transport less fish back to the nest. The damaged organ creates less digestive acid to process food and protect against parasites.

The presence of plastic triggers a “maelstrom of compounding sublethal impacts,” says Charlton-Howard. “The fact that we’re seeing such damage in such a vital organ is really, really concerning.”

The birds aren’t dying directly from plasticosis, but the disease affects their growth, nutrition, and overall health. Lavers recently co-published a study showing the average Lord Howe Island Flesh-footed Shearwater’s wingspan, bill length, and body size have all decreased in just the past 13 years. She has no doubt the change is connected to the plastics taking the space of nutrients in the birds’ stomachs.

Dozens of seabird species are already known to consume plastic, and researchers expect that tally to climb. It’s likely that some of them also suffer from the newly described disease. On Midway Atoll, for example, researchers found 98 percent of Laysan Albatrosses chicks had plastic in their stomachs. That was in 1997. Global plastic production has only increased since then.

“I think there’s every reason that this phenomenon, plasticosis, is likely much more widespread than we yet realize,” says Don Lyons, director of conservation science at Audubon’s Seabird Institute.

There are, however, glimmers of hope for the world’s marine species. The United Nations held its first negotiations on a global plastic treaty this winter. The United Kingdom announced a ban on several single-use plastics in January, joining similar restrictions in Canada, Barbados, and the European Union. Those are important steps, but not enough to curb the problem. If the pace of production doesn’t change, researchers predict the rate of plastics entering the world’s oceans will double between now and 2040.

The researchers hope the name plasticosis contributes to a solution in its own rhetorical way. A shared name allows researchers to rally around a subject and compare notes across species. The word is memorable and media-friendly, said France Collard, a microplastic researcher at the Norwegian Polar Institute, in an email. The study “will certainly open new research perspectives in the field of plastic pollution,” she said.

But a word can only do so much. Ultimately, reducing the world’s reliance on plastic is the preventive treatment for plasticosis. That’s beyond the scope of any one biologist. “It’s really about finding earlier stages of intervention,” Lavers says, “because once you get to this point, there is no turning back.”

Thank you Audubon Society News / J. Besl (Reporter) for this helpful information!