Scientists have identified a new fibrotic disease called “plasticosis” in flesh-footed shearwaters, a species that inadvertently consumes plastic.
They found that plasticosis was even present in shearwaters with only a small quantity of plastic in their stomachs.
While this plastic-related disease has thus far only been identified in flesh-footed shearwaters, experts say that nearly every organism — including humans — is being impacted by plastic in some way.
When flesh-footed shearwater chicks hatch from their eggs, their parents start working to fill the chicks’ stomachs with as much food as possible. They do this for about 80 to 90 days, regurgitating squid and fish into their chicks’ mouths. If all goes to plan, the chicks will grow into fledglings with feathers that will help them fly thousands of miles across the ocean. But as the world’s oceans have filled with microplastics — tiny plastic particles that shearwaters can easily mistake for food — fledglings are getting stuffed full of plastic instead of food. The outcome isn’t good, according to experts.
Scientists studying flesh-footed shearwaters (Puffinus carneipes) have long known that plastic consumption can lead to problems like reduced body condition, organ damage, and ultimately an early death. Now, new research in the Journal of Hazardous Materials shows that consumed plastic can also lead to a newly identified disease: a plastic-related fibrosis aptly called “plasticosis.”
While this disease has thus far only been identified in flesh-footed shearwaters, experts say that nearly every organism — including humans — is being impacted by plastic in some way due to its proliferation in our environment and our ever-increasing exposure to it. One expert calls flesh-footed shearwaters the “canary in the coal mine,” forewarning us of what could happen to our own health if plastic production continues to accelerate as predicted.
Researchers have identified a new plastic-related disease in flesh-footed shearwaters called “plasticosis.” Image by David Cook / Flickr (CC BY-NC 2.0).
‘All these pieces of plastic’
Plastic is everywhere. It’s in our clothing; it packages our food and drinks; it flakes off our car tires. Few plastic products can actually be recycled, and most of it ends up in our environment, either directly as microplastics, such as fibers shed from synthetic clothing, or as larger pieces that eventually break down into smaller pieces. This plastic pollutes the land, water and even the air, and ends up in our food, water, and ultimately our bodies. Many plastics contain toxic chemical additives, but plastic can also act as a sponge attracting other toxic substances, endangering any organism that consumes it.
In the oceans alone, scientists suggest there are now about 170 trillion pieces of plastic — and there could be even more in the future as plastic production continues to proliferate. It’s estimated that there are currently about 450 million metric tons of plastic produced each year, and production is projected to double by 2045.
While previous research has looked at the impacts of plastic consumption on wildlife in a lab setting, this new study claims to be the first to “document and quantify plastic-induced fibrosis in wild organisms.”
The research is based on a sample collection of 21 dead flesh-footed fledglings taken from Lord Howe Island, a small, sock-shaped island about 700 kilometers (430 miles) off the coast of Sydney, Australia. The remote island hosts a large breeding colony for the species. While some of the fledglings were found dead, others were humanely euthanized due to “extremely low body mass.” Most of these fledglings had plastic in their stomachs. On average, each bird contained about 30 pieces, but some held up to 200, the study found.
When the researchers analyzed the birds’ proventriculus, a part of the stomach responsible for digestion, they found that most of the birds had scar tissue indicative of plastic-related fibrosis, or plasticosis.
”All these pieces of plastic, they’re creating little injuries within the stomach,” Hayley Charlton-Howard, the lead author and researcher in Adrift Lab, tells Mongabay. “The stomach is trying to repair those injuries by layering it with a level of scar tissue to help it maintain structural integrity while it’s healing. But if the entire stomach is injured, then the entire stomach becomes really, really heavily scarred, and that’s called fibrosis.”
Once a seabird develops plasticosis, its ability to digest and process foods is reduced. The bird could also have trouble deriving nutrients from its food and be unable to fight off infection or parasites. It’s not currently known if shearwaters can survive for long periods of time with this condition.
Tissue affected by plasticosis (left). Healthy tissue (right). Image by Hayley Charlton-Howard.
The researchers also determined that it was plastic itself that was causing this issue, not other sharp objects like large squid beaks or pumice rocks that flesh-footed shearwaters normally eat. While the reasons for this impact needs to be further investigated, Jack Rivers-Auty, study co-author and human biologist and immunologist at the University of Tasmania, says he believes that plastic triggers an inflammatory response due to its chemical composition.
Rivers-Auty says he was also “completely blown away” by how severe and extensive the fibrotic scarring was in response to the plastic and how quickly the scarring took over the stomach. “The scarring was everywhere,” he says.
The researchers say one point of concern is that plasticosis was even present in birds with only a small quantity of plastic in their stomachs.
“It could be that the birds were able to rid themselves of the plastic somehow, so we couldn’t count that, but we could still see the scarring,” Charlton-Howard says. “Or it may be that just one piece of sharp plastic just bouncing around in the stomach can cause that level [of damage]. We just don’t know.”
Therese Karlsson, the science and technical adviser at the International Pollutants Elimination Network (IPEN), who was not involved in the study, says the research is “very important” because it “gives a name to something that has been discussed within the scientific field for a long time.”
“As the authors note, there has been a lot of previous studies indicating that this might be a possibility,” Karlsson tells Mongabay. “So although it is not surprising, it is concerning that we now know that it can happen in the field.”
