
Humans produce more than 400 million metric tons of plastic annually, with much of it clogging our oceans. New research illuminates just how damaging this can be to seabirds, including scarring, inflammation and organ failure.
To a bird, fish or other creature, plastic may resemble food and they may swallow it, not knowing any better. But depending on their size and shape, plastic chunks can shred the insides of animal digestive tracts. Over time, the resulting scarring adds up, causing a disease called fibrosis, which is named because it results from excessive collagen fibers. It can choke organs, obstructing blood flow and causing them to break down. This damage is seemingly irreversible.
Scientists now have a name – “plasticosis” – for the health problems that stem from animal plastic consumption.
While large shards of plastic can lacerate organ walls, the smaller particles, known as microplastics, can be just as deleterious. Measuring somewhere between 1 and 5 millimeters small, or about 10 to 50 times the width of a human hair, microplastics can more easily enter the bloodstream and accumulate in tissues and organs. They can also break down even further into nanoplastics, which can slip across the membranes of cells, wreaking havoc on their internal functions.
In a recent study – a new, first of its kind study – in the Journal of Hazardous Materials, a team of conservation biologists analysed the digestive tracts of 30 freshly dead seabirds from Lord Howe Island, Australia. They dissected a glandular organ in the birds called a proventriculus, which functions essentially like the first part of the stomach of other animals. Before anything enters a bird’s gizzard, an organ for grinding up food, the proventriculus secretes digestive enzymes and hydrochloric acid to break down meals.
“We identified significant evidence for widespread plastic-related scar tissue formation in the proventriculus of wild seabirds,” the authors wrote in what is likely the first study to thoroughly document plastic-induced fibrosis in wild organisms. They call this disease plasticosis, which is comparable to asbestosis and silicosis, two diseases also caused by inhaling foreign particles (asbestos and crystalline silica dust respectively.)
– Edited excerpts from an article of the same title in Salon (8 March 2023)
Read the original article here:
https://www.salon.com/2023/03/08/birds-are-eating-way-too-much-plastic/