Plastic pollution in our seas and oceans has impacted these ecosystems to such an extent that some animals already have plastic in their bodies. A new studypublished this week in sciencedirect, found polymer particles and fibers in the blubber and lungs of marine mammals.
Marine mammals consume large amounts of microplastic particles. They do it through dams that have consumed objects made of this material or directly from the waste thrown into the sea. The study in these animals suggests that microplastics can travel out of the digestive tract and lodge in the tissues.
“Not only are they ingesting plastic and dealing with the big pieces in their stomachs, they are also being internalized,” he said in a release Greg Merrill, lead author of the research and a fifth-year graduate student at Duke University’s Marine Laboratory. “Some proportion of its mass is now plastic.”
The team of scientists obtained samples of 32 animals stranded or collected between the years 2000 and 2021, in Alaska, California and North Carolina. A total of 12 species are represented in the data. Among them, a bearded seal, bottlenose dolphins and several gray whales.
68% of all marine mammals analyzed it had microscopic plastic particles. Polyethylene, a component of beverage containers, was one of the most common materials found in these animals. Also, polyester fibers, used in the textile factory.
The risk to humans from plastic in marine mammals
The study took samples from four tissues: in three types of fat and lungs. Plastic was detected in all. The particles in these tissues ranged on average from 198 microns to 537 microns. To put into perspective, a human hair has a diameter of approximately 100 microns.
Merrill explains that plastic parts can also tear and wear down fabrics. “Now that we know that the plastic is in these tissues, we are looking at what the metabolic impact might be,” the researcher added.
There is also a toxic risk, for these animals and, eventually, for humans. “Exposure could be direct through consumption,” says the report. Either because some people feed on this type of mammal or because they are consuming the same prey as these animals.
Merrill is preparing a next stage of his research, in which he will use cell lines grown from biopsied whale tissue. The objective is to perform toxicology tests on plastic particles.
A 2022 article, published in Nature Communications, estimated that blue whales, the largest creatures on Earth, are ingesting 10 million pieces of microplastic every day. These animals could be swallowing the equivalent of 43 kilos of plastic waste.