In the center of the Pacific Ocean, the infamous “Great Pacific Garbage Patch” collects millions of tiny bits of plastic. The massive floating dump gets all the attention, but freshwater lakes may have their own plastic pollution problems.
A recent study found numerous particles of plastic in a seemingly pristine lake in the foothills of the Italian Alps. Sediments from Lake Garda, Italy’s largest lake, contained shreds of plastic ranging from recognizable litter to microscopic bits. The lake’s sediments contained as much plastic as some beach deposits.
The big chunks detract from the natural beauty and could harm wildlife, but the microscopic particles could be truly insidious. Tiny animals can ingest the plastics and pass them on to larger animals, including humans.
“Next to mechanical impairments of swallowed plastics mistaken as food, many plastic-associated chemicals have been shown to be carcinogenic, endocrine-disrupting, or acutely toxic,” said study author Christian Laforsch of the University of Bayreuth in Germany in a press release. “Moreover, the polymers can adsorb toxic hydrophobic organic pollutants and transport these compounds to otherwise less polluted habitats. Along this line, plastic debris can act as vector for alien species and diseases.”
In lab experiments, Laforsch and his team tested the potential for lake invertebrates to start the chain of passing plastic through the food web. They found that tiny freshwater animals, such as water fleas, will indeed devour the plastic.
Laforsch hadn’t expected to find such a heavy load of plastic in the azure waters of subalpine Lake Garda.
“The mere existence of microplastic particles in a subalpine headwater suggests an even higher relevance of plastic particles in lowland waters,” Laforsch said.
As an occasional fisherman and frequent pescavore, I wonder how much plastic makes its way into the lakes and ponds here in Missouri…and how much of that plastic ends up in me. When I eat fresh-caught, local fish, it seems clean and safe. Perhaps, I have actually been eating bits of plastic along with my bass.
IMAGE: A view of Lake Garda, Italy. (Thomas Cristofoletti/Getty Images)