Plastic Waste Threatening Lakes, Study Suggests

Plastic waste poses an ever-increasing problem facing the world's oceans where fragile ecosystems are threatened by products that are essentially non-biodegradable. The Western and Eastern Pacific Garbage Patches, for instance, represent the world's largest landfills and are made up almost entirely of plastic, according to some estimates.

Now, research published in the journal Current Biology identifies significant amounts of the same pollutants in Lake Garda, located in the foothills of the Italian Alps.

The researchers chose the lake assuming it would represent a relatively plastic-free body of water based on its subalpine location. They were surprised then when they uncovered a similar number of microplastic particles in comparison to studies of samples taken from marine beach sediments.

These microplastics, the researchers warn, are likely making their way into the food web as they are ingested by a variety of freshwater invertebrates, initiating a journey that could lead all the way to humans. This was further underscored by lab experiments demonstrating the willingness of a range of freshwater invertebrates, including worms and water fleas, to consume artificially ground fluorescent microplastics.

"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," Christian Laforsch of the University of Bayreuth in Germany said in a statement. "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."

The findings are not only relevant to Italians, the researchers argue, warning that the state of the lake does not bode well for others throughout the world.

"The mere existence of microplastic particles in a subalpine headwater suggests an even higher relevance of plastic particles in lowland waters," Laforsch said.

The scientist said more research and standardized surveillance guidelines for controlling microplastic contamination in freshwater ecosystems is needed.