'Pristine' Subalpine Lake in Italy Contaminated by Hazardous Plastics

Subapline lakes look beautiful and pristine at first glance. They appear clear and sparkling, overshadowed by rocks and surrounding mountains. It turns out, though, that these lakes aren't as pristine as we might think. Scientists have discovered that these bodies of water may be contaminated by potentially hazardous plastics.

Tiny microplastics are a huge issue in the environment. These tiny bits of plastic are actually known to coat the surface of the ocean in a thin film. Consumed by fish and other species, these plastics can make it into the food chain. Now, though, it turns out that microplastics aren't just a problem for the world's oceans.

"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 Christian Laforsch, one of the researchers, in a news release. "Moreover, the polymers can absorb 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 this case, the researchers examined Italy's Lake Garda in order to investigate freshwater contamination with micro- and macroplastics. They assumed that it would be less polluted due to its subalpine location. What they found, though, was the opposite. It turned out that the numbers of microplastic particles in sediment samples were similar to those found in studies of marine beach sediments. In fact, the researchers discovered that the size and range of microplastics probably meant that they might find their way into organisms living in the lake. In the lab, the researchers even showed that freshwater invertebrates that ranged from worms to water fleas would ingest artificially ground fluorescent microplastics.

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

The findings reveal the importance of properly disposing of plastics. In addition, it shows that areas that are thought of as "pristine," really aren't as unpolluted as people might think. As the microplastic burden continues to grow in waterways, it's also important to understand how the chemicals within plastics could impact local wildlife and, in turn, humans.

The findings are published in the journal Current Biology.