Scientists Finding Plastic Pollutants in Global Waters

A photomicrograph of PHA microbeads created at VIMS. Scale is in microns (millionths of a meter). Photo by Jason McDevitt, Applied Research Center

Microplastics have become a big concern in the world’s oceans and estuaries.

Water pollution remains a significant problem in bodies of water large and small worldwide; however, in addition to the visible plastic litter, the even larger problem are small pieces of polyethylene or polypropylene referred to as microplastics, which international researchers acknowledge as a significant threat to water and aquatic ecosystems.

Researchers at the Virginia Institute of Marine Science (VIMS), College of William & Mary, say that one of the two primary sources of microplastics they found are substances known as “microbeads” — present in scores of household products such as toothpaste, sunscreen, shampoo, soap, and moisturizers.

Kirk Havens, a Virginia Institute of Marine Science researcher, states:

Microplastics have become a big concern in the world’s oceans and estuaries. We already know that larger plastic items can harm organisms like turtles, seabirds, and fish by interfering with digestion or through strangulation; a concern with microplastics is that they’re even more widely dispersed, and small enough to be eaten by a much more diverse group of organisms. Once ingested, these compounds and anything they’ve absorbed can be magnified up the food chain.

Rob Hale, a professor at Virginia Institute of Marine Science and an expert on marine toxic chemicals, says some small plastic particles absorb organic pollutants such as polychlorinated biphenyls (PCBs) and DDT. They have reportedly been found in the small bits of plastic in marine worms, tiny crustaceans, and filter feeding animals, such as mussels and barnacles. Hale adds:

Depending on their size and composition, plastics may release previously bound-up chemicals into the water as they break into particles. At the same time, limited researchsuggests the changing composition of the smaller plastic bits may make it easier for them to absorb other chemicals that may be in the water. […] When something comes along and eats [a piece of microplastic], they have basically ingested a pill of chemicals.

Microplastic pollution is also a problem in freshwater lakes, say researchers from École Polytechnique Fédérale de Lausanne (EPFL). They reported detecting surprising amounts of microplastic pollution in Lake Geneva, which is one of the largest lakes in Western Europe.

They found pieces of plastic waste up to 5mm in diameter in the waters of the lake, which surprised them, given “the massive efforts put into protecting the lakes shores over the past decades, both on its French and the Swiss shores.” In sampling the beaches, they found plastic in each and every sample.

The debris included polystyrene beads, hard plastics, plastic membranes, and pieces of fishing line. The researchers say this leads them to believe that similar conditions exist in other freshwater bodies worldwide.

The EPFL researchers also surmise:

Microplastics in continental waters may be the main source of microplastic pollution in oceans, where huge hotspots containing high concentrations of these pollutants have formed. Scientists estimate that only around 20 percent of oceanic microplastics are dumped straight into the sea. The remaining 80 percent are estimated to originate from terrestrial sources, such as waste dumps, street litter, and sewage.

The researchers say that “the full extent of their consequences in lakes and rivers is only now being investigated,” and have had their recent findings published in the latest issue of the journal Archives des Sciences. The Swiss Federal Office for the Environment is also extending its research to an exploration of lakes and rivers across the country that will survey the pollution in lakes, rivers, and biota plus the levels of micropollutants, such as PCBs, which, they say, “have already been found stuck on microplastics from Lake Geneva in significant concentrations.”

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