Scientists at the Woods Hole Oceanographic Institute, USA, have concluded that microplastic is not the biggest problem with plastic bag and bottle degradation. Research has shown that sunlight doesn't just “break down” plastics in the ocean, it can convert their base polymers and additives into a mixture of new and highly hazardous chemicals.
Scientists definitely do not like plastic, but it turned out that it is much worse than they previously thought.
As part of their work, the scientists studied how the sun's rays affect ordinary plastic bags from supermarkets (they took samples from Target and Walmart). They also examined Goodfellow LDPE bags.
All packages were divided into groups depending on the content of certain organic substances and metals. The samples were placed in sterilized beakers filled with ionized solution to simulate immersion in seawater.
Half of the glasses were removed to a dark room, while the rest were left in a temperature-controlled cell for five days, in which the "artificial sun" was constantly shining.
It was found that the samples left in the dark released a small amount of dissolved organic compounds into the saline solution. However, those that remained in the light were simply bathed in new chemicals! Having studied the composition of the "solar solution", the authors of the work discovered tens of thousands of dissolved organic compounds, and all of them appeared in only 5 days.
The authors of the work summarize that the process of plastic disintegration is actually ten times more complicated than we always thought. It leaves behind a lot of toxic materials that weren't even considered a problem before. “We need to think not only about the fate and impact of the original plastics on the environment, but also about the transformation of these materials,” the scientists write.