SAUSALITO, Calif. -- A small enzyme could be the solution to plastic pollution, one of the planet's biggest environmental problems. Millions of metric tons of plastics wind up in the ocean each year.

Researchers at the University of Portsmouth in Great Britain may have come up with a solution. They figured out a way for a natural enzyme to digest strong plastic commonly used in bottles, CBS SF Bay Area reports.

"What's really special about this enzyme: it digests something man-made," said professor John McGeehan.

Magnified images, sped up, show the enzyme breaking down the plastic into its two key ingredients.

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"Most enzymes are digesting maybe grass stains or things like that in your clothing," said McGeehan. "But this material has only existed for the last 50 years, so to have an enzyme involved that actually eats this man-made material is really stunning."

It usually takes decades, if not centuries, for plastic bottles to break down. With the enzyme, the process takes just a few days.

But environmentalists said there's still a long way to go since the enzyme only works on one type of plastic.

Scientists are now working to improve the enzyme so that it works on a large scale.

In the San Francisco Bay Area, the impact of plastic pollution is clear. The Marine Mammal Center said they treat 10 to 20 animals each year who are either injured or have ingested ocean garbage.

Adam Ratner, manager at the Marin Mammal Center in Sausalito, pointed at several plastic nets that were taken from inside a 51-foot long whale that washed ashore Tomales Bay in Point Reyes National Seashore. The whale died after ingesting 450 pounds of ocean trash.

"All of these nets that you see hanging behind me actually come from the inside of that sperm whale's stomach, and allow us to see the issue of nets," Ratner said.

"Whether it's a sea lion that we have at a hospital right now named Tyrell, that had a plastic packing strap around its neck, or animals that have ingested balloons -- it's unfortunately something we do see here in the Bay Area," said Ratner.