Persistent Plastic

Plastic tends to make up a large part of ocean debris. Since plastic is buoyant, or able to float, it can easily travel long distances on ocean currents. In addition to being buoyant, plastic is also persistent. That means it lasts a very, very, very long time without naturally breaking down or decomposing into smaller particles or tiny pieces. Another way of saying this is that plastics do not biodegrade. Bio means "life," and degrade means "to break down." When something is biodegradable, it means it is made from something natural that was once alive (either a plant or an animal.) It also means it can decompose and return to the natural elements or naturally occurring materials found on Earth. Most plastic is made from petroleum, or oil, which is not biodegradable. Therefore, it can take 500 years for a piece of plastic to wear down into smaller particles! And even then, it still doesn't return to a natural element. It just becomes a very tiny piece of plastic.

Another source of plastics in the ocean are nurdles. These are small plastic pellets, or balls, that get melted down to make a variety of plastic products. Nurdles cause big problems! They often end up in the ocean where animals will eat them and get sick from the poisonous chemicals that nurdles contain. Nurdles also damage the bodies of fish, which makes it hard for them to breathe through their gills.