Litter can remain visible for extended periods of time before it eventually biodegrades, with some items made of condensed glass, styrofoam or plastic possibly remaining in the environment for over a million years.
About 18 percent of litter, usually traveling through stormwater systems, ends up in local streams, rivers, and waterways. Uncollected litter can accrete and flow into streams, local bays and estuaries. Litter in the ocean either washes up on beaches or collects in Ocean gyres such as the Great Pacific Garbage Patch. About 80 percent of marine debris comes from land-based sources.
Some litter that is collected can be recycled, however degraded litter cannot be recycled and eventually degrades to sludge, often toxic. The majority of litter that is collected goes to landfills.