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In recent years, numerous municipalities in the United States and abroad have implemented either mandatory or voluntary curbside recycling programs. In most of these programs, household trash is sorted into paper, metal (steel and aluminum), and plastic products prior to its collection and then transported for processing into recycled materials. While the materials are not recycled at the curbside, the term curbside recycling generally now represents both the collection and sorting phases for these household materials.

Before we get into specifics, please note that this particular article will only address the third R of solid waste management--recycling--and not reducing or reusing materials (3Rs = reduce, reuse, recycle). These three processes are all means by which waste generation is decreased, but each is distinctly different from the others. The definition of recycling is limited to the collection of existing materials or products that are then used as the raw source, or stock, for the production of new materials. The materials collected are diverted from the waste stream, thus decreasing the total amount of solid waste generated.


This article was originally published in Science Scope, volume 30, issue 4, in 2006.

Peer Reviewed



National Science Teachers Association



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