From the New York Times article: Pressure Is on to Recycle Water Filters...
http://www.nytimes.com/2008/10/06/business/media/06filter.html?ref=mediaDrew McGowan, a Clorox spokesman, said the cost of a nationwide recycling program would be “absolutely astronomical, and there’s no way any one company can afford to do this.” Nonetheless, a test program may begin within the next year that will let people return the filters to retail stores, he said.

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