Ever since it was introduced in 1976, VHS tape has steadily and inexorably beaten a path from personal video collections to the landfill. And the pace has quickened noticeably lately, with DVDs increasingly pushing VHS aside.

Consumer discards, though, are just the tip of the tape-waste iceberg. Film studios, postproduction facilities, video duplication companies and other industry enterprises are dumping tapes faster than Disney can shed Miramax movies.

The question is: What happens to that fast-growing mass of obsolete plastic?

Quick answer: It’s recycled – in a way. The tapes, which are not biodegradable, arrive 5,000 to 10,000 a day at Tropical Media in Burbank, Calif. Tropical – and companies like it – hire independent recycling companies to break down the cassettes in Mexico by stripping the plastic and screws off the tapes. Then the tapes are shipped back to be erased by degaussing – a process of demagnetizing that strips away the recorded information – protecting privacy and intellectual property rights and, some believe, enhancing tape quality. The newly blank tapes are then resold.

A good-quality VHS tape can be reused about 20 times if stored correctly, experts say. Lesser-quality ones begin to show glitches after only a few recordings.

Given that it takes one-sixth of a gallon of petroleum to produce a single half-inch VHS tape, the more tapes can be reused, the less they strain the world’s energy sources. (Producing the broadcast-standard tapes used by television and cable operators might use as much as a gallon of petroleum.)

For the near term, at least, there’s much business to be done in recycling.

“I give it … maybe five years for a complete conversion in the industry (to DVD),” says Robert Gatica, Tropical Media’s operations manager. “Companies still use videotape for promotional things.”

Consumers, though, are making the switch in droves. DVD sales have skyrocketed in recent years, going from 688,000 units sold in 2003 to about 1 billion in 2004, according to Alexander & Associates, a New York-based analysis and consulting firm to the home entertainment industry. Meanwhile, consumer spending on VHS tapes reached a high of $20 billion in 1999 and dropped to less than $6.9 billion last year.

Los Angeles-based MSE Media Solutions recycles only professional-format videotape because individual VHS orders aren’t as economical for the company, chief engineer Bill King says. They might consider an order of several thousand VHS tapes, King says, “ship them off to Mexico, but even then, it’s going the way of the horse and buggy.”

A more consumer-friendly approach is taken by GreenDisk in Sammamish, Wash., and its outlets nationwide. For about $30, the company provides households and companies with “technotrash cans” to dispose of tapes, CDs, cell phones, cartridges and other modern-age techno-waste. When their cans are full, consumers can go online to schedule pickups. The company also offers a discard-by-mail version of the service.

David Beschen, GreenDisk president and founder, says his company takes in 10,000 to 20,000 VHS tapes a week and sees the number steadily rising. He contracts with small, nonprofit organizations to handle the degaussing.

King, of MSE Media Solutions, points out that such processes fall short of the true sense of the word “recycling,” of turning the products into something new. “It’s actually reconditioning. The tape shell is made from engineering resin that can’t be reused.”

Yet Sony Corp. announced in August that it’s found a way to do just that. The solid polystyrene cases are chemically modified to create a water-soluble liquid polymer that can then be used to pull pollutants from industrial wastewater.

A single cassette shell can treat 65 barrels of wastewater, according to the company’s Web site.

Keith Austin, the former president of video recycler Keith Austin Enterprises in Santa Barbara, Calif., predicts that “by 2010 we will be in a tapeless world. We’re going beyond the blue-laser DVD and, by 2008, there will be 100 gigabytes on one DVD.”

Beschen envisions a rosy future of another kind: new forms of recycling.

“I believe in what Buckminster Fuller said and did,” he says. “Invent something.”