Most people assume that their trash ends up in a landfill somewhere far away (if they think about this at all). But growing concern over the environmental impact of waste—discarded electronics, in particular—has prompted a team of researchers at the Massachusetts Institute of Technology (M.I.T.) to take a high-tech approach to studying exactly what people are tossing out and where those items are ending up.

The researchers, part of M.I.T.'s Senseable City Lab, have developed electronic tags that they're hoping as many as 3,000 volunteers in Seattle and New York City will affix to different items they throw away this summer as part of the Trash Track program. These tags will contact cell phone towers they pass as they flow through the trash stream to their final destinations, helping the researchers monitor the patterns and costs of urban disposal.

The tags are battery-powered microprocessors with the ability to send out cell phone signals, says Assaf Biderman, associate director of Senseable City Lab. The lab's computer servers will track these signals as they are picked up by cell phone towers (each of which has an address), using the strength of the signal to determine the tag's distance from each tower and triangulate the approximate position of the trash.

Although some signals might be blocked as a result of tagged items being hauled or stored in steel or aluminum—conducting materials that block electrical fields—Biderman says the tags will resume functioning once the items are moved someplace more open. If the items don't move, then the lab's trash trackers will mark the spot where they lost the signal as the final resting place.

Of particular interest to the researchers are electronic waste (including computers, monitors and iPods) and plastics (which exist in a variety of forms, many of which are recyclable), not to mention all-time enemies of the environment such as Styrofoam and tires. "Some of these things are interesting to tag because of their impact on the environment, others because of their volume in relation to overall domestic waste," Biderman says. The best way to improve the sanitation system, he adds, is to look at how it functions and how objects move through its garbage trucks, trash barges, incinerators and landfills, among other components.

The researchers will present the results of their study at events held on September 17 at both the Seattle Public Library and the Architectural League in New York City. Each location will also feature an Internet-based presentation that lets attendees see tagged trash moving in real time. Trash Track is just one example of "Internet of things," Biderman says, which is "what happens when every object is addressable."