Every year, Americans toss out as much as 4.5 million tons of old mobile phones, laptops, televisions, Xboxes and other electronic gadgets.

Some is recycled; some is repaired and refurbished for reuse; and some is thrown into landfills or incinerators. Almost none of it, however, is "dumped" overseas.

That, at least, is the conclusion of the first comprehensive survey of what happens to U.S. e-waste after it is dropped into a recycling bin. Published in February, the study by the U.S. International Trade Commission surveyed 5,200 businesses involved in the e-waste industry (companies that received the survey were required by law to complete it, and to do so accurately), and found that almost 83 percent of what was put into American recycling bins in 2011 was repaired, dismantled or recycled domestically.

According to the same survey, only 0.13 percent of the 4.4 million tons of e-waste that Americans generated in 2011 was sent overseas for "final disposal" — a term that explicitly excludes recycling and reuse — with an additional 3 percent sent abroad for "unknown" purposes.

Reality is a far cry from the long-standing claim, first made by the Basel Action Network, a Seattle-based nongovernmental organization in 2002, that as much as 80 percent of U.S. e-waste is exported to the developing world. Amazingly, even with the wide currency the claim has enjoyed over the years among environmental organizations and the media, it was never based on a systematic study.

Misguided Efforts

This misunderstanding has led to several efforts at erecting partial export bans on U.S. electronics to developing countries, which — other studies demonstrate — import them as cheap and sustainable alternatives to new equipment. As a result, perfectly usable electronics are diverted into a recycling stream, where they are turned into raw materials, rather than into markets where they can be reused for years.

There are no statistics on how many used gadgets were exported from the U.S. to the developing world in 2002. Nor, for that matter, can anyone say for sure what happened to those gadgets. No doubt, many were broken down in developing-world facilities, where low-technology and often-hazardous methods of recycling and disposal were employed (such as the use of acids to strip copper and other metals from circuit boards in open, unprotected environments).

Anecdotally, I have been told by recyclers in southern China that cheap, secondhand electronics exported from the U.S. and, to a lesser extent, the European Union were used by Chinese computer labs, offices and dormitories in the 1990s through the mid-2000s, when new gadgetry simply wasn't affordable. (There has been no comprehensive survey to verify these claims, however.)

It was a good deal for the U.S., tooIn the 1990s and early 2000s, America didn't really have an electronics-recycling sector, and those machines would have been put in a landfill if China hadn't wanted them. Nonetheless, as China developed, and incomes rose, demand for those used machines dropped off.

The good news is that a similar cycle is occurring in Africa, where used electronics from the EU and the U.S. have become a critical means of bridging the global digital gap. Unlike Chinese imports in the 1990s and early 2000s, the African imports are being surveyed and quantified.

For example, a 2011 study by the United Nations Environment Program determined that only 9 percent of the used electronics imported by Nigeria — a country that is regularly depicted as a dumping ground for foreign e-waste — didn't work or were unrepairable, and thus bound for a recycler or a dump. The other 91 percent were reusable and bound for consumers who couldn't afford new products.

Nigerian Experience

That certainly doesn't excuse the hazardous means that some Nigerians use to recycle old electronics (and, increasingly, those old electronics are thrown away by middle-class Nigerians, rather than being imported from abroad). Yet it also doesn't suggest that the U.S., Europe or even China (a growing source of e-waste) are to blame, either.

So what happens to the 14 percent of U.S. e-waste that isn't processed domestically, sent for "final disposal" in other countries, or isn't otherwise unknown? According to the trade commission report, most is exported as recycled commodities to be reused by manufacturers in new products; as reusable gadgets; and even as warrantied products for repair.

Less than half of those exports, by weight, go to developing countries; the majority is shipped to member countries of the Organization for Economic Co-operation and Development, such as Japan and Belgium, where the recyclable material is handled better in factories than it can be in America.

The U.S. shipped almost three times as much e-waste to Belgium in 2011 as it did to sub-Saharan Africa, according to the trade commission.

Why? Belgium has one of the world's best (and cleanest) factories for the extraction of precious metals from circuit boards and other complicated devices. It is thus capable of paying far more for them than a recycler in Nigeria with little more than some jars of acid capable of refining gold, though not platinum and other precious metals.

The biggest story embedded in the trade commission's story isn't that U.S. e-waste exports are greener than ever. Rather it is that the domestic electronics-recycling industry has grown into a large, mature business that views export as a second choice, not the first one.

The industry generated sales of $20.6 billion in 2011, compared with less than $1 billion in 2002, according to figures from the trade commission as well as the Institute of Scrap Recycling Industries, an industry association.

Recycling Jobs

E-Stewards, a strict, U.S.-based electronics recycling certification standard that bans most exports, has grown from having zero member facilities certified in 2010 to 102 in 2013, including several belonging to Waste Management, North America's largest recycling company. Most of what these companies — certified or not — produce are commodity-grade raw materials, such as metals and plastics, usable for new products in the U.S. and abroad.

More revealing, yet, is the employment pictureThe institute estimates full-time jobs in the U.S. electronics- recycling industry grew to more than 45,000 in 2011 from 6,000 in 2002. Some of those employees, no doubt, are involved in packing used electronics for shipment around the world, including to places where unsafe, environmentally damaging means of disposal are still used.

Thanks to the International Trade Commission findings and other, smaller-scale studies, we now know that most secondhand electronics are reused and recycled in the U.S. The toxic tide that frightened Americans into stashing their old computers in closets turns out to be nothing more threatening than a trickle.

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Adam Minter is the Shanghai correspondent for the World View blog at Bloomberg and author of the forthcoming "Junkyard Planet." The opinions expressed are his own.