Each year, between 20 and 50 million tons of electronic waste is generated globally. Most of it winds up in the developing world.
Some of the most popular destinations for dumping computer hardware include China, India, and Nigeria. It can be 10 times cheaper for a "recycler" to ship waste to China than to dispose of it properly at home. With the market for e-waste expected to top $11 billion by 2009, it's lucrative to dump on the developing world.
Computers are much more than just wires and plastic; they are also a source of highly valuable metals, including gold, copper, and aluminum. One ton of computer scrap contains more gold than 17 tons of gold ore. Circuit boards can be 40 times richer in copper than typical copper ore. For this reason, workers in e-waste dumps in the southern Chinese city of Guiyu carefully sort the computers' hardware and melt down the most valuable parts.
Lead, mercury, and cadmium are a computer's most common toxic substances. When melted down, the machines release even more toxins into the air, ground, and water.
Although developing countries occasionally attempt to ban e-waste, the shipments can be vital to local economies. Some disposal sites employ more than 100,000 people. In Guiyu, the average worker can earn between $2 and $4 a day for disassembling what was once someone else's computer.
