Thanks to Moore's Law, between 1997 and 2004 315 million computers in the United States alone will become obsolete, destined for a landfill or to be disposed in some fashion or other. What few people think about when they hear this figure is that a typical computer (and of course, all electronic equipment in general) contains thousands of separate components, many of which are made of materials that can be highly toxic, such as some plastics, plastic additives, and heavy metals. All of this waste, from 315 million obsolete computers, will, sooner or later, probably produce an environmental pollution nightmare that will haunt many generations to come. A whole term has been recently coined for computer and electronics-related pollution: E-Waste.

Typical E-Waste Hazards

By far one of the most distressing of the toxic waste hazards associated with computers and electronic equipment is lead. It has been noted that over 40% of all the lead in a typical landfill comes from consumer electronics, as it is widely used for solder, printed circuit boards, and glass panels and shielding for computer monitors. A typical computer has about 6.3% of its weight in lead, so between 1997 and 2004 almost 1.2 billion pounds of lead will have come from junked computers. Unless something is done to provide more efficient recycling of this lead than currently exist or some other means of more environmentally-friendly waste disposal is found, nearly all of this lead will find its way into the environment, and cause serious pollution.

Cadmium is yet another heavy metal that can be commonly found in electronic equipment. It is, like most heavy metals, also toxic and is known to cause permanent damage to human kidneys when its compounds are inhaled or ingested, and seems to have other long-lasting evil environmental effects that are still under research. It is most often used in surface mount chip resistors, in the preparation of certain types of solid-state devices, and in infrared sensors, in modern electronics. It is also sometimes used as a treatment for plastics. All in all, it actually does make up a fairly small fraction of the contents of a typical computer, however, with the estimate of 315 million computers getting junked in the near future, it still means that over 2 million pounds of this heavy metal will potentially cause severe pollution in the coming years.

Found in some types of solder, electronic relays (found most commonly in a computer within power supplies), and some types of sensors, mercury is another heavy metal that is a cause for concern. It is known to cause brain damage and persists in the environment. Because of recent initiatives that have served to reduce the use of mercury in consumer electronics, it makes up a negligible portion of any given modern computer's components, but with 315 million computers, that still means over 400,000 pounds of mercury that could potentially cause environmental harm.

Hexavalent Chromium, made recently famous by the movie Erin Brockovich, is still sometimes used in the manufacture of computer casings as an anticorrosive and as a steel hardener. An estimated 1.2 million pounds of these toxic chemicals can be found in the 315 million odd computers that are destined to become scrap in the near future.

Plastics of various types would make up the bulk of computer waste, over 4 billion pounds of it from the 315 million computers that will become junk by 2004. Some of this plastic is efficiently recyclable, but some other types, especially polyvinyl chloride or PVC, are troublesome buggers that are not only toxic (see the PVC node for details) but also complicate the recycling process for other plastics. You wouldn't want to put PVC in an incinerator, as this would produce large quantities of dioxins and other carcinogenic substances. This presents a serious problem as over a quarter of all the plastic used by the electronics and computer industry is PVC. 1 billion pounds of PVC by 2004. Way to go, bub.

Brominated flame retardants are also widely used in the computer and electronics industries, as treatments for printed circuit boards and for plastics used for housings for monitors and computer casings. Although its precise effects on the human body are as yet undetermined, current research findings have shown that it produces neurotoxic effects similar to PCB's and other (now banned) pesticides. Their presence also makes the recycling of plastics treated by them problematic and hazardous for those involved, as it converts to more dioxins, furans, and other hazardous chemicals. Over 350 million pounds of this toxic chemical will be present in the 315 million monitors that get junked along with their computers by 2004. Their presence in circuit boards and other components could easily double this figure.

Possible (non)-solutions

Incinerating computer waste is something you probably shouldn't even think about. The high quantities of PVC in a typical computer, along with copper, are the perfect recipe for the creation of large quantities of cancer-causing dioxins. The incineration of plastics that have been treated with brominated flame retardants at low temperatures also produces particularly nasty types of dioxins and furans. Attempting to smelt steel computer casings that have been treated with hexavalent chromium releases that toxic chemical into the atmosphere.

It is common knowledge that even the best sanitary landfills can leak and a certain amount of chemical and metal waste gets out. The situation is far worse for older or less stringent dumpsites. The relays inside old computers' power supplies will eventually release their mercury, and brominated flame retardants present in some computer plastic also get released. Leaded glass, such as is used for some computer monitors winds up leaching lead in the presence of acidic water such as is common in landfills.

Recycling of old computers could be one way to ameliorate some of these problems, but current methods of recycling are quite inefficient and worse, some just wind up shifting the environmental hazards to other by-products that cause their own sets of problems. Recycling of computer junk is also a fairly rare occurrence: only 6% of all computers rendered obsolete in 1998 actually were recycled. As previously noted, the large quantities of PVC and brominated fire retardant compounds make recycling problematic and dangerous, which is why most plastic recycling services refuse to process any plastic e-waste at all. Present methods for the recycling of heavy metals such as lead and cadmium also don't significantly reduce the pollution associated with these substances. So, recycling is at most a stop-gap that may serve to reduce some of the evil effects of e-waste.

Waste exports to third world countries are a highly controversial "solution" to this problem. It of course, is not a solution at all, as environmental pollution is a truly global problem, and this will only serve to delay the inevitable. It may actually make future environmental pollution problems far worse, as these third world countries are ill-equipped and monetarily strapped to effectively deal with this problem, and they could do things with this waste that would make things very bad for them in the beginning, but affect the entire world for many generations to come. But heck, the industrialized world has rarely been known for taking the long view in matters such as this... There have been treaties such as the Basel Agreement in 1994 that have prohibited this dumping of toxic waste to third-world countries by 1998, but of course the United States has refused to be a part of it and has lobbied for bilateral trade agreements with countries such as China and Taiwan who are not signatories to receive their waste computer equipment.

A highly graphic portrayal of what these waste exports do to the Third World can be found in this BBC News photo essay:

A Real Solution, or part of it anyhow

Recycling and reuse can only go so far in attempting to ease the e-waste nightmare. The only really serious steps that can be taken at this point that would actually help would be a commitment from the producers of these computers and electronic devices to phase out their use of toxic substances in their manufacturing processes, and to take responsibility for disposing of all of the devices they produce. The European Union is attempting to create directives that would require that all manufacturers of electronic goods take responsibility for disposing their broken equipment, and to totally phase out the use of lead, cadmium, bromide-containing flame retardants, and PVC. The thinking here is that the cost to these corporations of disposing their waste will encourage them to use less toxic and easier to dispose of materials. The United States, however, has raised strong objections to these moves to ban the use of hazardous chemicals and to require companies to take responsibility for disposing of the waste materials in their products.

An end to Moore's Law and the generation of waste that it causes would also help to ease the problems somewhat. If computers and electronics did not become obsolete as rapidly as they do, it would keep e-waste down as it would take longer for computers to end up in the scrap heap. This would also give more time for scientists and engineers to find ways of making computers that are safer for the environment.


"Just Say No to E-Waste", Silicon Valley Toxics Coalition,

"Life After Death", Scott McMurray,,1640,8772,00.html

Carnegie Mellon Green Design Initiative: Computer Recycling Page: