Computers have come to symbolise a shiny, hi-tech, post-industrial world, yet behind the screens there's still the whiff of old technology about them. Your average hard drive contains all sorts of hazardous substances, such as cadmium and lead, while monitors house flame retardants that are set to be banned in Europe next year. One study, at the UN University in Tokyo, calculated that making a PC uses up to 10 times its weight in fossil fuels.
Computer disposal is a huge problem, too. Thanks to software companies constantly upgrading their products, the pressure is on users to ditch old hardware and modernise. The result is a lot of computers finding their way to landfill - the UK alone dumps 2m working PCs each year, according to Wastewatch.
Two EU directives, due to become British legislation next year, should make the buying and disposal of computers easier for green consumers. The first, in January 2006, is known as Weee (Waste from Electrical and Electronic Equipment). This obliges electronics firms to offer take-back schemes, and is likely to mean them funding waste sites where computers, fridges, televisions and the like can legally be dumped for recycling.
Some computer makers already take back their products. Sun Microsystems (01252 420000; uk.sun.com), which was the best buy in Ethical Consumer magazine (0161-226 2929, ethicalconsumer.org), claims to put 80% of returned hardware back into circulation. Dell (0870 152 4699; dell.co.uk) promises to recycle its computers, and will take in other brands if you buy one of its PCs.
Many independent companies specialise in recycling PCs, but you don't always know where your computer is going to end up. Is it being shipped to the developing world where toxic components are "recycled" by poorly paid people with little regard for health and safety?
Another problem is that many recycling schemes are geared solely to businesses. That's fine if you are a company with a lot of hardware to offload - you could donate it to schools and community groups through Computer Aid (020-7281 0091, computeraid.org). But it's not so good if you are an individual - you'll probably pay. For a recycling scheme near you, contact the Industry Council for Electronic Equipment Recycling (020-7729 4766; icer.org.uk).
A second EU directive arrives in August next year. The RoHS (Restriction of Hazardous Substances) directive is effectively a ban on substances thought to be harmful to health and the environment, and puts the onus on manufacturers to find safer alternatives. From that time, new computers should, theoretically, be free of dangerous heavy metals and certain brominated flame retardants.
Most of the big companies are moving towards this end: some, including Samsung (0870 242 0303, samsung.co.uk) and Sony (08705 111999, sony.co.uk), have promised to phase out other potentially harmful substances not on the RoHS list.
Several eco labelling schemes exist for computers, which set minimum standards of environmental and ethical performance. The most relevant - in that you might be able to buy labelled equipment in this country - is Germany's Blue Angel (blauer-engel.de). There is, however, only a smattering of products on the site.
Or forget the new computer, and buy secondhand or upgrade an existing model (try Environ, 0116-222 0232, environ.org.uk). While this might mean you can't play the latest games or run the newest software, you may save money - and do a tiny bit for the environment, too.
· Avoid chunky cathode ray tube monitors; plump for LCD flat screens instead. These contain less harmful substances and use less electricity
· Switch off computers when not using them: it'll cut your electricity bills (by up to £250 a year for a two-PC household) and help the environment
· If you're disposing of old equipment, it might be worth waiting until January 2006, when new legislation should make it easier