How green is your computer   

Disposing of computers, monitors, printers and mobile phones is a large and growing environmental problem. Some 20m-50m tonnes of “e-waste” is produced each year. According to the European Union, e-waste is now the fastest-growing category. Last month new rules came into force in both Europe and California to oblige the industry to take responsibility for it. In Europe the Restriction of Hazardous Substances (RoHS) directive limits the use of many toxic materials in new electronic products sold in the European Union. In California mobile-phone retailers must now take back and recycle old phones.

Many technology firms are already eliminating certain chemicals and offering recycling schemes to help their customers dispose of obsolete equipment. Yet there is a wide variation in just how green different companies are, according to Greenpeace, an environmental lobby group that launches a new e-waste campaign on August 25th. It has ranked the top mobile-phone and PC-makers based on their progress in eliminating chemicals and in taking back and recycling products.

The RoHS rules ban products containing any more than trace amounts of lead, mercury, cadmium and other hazardous substances, including some nasty materials called brominated flame-retardants (BFRs). To do well in Greenpeace's rankings, firms must make sure both products and production processes are free of polyvinyl chloride (PVC) and some BFRs that are not on the RoHS list. Greenpeace also wants companies to adopt a “precautionary principle” and avoid chemicals if their environmental impact is uncertain.

Although not everyone will agree with Greenpeace's methodology, its ranking still has some merit. Nokia does well: the world's biggest handset-maker has already got rid of PVC from its products and will eliminate all BFRs from next year. But, Greenpeace grumbles, it is not sufficiently “precautionary” in other areas. Dell, however, scores well in this regard and on recycling, but loses marks for not having phased out PVC and BFRs yet, though it has set a deadline for doing so.