"The global materials flow of electronic and electrical equipment requires a global approach," explained Ruediger Kuehr, executive secretary of the UN project, called Solving the E-Waste Problem (StEP).

Lead in cathode ray tube and solder Arsenic in older cathode ray tubes Selenium in circuit boards as power supply rectifier Polybrominated flame retardants in plastic casings, cables and circuit boards Antimony trioxide as flame retardant Cadmium in circuit boards and semiconductors Chromium in steel as corrosion protection Cobalt in steel for structure and magnetism Mercury in switches and housing

He said growth in the consumption of goods and devices around the world meant the problem would only get worse if left unchecked.

"Just look at places such as China and India; in all of these transitional countries, the demand for electrical and electronic devices is exploding," Mr Kuehr observed.

The decreasing cost of replacing computers, mobile phones and other gadgets, and the speed with which technology goes out date, has resulted in more and more devices ending up on the scrap-heap. The European Environment Agency has calculated that the volume of e-waste is rising about three times faster than any other form of municipal waste. If not disposed of properly, e-waste can result in toxic substances seeping in soil and groundwater, harming the local environment and people's health.

'Informal' recycling

Klaus Hieronymi, business environment manager for HP, said the initiative would address the environmental and health concerns. The main problems were in developing nations in Asia, Africa and South America, where "informal" recycling networks operated, he added.

"Basically, people are going round collecting PCs, printers and fridges, and take them home into their backyard.

"They earn money by dismantling the products, salvaging parts, and removing precious metals."

But they lacked proper skills and equipment, leaving themselves and the local environment exposed to harmful substances, he warned.

"For example," Mr Hieronymi explained, "burning salvaged cables to expose copper wires, rather than using machines to cut away the casing, results in toxic fumes being emitted."

Mr Ruediger said that a team of Swiss researchers, who were part of the StEP partnership, were providing training for the recyclers.

"It is in order to make people aware of what they are doing and the impact on their environment and on their health."

Raising awareness

In industrialised nations and established markets, the initiative will focus on making consumers aware of the consequences of throwing away equipment that still works. Taskforces will help shape government policies and look at concerns surrounding products' design, life expectancy and recyclability. And the UN initiative will build on the framework set up under the EU's Waste Electrical and Electronic Equipment (WEEE) Directive. The directive requires producers to bear the cost of the collection, recovery and disposal of devices no longer wanted by consumers.

"It will challenge companies to improve the design and performance of their goods," Mr Ruediger predicted.

As well as involving leading manufacturers of electronic goods, the taskforces will also include academics, government officials and NGOs. The long-term goal of the initiative is to develop a global standard for recycling, and improve the collection and recycling of e-waste. StEP's secretariat will be hosted by the United Nations University in Bonn, Germany.

Mounir's family are zabaleen (rubbish collectors) living where life's left-overs in the great metropolis of Cairo end up. Here the detritus from many of Cairo's 16 million inhabitants is carefully sorted, compressed, washed, resold, reworked, or simply used again.

The arrival of the zabaleen about 50 years later from villages in Upper Egypt pushed the wahiya up a notch. Now the wahiya are middlemen, acquiring the rights to service buildings and selling collection routes to the zabaleen.

Zabaleen make money from feeding the organic waste (about two-thirds of the total) to their livestock and recycling the rest.

The women of the household sort out the various categories - plastics, glass, metal, paper and textiles. It's hard work - but more environmentally friendly than the mechanised garbage crushing trucks from Europe that the municipality brought in about 10 years ago. Once rubbish has been mechanically compressed, no recycling is possible. It can only be dumped.

Invisible industry

Mounir's wife Layla empties bags on the floor for her four daughters to rummage through. She sees her job as vital for the city's survival.

"We don't like attention. Rubbish is never attractive and we're quite happy carrying on quietly... but our work supports a whole industry that's virtually invisible to most people."