In Guiyu, southern China, residents tell stories of Chinese tea made with local water that turns a dense black instead of glowing amber. The town's water has become practically undrinkable and most people living in Guiyu now only drink the water routinely trucked in from neighbouring towns. Environmental groups have long blamed groundwater pollution for the situation, but the source of the contamination has remained elusive. However, Zeina Alhajj, a campaigner against toxic waste for Greenpeace International, says the pollution is likely to be connected to the town's main industry: recycling electrical goods.

Over the past 10 years, Guiyu, situated northeast of Hong Kong, has transformed from a poor rural rice-growing community into China's centre for processing and recycling used electrical goods. Men, women, and children from the town dismantle old computers, televisions, mobile phones, and other electronic waste items (e-waste) to extract valuable metals. Workers strip wires for the copper they contain, melt lead solder from circuit boards, and use acid baths to separate precious metals. Those employed to do this work often use their bare hands to dismantle electrical objects and wear little or no protective clothing. A fluctuating migrant workforce makes it difficult to estimate the numbers employed in the trade but Chinese and western press accounts put the figure at 50 000–100 000 people.

In Nov, 2003, a report by researchers at the Medical College, Shantou University, China, found that people employed in the incineration of circuit boards and cleaning of plastics from used electrical goods in Guiyu had a high incidence of skin damage, headaches, vertigo, nausea, chronic gastritis, and gastric ulcers.

3 years ago a report-the first major exposé on the industry-from the environmental watchdog Basel Action Network and the Silicon Valley Toxics Coalition found high concentrations of lead in environmental samples from sites in and around e-waste recycling facilities in Guiyu, New Delhi in India, and Karachi, Pakistan. In one water sample taken from the Lianjiiang River in Guiyu the group found concentrations of lead that were 190 times higher than recommended in WHO's drinking water guidelines. From maintenance stickers and telephone numbers on the waste, the investigation team identified its source: North America, Japan, South Korea, and Europe.

Greenpeace International uncovered similar findings in March this year. The organisation sent scientists to Guiyu and e-waste recycling sites in the Mayapuri and Buradi districts of New Delhi to assess workplace and environmental contamination. Visiting industrial units and dumpsites, the team collected 70 environmental samples including indoor dust, river sediments, and groundwater for analysis back at the Greenpeace Science Unit. The results, released in a report on Aug 17, reveal high concentrations of heavy metals used in electronics, including lead, tin, copper, cadmium, and mercury, in the samples. Researchers also detected polybrominated biphenyl ethers, a type of flame retardant, and polychlorinated biphenyls (PCBs), which are used in insulating fluids.

Arnold Schecter, professor of Environmental Sciences at the University of Texas School of Public Health, USA, says: “If dioxins, PCBs, and brominated flame retardants are elevated in a person's body there is the possibility of excess cancer, immune deficiency, and reproductive or developmental pathology, assuming the levels are high enough and the person genetically sensitive to these chemicals. PCBs and brominated flame retardants would probably be present.” But, he adds, while environmental monitoring data can indicate potential exposure, only blood concentrations of these chemicals can reveal actual exposure.

David Santillo a researcher from the Greenpeace Science Unit, University of Exeter, UK, and one of the authors of the Greenpeace study, admits the findings only illustrate the potential health problems but he believes that they should act as a springboard for scientific studies into the health and environmental side-effects of the industry. “It's quite shocking that, until now, an industry that has developed over the last two to three decades has never been investigated scientifically beyond people visiting recycling sites to take photos and interview workers”, he says.

In developed countries, e-waste recycling takes part in purpose built plants under controlled conditions. But because the process is costly many developed countries export their e-waste to developing countries where labour costs are cheap and occupational and environmental standards lax or non-existent.

Ted Smith, chair of the Computer Takeback Campaign, says e-waste is difficult to recycle in an environmentally safe manner. “In the US, it's cheaper to ship it than process it domestically, so the pollution runs downhill from rich to poor countries”, he explains.

India, Pakistan, Nigeria, as well as China, have now become prime destinations for the west's toxic waste. For countries that have signed up to the 1989 Basel Convention on the Control of Transboundary Movements of Hazardous Wastes and their Disposal-an international treaty under the auspices of the UN Environment Programme (UNEP) restricting the shipment of hazardous waste from richer to poorer countries-the process is illegal. For others, such as the US, which is the only developed country not to have ratified the Basel Convention, this type of export remains within the law.

And, unfortunately, the problem looks set to get worse. The UNEP estimates that every year 20 to 50 million tonnes of electrical waste is generated worldwide; China alone throws away 4 million PCs annually. “Because people rapidly replace computers with the latest technology, obsolete computers have been accumulating. It's this rapid obsolescence that has led to a glut of machines”, says Smith.

Some countries are taking action to stem the amount of hazardous waste they produce. To make recycling safer, the EU has banned the use of certain hazardous substances in new electrical and electronic products put on the market from July 1, 2006. The EU, Japan, South Korea, Taiwan, and several US states have also introduced legislation making producers financially responsible for the disposal of their end-of-life products. By doing this, governments hope to slow the technological innovation and intense marketing that pushes consumers to rapidly replace electronic items and instead encourage companies to make products with longer lifespans that are easier, safer, and cheaper to recycle.

Although regulatory efforts are addressing the problem in some countries, in many parts of Asia, the sector remains largely lawless and its impact on the environment and on the health of recycling workers poorly studied.

In 2000, the Chinese government, responding to pressure from environmental groups and the media, banned the import of electronic waste into the country. But the trade continues because, according to Greenpeace's Alhajj, the legislation is weak and the ban has been difficult to enforce.

While some see stricter controls at the points of export and import as key, Greenpeace says the real problem is the hundreds of toxic chemicals that go into electronic goods. Santillo believes companies should manufacture products using safe, non-hazardous materials. “As long as toxic materials go into electrical products there are always going to be problems at the end of the product's life”, he says.

Many environmental groups see commitment from the US-the biggest producer of e-waste-as crucial to progress. Congress has not been in favour of producer responsibility because some computer manufacturers prefer a consumer fee, where money for recycling is added onto the product's price. “Some companies, like IBM, take an ‘everyone else but them should pay’ attitude”, says Smith.

But while environmental campaigners like Smith continue to push for legislation, researchers could also be doing more. Schecter believes it is important for those in the field to work with environmental groups, speak to the press, and contact elected officials. “There is a fear on the part of most scientists in communicating in anything other than scientific journal or conference format, or to get involved in policy matters”, he says.

Whatever the plan, something needs to be done to protect workers, as most are in not in a position to bargain about their working conditions. Alhajj, who visited e-waste recycling sites in New Delhi and spoke to workers, says: “Some feel that if they are not dropping immediately there's nothing to worry about. Others know there maybe risks involved but to them employment is more important.”