San Jose, Calif. ? What happened to that old computer after you sold it to a secondhand parts dealer?

Environmental groups say there’s a good chance it ended up in a Third World dump, where thousands of laborers burn, smash and pick apart electronic waste to scavenge for the precious metals inside unwittingly exposing themselves and their surroundings to innumerable toxic hazards.

A report being released today documents one such “cyber-age nightmare” a cluster of villages in southeastern China where computers still bearing the labels of their former owners in America are ripped apart and discarded along rivers and fields.

The authors of the report, called “Exporting Harm: The High-Tech Trashing of Asia,” hope it puts pressure on U.S. companies and lawmakers to increase domestic recycling efforts.

Investigators who visited the waste sites in Guiyu, China, in December saw men, women and children pulling wires from computers and burning them, fouling the air with carcinogenic smoke.

Other laborers, making $1.50 a day and working with little or no protection, burned plastics and circuit boards or poured acid on electronic parts to extract silver and gold. Some smashed lead-impregnated cathode ray tubes from computer monitors, the report said.

Consequently, the ground water is so polluted that drinking water has to be trucked in, the report said.

“I’ve seen a lot of dirty operations in Third World countries, but what was shocking was seeing all this post-consumer waste,” said one of the report’s authors, Jim Puckett of the Seattle-based Basel Action Network. “This is all stuff from you and me.”

A 1989 treaty known as the Basel Convention restricts such exports of hazardous materials, but the United States has not ratified it.

Computer waste in particular is becoming a difficult problem, with millions of devices becoming obsolete each year.

With no organized system of electronics recycling such as Japan and some European countries have, much of the nation’s e-waste is passed along a difficult-to-track chain of resellers and parts brokers, said Ted Smith, head of the Silicon Valley Toxics Coalition, which also prepared the new report.

The report says some in the industry estimate that as much as 50 percent to 80 percent of U.S. electronic waste collected in the name of recycling actually is shipped out of the country.