Shortage spawns tall tales of abductions, forced surgeries.(Knight Ridder Newspapers)

Poor children on the streets of Brazil and Mexico being kidnapped for their organs. Women in Argentina waking up in hospital beds with mysterious small incisions that indicate a surgeon has secretly removed a kidney.

These stories reverberate around the Internet, tabloid newspapers and some TV shows. Similar tales are told in India and Turkey and around the world.

Many journalists, however, have tried to find solid proof of these cases without success.

There is plenty of evidence of a thriving black market for organs. Men and women in Moldova, Iran, India and the Philippines are eager to provide a kidney for as little as $1,000.

But there is no proof whatsoever of the more outlandish stories of kidnappings and forced operations, says Nancy Scheper-Hughes, a professor of anthropology at the University of California at Berkeley and the head of Organs Watch, which keeps track of the worldwide black market.

Scheper-Hughes says Iran has legalized the practice of selling kidneys and the Philippines is thinking of doing so.

The most common story she has heard in Latin America is about servants of wealthy people _ gardeners and maids and such _ being coerced into donating a kidney to their ...