Organ transplant tourism is growing in developing countries, and new guidelines are needed to track the trend, the World Health Organization said Friday.

The UN agency is concerned about increasing cases of commercial exploitation of human materials such as organs for transplant.

"Human organs are not spare parts," said Dr. Howard Zucker, WHO's assistant director general of health technology and pharmaceuticals. "No one can put a price on an organ which is going to save someone's life."

The agency held a meeting of international experts this week on transplantation, including "transplant tourism." Wealthy Westerners who may urgently need a kidney, for example, may  buy one from someone in a developing country who is persuaded to sell the body part since someone can live with only one kidney.

"We believe five to 10 per cent of all kidneys transplanted were in 2005 transplanted in this setting," said Luc Noel, the head of WHO's unit, told a news conference at the agency's headquarters in Geneva.

In Pakistan, from 40 per cent to half of residents in some villages have only one kidney each because their other was sold to a wealthy person, likely from another country, said Dr. Farhat Moazam of the Sindh Institute of Urology and Transplantation in Karachi, Pakistan, and one of the participants at the meeting.

People from North America, the Middle East and Europe may also head to Egypt and the Philippines for organs. 

Donors may be offered $2,500 US for a kidney but may receive only half because of the broker's cut.

"Commercialized organ transplantation ensures the middlemen become rich, the sick get bad treatment and the poor suffer the consequences," said Jeremy Chapman, of the renal unit of Westmead Hospital in Sydney, Australia.

Advances in transplantation surgery have also increased demand for livers, hearts, corneas and bone marrow, while the waiting list for organs from cadavers is long.

Many people who sell their organs and tissue do not receive proper followup care, which increases the health risks, Noel said.

To improve transparency, WHO will set up a global forum to develop new guidelines that include ethical principles for donation and transplants.

With files from the Associated Press