LONDON (AP) -- An influential British medical think tank is tackling the question of how far society should go to boost the number of organ and tissue donors, and is weighing a proposal to pay for body parts.

Nearly all countries are struggling to meet the growing demand for organs, with different approaches being tried worldwide. In Spain, authorities assume people are donors unless they specifically opt out, while in Israel, people who donate organs gain priority for themselves and their family if they need an organ in the future.

Beginning Tuesday, the Nuffield Council on Bioethics is asking the public for its views on how Britain should respond to the growing demand for organs, eggs, sperm and other human material in medical treatment and research.

Previous reports from the council have strongly influenced government health policies and have also been referred to by other countries.

"How far should we go in encouraging people to donate an organ?" asked Dame Marilyn Strathern, chair of the council's working group at a news briefing on Monday. "Offering payment or other incentives may encourage people to take risks or go against their beliefs in a way they would not have otherwise done."

The Nuffield Council is an independent group funded by the Nuffield Foundation, Britain's Medical Research Council and the Wellcome Trust.

Dr. Keith Rigg, a transplant surgeon at Nottingham University Hospital, said other ways of encouraging people to donate body parts - like offering them and their family priority to receive organs if they needed one in the future or having the donor's funeral costs covered would also be considered.

British law forbids people from being paid for any body part, though egg and sperm donors can be compensated up to 250 pounds (USD$382) for their time and expenses. Participants in medical trials can also be paid a fee in line with minimum wage.

"The majority view in the transplantation community is that payment is not the way forward," Rigg said. "But we need to encourage debate to see what people really do think."

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