FOOLS or heroes? Edmond Wong Kai-man and Rita Tang Chi-kwan encountered both labels when they decided to donate their bone marrow to cancer patients. Their mothers were particularly fierce opponents, fearing they would suffer. Yet it is a simple and relatively painless procedure, say the pair, and the rewards of saving or prolonging a life make it worthwhile. Mr Wong, 27, was Hong Kong's first non-related donor, giving his bone marrow in secret in April last year. ''As soon as the hospital contacted me, I made the decision to have this operation,'' he said. His family was apprehensive but it was the recipient, a 21-year-old leukaemia victim, that he considered. ''Some people felt it was a foolish thing for me to do, but others treated me like a hero,'' he said. But the real hero in his eyes is Ms Tang. While he had some background knowledge through his job as a hospital lab technician, Ms Tang, a bank teller in her thirties, had never been in hospital. They first learned about transplants through an appeal to help Chinese-Canadian toddler Gordon Wu two years ago. They were among the thousands who offered to donate blood in the hope of matching his bone marrow type. No match was found, but the samples were kept on file. Ms Tang was contacted in March when a three-year-old leukaemia victim matched her bone marrow. ''My mother thought it would be dangerous, but the doctors talked to her and finally she agreed,'' she said. ''My family and friends thought it would be painful, but it's not too bad. It's like playing a couple of hours of badminton when you have not played for a while. Your body feels tired.'' The bone marrow is removed from the back under general anaesthetic. Donors spend a few days in hospital. Both were soon back to normal, but their good health did not extend to the patients. The boy is doing well but Mr Wong's recipient lived only six months. But he said: ''That was six months longer than he or she might have lived.'' And, like Ms Tang, he is prepared to donate again. ''I knew the operation would be safe and I felt really happy about doing it because I wanted to help someone,'' he said.