At least 50 per cent of the blood is collected from professional donors. Most of the donors usually remain sick or are drug addicts, it was gathered.

It is often seen that they sell blood only to buy drugs with that money. They are seen sitting on the premises of blood banks.

The blood of professional donors contains inadequate blood cells and harmful virus like Hepatitis B and other germs, sources said.

At Rajshahi Medical College Hospital (RMCH) blood bank, at least 30 per cent of the collected blood is from professional donors, 50 per cent from relatives of patients and the rest from voluntary donors, said a study.

However, RMCH blood bank chief Assistant Professor Dr Mosaddek Hossain said that they collect and supply blood after tests under the Safe Blood Transfusion Programme. The tests include HIV, HBsAg, (Hepatitis B virus), HCV (Hepatitis C virus) and VDRL (test for syphilis).

In 2003, a total of 12,500 blood bags were collected in hospital in the city. Of those, HCV positive was found in 44 bags, HBsAg positive in 33 bags and VDRL positive in eight bags. However, no HIV positive was found.

Private blood banks do not have any screening facility, the sources said. Their owners admitted that they usually do not go for screening tests. They said screening tests cost about Tk 450 per bag and they have to give Tk 90 per bag of blood to professional donors.

" Screened blood should not be sold at below Tk 700 per bag, which most users can not afford," said an owner of a private blood bank. One bag of blood sells at around Tk 350 at private blood banks.

There are six private blood banks in the city, each selling about 200 bags every month.

Private blood bank authorities usually tell the users that the blood is screened and safe, some users said.