Doctors and IT experts fear a government plan to sell patient health data to the medicinal industry could threaten people’s privacy rights.

The plan would make millions of blood and tissue samples available for research. Data will be made anonymous, but doctors fear companies will be able to find out the identities of the individuals anyway. 

“It’s potentially a huge problem that they want to commercialise the data,” Mads Koch Hansen, the head of medical association Lægeforeningen, told Jyllands-Posten newspaper. “One could fear that companies would be willing to pay considerable sums to, for example, be able to trace people who require medicine for the rest of their lives.”

His sentiment echoes concerns expressed by general practitioners earlier this year.

Last year, the National Biobank of Denmark was established as part of national lab Statens Serum Institute (SSI) and over time it is expected to contain 15 million biological samples.

The biological samples, which are linked to information including CPR numbers, medicine use and illnesses, gives researchers new opportunities to track illnesses from an early stage.

“A health registry of this size will definitely threaten Danes’ privacy,” Thomas Ploug, a professor at Aalborg University and a member of Det Etiske Råd, a panel that advises parliament on ethics issues, told Jyllands-Posten. “The registry contains an immense amount of sensitive personal information which can be abused in a number of ways.”

Niels Elgaard Larsen, the head of IT-Politisk Forening, a computer policy group, also warned of the danger.

“We're fooling ourselves that it is possible to make all sensitive personal information anonymous,” Larsen said. “If you know a person was 192cm, what town he lived in and what they were treated for, you’d probably have enough information to identify the person,” 

But the registry has its proponents and Mads Melbye, the section head at SSI, rejects any grounds for concern.

“A sensible co-operation with the private sector is required if we are to discover new treatment avenues,” Melbye said. “But the identity of the individual will never be an issue.”

The health minister, Astrid Krag (Socialistisk Folkeparti), argued that the registry was about improving research and treatment, not selling information to the medical industry.