Over half a million Australian blood donors could be subjected to email and phone scams after their details were leaked online.

The personal information of 550,000 Australians who filled out online applications to become blood donors were stolen and posted on another website.

Names, addresses, phone numbers and birthdays were available for over seven weeks – before being deleted from the site.

Blood Service CEO Shelly Park says answers to personal questions were also taken, but the information is considered low-risk.

The AFP has launched an investigation, while the Red Cross says donors’ information is once again secure.