NHS Greater Glasgow and Clyde has blamed “human error” for the leaking of data pertaining to 86 transgender patients.

The error occurred on Monday, when the Sandyford clinic – which provides gender and sexual health services in the Glasgow area – sent an open email chain to transgender patients, advertising a new service.

As the email chain was not sent via BCC – which is standard practice – the full list of email addresses of people receiving gender treatment at the clinic was visible to all participants.

A statement from NHS Greater Glasgow and Clyde said: “Yesterday 86 individuals were sent an e-mail with information on a forthcoming event.

“The member of staff sending this email made the unfortunate error of attaching all the email addresses of the patients in the one email.

“Patient confidentiality is of the highest priority and we are extremely concerned that this breach has occurred as a result of human error.

“On review of the e-mail addresses we can confirm that a number of the individuals’ names and dates of births are discernible from the email addresses.

“We have already made the Information Commissioner aware of this issue and have been guided by him.”

Dr Pauline McGough told the BBC: “We are urgently taking the appropriate steps to contact the individuals concerned and will apologise unreservedly to them for any distress this may have caused.

“We will investigate this issue fully and take appropriate steps to ensure this does not happen again, including urgently reaffirming to staff the vital importance of handling sensitive data with the utmost diligence to maintain patient confidentiality.”