At least 65 non-specialist doctors have been appointed as consultants in Irish hospitals in recent years.
Solicitors are warning that giving jobs to people that do not have the necessary qualifications could have serious legal consequences.
The practice could leave the HSE legally exposed in the event of an injury to a patient.
According to The Sunday Business Post, these non-specialist consultants include 12 psychiatrists, 10 surgeons, seven anaesthetists and six obstetricians.
The HSE's director of human resources has reportedly advised hospitals to put plans in place to deal with any problems that could arise.
Sinn Féin spokesperson on health Louise O'Reilly - who obtained the new figures from the HSE - said the executive's approach to dealing with the issue has not been good enough:
"There are patients who will be going in to see these consultants tomorrow morning," she said.
"The patients themselves I suppose will be worried.
"The HSE has said that this does pose a risk so they are aware that there is a problem - and yet it was only when this issue was highlighted in the media that we actually saw some action from the HSE in this regard."
Earlier this year the Irish Hospital Consultant Association (IHCA) warned that the practice of appointing under-qualified doctors to highly-skilled consultant positions “violates the most basic professional standards within the public health services.”
The association believes the number of non-specialists appointed to consultant posts may actually be higher than feared – as the HSE does not centrally collate the details of doctors recruited on agency contracts.
The association urged the HSE to put an end to the practice immediately.
The Royal College of Physicians of Ireland has again warned that the country is experiencing a “major and persistent crisis in the recruitment and retention of medical staff.”
It said that unless the government takes radical action, the consequences for the health service will be severe.
It comes after the Irish Nurses and Midwives Association (INMO) warned that a record number of patients were forced to wait on trolleys or in wards in Irish hospitals in the first half of 2017.
INMO general secretary Liam Doran said the crisis will not be solved until the recruitment and retention difficulties in the health service are addressed.
