The Irish Examiner can reveal that the man, who made protected disclosures about health and safety management of hazardous chemicals at Casement Aerodrome, Baldonnel, has been summoned to appear before a Defence Forces medical board in August.

A brief report, issued prior to the board meeting, has accused the member of “chronic ineffectivity” due to anxiety and a “work-related industrial dispute”.

The Protected Disclosures Act was introduced in 2014 to protect whistleblowers from being penalised for reporting issues in their workplace.

This newspaper can also reveal that the man previously met with junior defence minister Paul Kehoe in Government Buildings, to discuss his concerns.

The man told Mr Kehoe that an Air Corps official ordered the shredding of health and safety inspection reports dating back to the 1990s. He is the second whistleblower to make such an allegation.

The claim was also made in a written disclosure submitted by a different whistleblower, in April — a statement that further named the official alleged to have ordered the reports’ destruction.

However, Mr Kehoe has ruled out any investigation into the documents’ disappearance, despite previously admitting that he could only offer “speculative” reasons as to why they cannot be found.

Six former Air Corps staff are suing the State, claiming their chronic illnesses are as a result of their exposure to toxic chemicals used in the course of their duties.

Opposition TDs say they have seen copies of the 1990s inspection reports, and the reports are said to show that it was long-known that the conditions at Casement Aerodrome were not up to standard.

This has prompted claims that the Defence Forces’ copies of the documents were deliberately destroyed to cover up knowledge of workers’ exposure to harmful substances.

Sinn Fein defence spokesman Aengus O’Snodaigh described the development as a “cause for concern”.

“I have written to the minister to raise my concerns and I will also be questioning Minister Keogh on this matter, in the Dáil, next week,” he said.

“It is a sad day when somebody raising concerns about the health-and-safety issues in the Air Corps is targeted in this way.

“It points to a worrying culture of cover-up and, instead of targeting the messenger, the military authorities would be better-served if they focused their efforts on addressing the major shortfalls in safety standards at Casement Aerodrome.

“I immediately call on the minister, and the military authorities, to stop the dismissal process and start addressing the very serious health and safety issues which have been raised by this whistleblower and others.”

The Department of Defence refused to comment.

“The Department does not comment on individual personnel cases,” said a spokeswoman.

“The Department and Defence Forces are fully committed to compliance with the Protected Disclosures Act, 2014.”

Since December, 2015, four whistleblowers have made protected disclosures to government about technicians’ exposure to chemicals at Casement Aerodrome.