LONDON, ONT. -- Comments about another possible privacy breach by the Middlesex London Health Unit (MLHU) are straining the relationship between county administration and the region’s public health agency.

During the public portion of Tuesday’s meeting of Middlesex County council, county CAO Bill Rayburn explained that his staff were repurposing file folders left inside the 50 King St. by the MLHU when they discovered a letter.

“We actually came across a document, that is a human resources letter, that fell out of one of the file folders.” Rayburn adds it “contained private and personal information about an individual.”

The health unit responded to Rayburn’s public comments about the document with a letter from its lawyer.

It reads in part, “Disclosure of that information in a public meeting could only have been for the purpose of embarrassing MLHU and Dr. Mackie. We write to require that any such confidential information and any related materials found in or around Dr. Mackie’s desk should be delivered to him at the MLHU offices immediately, without further inspection or comment on your part.”

In March, the MLHU moved out of the county-owned office building to a new headquarters inside Citi Plaza, leaving numerous desks, computers and medical items behind.

Last week, the Information and Privacy Commissioner of Ontario determined that data discovered during the repurposing of some computers represented a privacy breach.

At the time, the commissioner remarked, “The county acted responsibly by notifying my office and ensuring that any potential further breaches of privacy were immediately contained.”

Rayburn told county council he will again seek guidance from the privacy commissioner.

Rayburn’s comments about the ‘HR letter’ came while he responded to a question from a politician about the status of the 50 King St. building.

Rayburn also explained that the process remains on target, but the discovery of the document could impact the budget and timeline.

“We’ve had to slow down a little bit now and really look at things going out to make sure we don’t have an inadvertent data breach,” Rayburn added, “So that’s really made things more time consuming and expensive on our part.”

CTV News has not seen the document in question and cannot confirm the type of information it contains.