The health commissioner chosen by Mayor Eric Adams to lead New York City out of the Covid pandemic tendered his resignation on Monday, becoming the third top official to depart the administration this month amid multiple federal investigations of the mayor’s inner circle.

The commissioner, Dr. Ashwin Vasan, a mental health expert, cited a desire to spend more time with his family in his decision to step down, which takes effect early next year.

“As anyone with a family — or a chosen family — knows, you are never alone in service. My wife and three young children have served alongside me, bearing the brunt of my absence and shouldering so much,” Dr. Vasan said in a statement. “I’m grateful for their love and have chosen that now it is time to support them and their well-being.”

A City Hall spokesman, William Fowler, said Dr. Vasan’s departure was not related to the federal investigations, and the commissioner affirmed that in a brief interview.

“I’m so far away from that world, and my focus has been on the health of the city,” Dr. Vasan said of the investigations. “I don’t think anyone wants to see that kind of environment around us, because we want our mayor and the administration to be successful, because we want the city to be successful.”

Mr. Adams praised Dr. Vasan’s tenure.

“His expertise as a mental health expert, coupled with his training as a public health professional, have proven indispensable to our city over the past two and a half years as we’ve handled rising Covid rates, mpox outbreaks, and a mental health crisis both on our streets and in our schools,” the mayor said in a statement.