The VA hospital in St. Louis is investigating claims by the former chief of psychiatry that veterans often wait a month or more for mental health treatment because psychiatrists and other staff members are so lax in their work.

Dr. Jose Mathews claims in a federal whistleblower complaint filed last year and in an interview with The Associated Press on Monday that he was demoted because of a staff "mutiny" that followed his efforts to make employees work harder and more efficiently.

The concerns prompted a joint letter Monday from Missouri's U.S. senators, Republican Roy Blunt and Democrat Claire McCaskill, to Veterans Affairs Secretary Eric Shinseki. The letter seeks information on the number of mental health providers at the St. Louis VA, their workload, and in how timely a manner patients are being seen.

"If true, these claims would demonstrate an unacceptable lack of leadership at the VA in St. Louis that is putting the health and safety of veterans at risk," the senators wrote.

Marcena Gunter, a spokeswoman for the hospital, said the complaints are under investigation.

"We take these allegations seriously," Gunter wrote in an email. "The St. Louis VA Medical Center leadership is aware of and is addressing the alleged issues."

Mathews took over as chief of psychiatry in November 2012. He said he was astonished to learn of the limited workload of psychiatrists — typically about six patients per day. He said they should be seeing at least twice that many.

"I could account for only a four-hour workday," Mathews told The Associated Press.

The amount of time spent with each patient varies but the vast majority of visits are 30 minutes, Mathews said.

Meanwhile, the average wait time for those who are seeking help for mental illness is nearly 30 days, Mathews said.

"There is no conceivable reason a full-time psychiatrist should be seeing just six patients in a day," Mathews said. "It was causing this huge delay in access to care."

Mathews said he implemented several changes aimed at providing more timely treatment, but his efforts were met with opposition by staff. He was able to increase the average number of patients per psychiatrist to around nine per day by July. But in September, he was reassigned to a compensation and pension evaluation team.

"I was called in by the chief of staff," Mathews said. "The words he used were, 'There was a mutiny.'"

Mathews raised other concerns in his whistleblower complaint and in a letter to McCaskill last month. He cited data that "puts our facility well above the national average for productivity. This misleading data provided for budgetary funding appropriations does not correspond with the reality," Mathews wrote to McCaskill.

He also questioned:

—Why bonuses are paid to virtually all staffers, regardless of their productivity.

—Why his requests for investigations into the deaths of two veterans were turned down.

—Whether staff intentionally failed to report a psychiatric patient's suicide attempt that occurred while an accreditation commission was visiting the hospital last year.

The VA hospital in St. Louis has been under scrutiny before. In 2010, faulty sterilization at the center's dental clinic raised concerns that 1,812 veterans were potentially exposed to hepatitis and HIV. Testing eventually found no link to either disease in any of the patients.

Another cleanliness concern arose in February 2011 when the hospital shut down its operating rooms because rust stains were found on surgical equipment. Surgeries resumed several months later after the faulty equipment was cleaned or replaced. The VA revised polices and opened a new $7 million sterile processing lab in May 2012.

The complaint by Mathews comes amid reports that as many as 40 veterans died while awaiting medical care from the VA hospital in Phoenix.

"The underlying principle is what is corrupt," he said. "You have an obsessive desire to look good on paper with no regard to whether care is good or not."