Washington (CNN) - Rep. Eric Massa, D-New York, denied reports Wednesday that he harassed one of his Capitol Hill staffers - announcing, however, that he would not seek re-election because of health concerns.
A spokeswoman for House Majority Leader Steny Hoyer acknowledged that allegations of misconduct against Massa, 50, were under review by the House Ethics Committee.
Hoyer spokeswoman Katie Grant said that a member of Massa's staff told Hoyer's staff about the allegations, and Hoyer gave the retired Navy commander 48 hours to take the matter to the Ethics Committee.
"Within 48 hours, Mr. Hoyer received confirmation from both the Ethics Committee staff and Mr. Massa's staff that the Ethics Committee had been contacted and would review the allegations," Grant said. "Mr. Hoyer does not know whether the allegations are true or false, but wanted to ensure that the bipartisan committee charged with overseeing conduct of members was immediately involved to determine the facts."
The online journal Politico reported earlier Wednesday that Massa was stepping down "amid allegations he sexually harassed a male staffer," and a senior Democratic aide later told CNN that the allegations involved a male staffer who was made to feel uncomfortable.
The aide, who spoke on condition of anonymity because the discussions among staff were private on a sensitive matter and because of the ongoing Ethics Committee investigation, said the allegation involved "a sexual implication."
Massa, who did not take questions during the media conference call in which he announced his decision not to seek re-election, addressed the allegations head-on and denied the report.
He described the report as "unsubstantiated without facts or backing."
But Massa, a U.S. Naval Academy graduate, did acknowledge using "salty" language in the workplace.
"Do I or have I ever used salty language when I'm angry especially in the privacy of my inner office or even at home? Yes, I have and I have apologized to those where it's appropriate," he said.
The freshman Democrat said he was announcing his decision to retire early in order to give candidates interested in replacing him sufficient time to plan a campaign.
Massa, a cancer survivor, told reporters that he was briefly hospitalized last December.
"I kept it private between myself and my immediate family," Massa said.
"It was a very intense and personal experience especially in light of having gone through this before."
Massa said he keeps up a brisk pace, "and my doctors have made it clear that I can no longer do that."
Massa is the 10th House Democrat to announce that he will not seek another term in the House nor run for a higher office in 2010. Seven House Republicans have also said they will outright retire at the close of the 111th Congress.
- CNN's Martina Stewart contributed to this report.