Facing "allegations of misconduct" that reportedly involve sexual harassment against a male staffer, freshman Rep. Eric Massa is resigning Monday.
"I own his reality," the New York Democrat said in a statement, admitting to using language that "might make a chief petty officer feel uncomfortable."
Massa went on to call Washington an "incredibly toxic atmosphere" and said the ethics committee probe "would tear my family and my staff apart."
"In that investigators would be free to ask anything about me going back to my birth, I simply cannot rise to that level of perfection," he said. "God knows that I am a deeply flawed and imperfect person."
The House ethics panel is reviewing a complaint by a male staffer who reportedly felt uncomfortable in a situation with Massa that had sexual overtones.
Massa said he is resigning with a "profound sense of failure and a deep apology to all those whom, for the past year, I tried to represent as our nation struggles with problems far greater than anyone can possibly imagine."
Massa announced Wednesday he would retire at the end of his term because of a recurrence of non-Hodgkins lymphoma, first diagnosed in 1996. He also addressed head-on the harassment allegations.
"The allegations are totally false. I am a salty old sailor," Massa, a former Navy officer, said at a news conference. "These are blogs that are saying that I am leaving because of charges of harassing my staff. Do and have I used salty language? Yes, and I have tried to do better."
He called the blogs "a symptom of the problem in this city."
The ethics committee received the charge against the New York lawmaker nearly a month ago.House Majority Leader Steny Hoyer's staff said his office was notified the week of Feb. 8 that Massa was facing the accusations.
Hoyer spokeswoman Katie Grant said in a written statement that Hoyer was "immediately informed" of the allegation and told his staff that Massa should refer the matter to the ethics committee within 48 hours, or he would do so himself.
"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.
On Wednesday, Hoyer acknowledged after Massa's announcement that he had "some indication" of the allegation, but didn't "want to go beyond that. And my presumption is it will be dealt with in the course of business."
Grant cautioned Hoyer does not know whether the charge has any truth behind it.
"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 ethics panel so far has not created an investigative subcommittee to review the charges. That could take days or perhaps weeks.
Hoyer did say the speculation surrounding Massa's departure could injure the party, or at least Congress, and even invoked the case of Mark Foley, the Florida Republican congressman who resigned after sending inappropriate electronic messages to underage House pages.
"I don't think it helps anybody in the institution -- any one of us on either side of aisle. It certainly didn't help Mr. Foley. When there were allegations about Mr. Foley or others, I think the institution suffers," he said. "And that's why it's so important that each of us conducts ourselves in such a way that it brings credit to the institution."
Massa is married and has three children. He retired from the Navy in 2001 after serving 24 years, including graduation from the U.S. Naval Academy. He served in Beirut, Bosnia and the Persian Gulf and worked for the House Armed Services Committee before joining retired Gen. Wesley Clark's presidential campaign in 2004. He defeated Republican Rep. Randy Kuhl in 2008 on his second challenge against the incumbent.
Massa is the 16th House Democrat to announce he will retire at the end of his term. Nineteen House Republicans are stepping down at the end of this Congress.
Fox News' Chad Pergram contributed to this report.