WASHINGTON – Trying to ratchet up pressure on Congress, the White House on Friday detailed what it said would be the painful impact on the federal work force and certain government assistance programs if “large and arbitrary” scheduled government spending cuts are allowed to take place beginning March 1.

They include layoffs or furloughs of “hundreds of thousands” of federal workers, including FBI agents, U.S. prosecutors, food safety inspectors and air traffic controllers, White House budget officials said at a briefing and in a fact sheet that included these examples of what the cuts would mean:

70,000 young children would be kicked off Head Start, 10,000 teacher jobs would be put at risk and up to 2,100 food safety inspections might have to be canceled.

Up to 373,000 “seriously mentally ill adults and seriously emotionally disturbed children” would go untreated, up to 1,000 fewer National Science Foundation research grants affecting some 12,000 scientists and students could be threatened, many small business loans denied, workplace safety inspections curtailed, federally assisted programs like “Meals on Wheels” slashed and 125,000 low-income renters put at risk of losing government-subsidized housing.

About 424,000 fewer HIV tests could be conducted by state agencies working with the Centers for Disease Control and some 100,000 formerly homeless people, including veterans, would be removed from their current housing and emergency shelter programs.

The so-called mandatory sequester cuts are a “serious threat to national security, domestic programs and the economy,” Office of Budget and Management official Danny Werfel told a White House briefing.

The spending cuts were originally to take place beginning Jan. 1, but were put off until March 1 in a last-minute deal between President Obama and Congress to avert a New Year’s Day “fiscal cliff” of tax hikes and spending cuts.

At issue are $1.2 trillion of additional spending cuts over the next 10 years, including about $85 billion this year.

Obama has called for a small package of spending cuts and measures to close tax loopholes and put off the deadline again. But Republicans have so far said no.

“We agree the sequester is the wrong way to cut spending,” Brendan Buck, spokesman for House Speaker John Boehner, said Friday. But, he added: “The president got his higher taxes on the wealthy last month — with no corresponding cuts. The tax issue has been resolved.”

White House press secretary Jay Carney dismissed such arguments as “convenient spin, but it’s also a lot of baloney.”

In the Senate, majority-party Democrats are discussing ways to raise new revenues and curb spending to replace the cuts and aiming for a vote just before March 1. They want to cut spending as well, including direct payments to farmers that are seen as hard to defend.

“It should be a mixture,” said Sen. Charles Schumer, D-N.Y.