The U.S. Civil Rights Commission said yesterday there is "widespread" age discrimination against both young and older persons in 10 of the federal government's major social programs, including Medicaid, legal services and the job-creation and placement program, authorized by the Comprehensive Employment and Training Act (CETA).

In a 112-page study that took 15 months, the commission urged Congress to raise the retirement age for workers in federally funded programs from 65 to 70, and to grant federal executives the authority to switch such programs from one state or local agency to another if state or local administrators discriminate on the basis of age.

About a fourth of the federal budget now goes into programs specifically for older people, including Social Security, Medicare and various kinds of pensions.

However, the commission studied programs that are supposed to benefit all age groups -- programs such as food stamps, community health and mental health centers, and grants for basic adult and vocational education.

It said it found unjustifiable age discrimination, especially against persons over 65, in all of them.

"We are shocked at the cavalier manner in which our society neglects older persons who often desperately need federally supported services and benefits," the commission said in a statement accompanying the report.

Chairman Arthur B. Flemming, who also heads the Administration on Aging went even further at a news conference.

"This has been an eyeopener as far as I am concerned," he said. "It can be described only as insidious, and the kinds of reasons that are advanced are just kind of cold-blooded. They're impersonal . . . a lazy person's device for dealing with a very difficult administrative problem."

Some examples of discrimination the commission said it found include:

Mental Health Services, "one of the most glaring examples of discrimination on the basis of age." People under 15 and over 65 are "seriously underrepresented," the commission said, often on the grounds they are harder to deal with than people 25 to 44.

The commission cited experts' testimony that people over 65 have more mental health problems than any other age group.

CETA administrators place the highest priority on finding jobs for the most easily employed, generally defined as people 22 to 44, but in some cases discriminating against those over 34.

Labor Secretary Ray Marshall, who administers the CETA program, when asked for comment said there is "no question" that CETA was inadequately concerned with the elderly before he took office a year ago.

He cited a problem also noted by the commission: who gets hired under CETA is left largely to state and local governments, which often impose their own age restrictions.

People over 65 make up only 4 per cent of the participants in the Adult Basic Education Program, even though they make up at least 35 per cent of those eligible.

Community health centers tend to emphasize preventive health care for younger people.

The study said administrators gave many reasons for neglecting older people, including the argument that limited funds ought to be invested in the young because they provided a better return on the government's money.

"Such beliefs conflict with the concept of the dignity and worth of the individual . . . ," the commission said.

It also found that state and local laws can lead to age discrimination in federal programs. It cited Missouri, which passed a child abuse and neglect law with strong penalties for administrators who didn't enforce it, but then didn't provide new funds for the administrators to work with.

They shifted money from adult services to enforce the new law, the study.

Commission Vice Chairman Stephen Horn, who said he agreed with 98 per cent of the report, took exception to a proposal to raise the retirement age at colleges and universities, and to a recommendation that legal fees be paid for those filing age discrimination suits.

Horn, an official of California's state college system, said letting older professors, most of whom are white males, stay on until age 70 would ". . . perpetuate the ethnic, racial and sexual complexion of American higher education for still another generation."

Free legal help for those filing suits would result in "further clogging of the courts . . .," he said.

The commission made the study at the request of Congress, which in 1979 banned "unreasonable" discrimination on the basis of age.

Congress asked the commission to report on the extent of age discrimination and delayed implementation of the law until Jan. 1, 1979, to give the Department of Health, Education and Welfare time to write regulations based on the commission's study.