The federal government is considering its six national laboratories for temporary storage of radioactive medical waste in an effort to ease the crisis brought on by the closing of two of the nation's three low-level nuclear waste dumps.

Sources at the Nuclear Regulatory Commission said yesterday that it has been talking to the Energy Department about the possiblity of allowing liquid radioactive wastes from hospitals and medical research centers to be stored temporarily at disposal sites run by the department for its own nuclear waste. The commercial sites in Nevada and Washington that were closed in the last few weeks by the governors of those states and the remaining dump, in South Carolina, will not accept liquid wastes.

"I don't know what else we can do," one NRC source said yesterday. "The governors of the two states who've closed down their waste dumps are adamant about keeping them closed right now."

The sites in question are in Hanford, Wash., and Beatty, Nev., where most of the liquid radioactive wastes generated by hospitals and medical research centers doing nuclear medical research have been sent.South Carolina Gov. Dick Riley, in addition to banning liquid wastes, ordered the site at Barnwell not to accept any wastes that normally go to Hanford or Beatty.

NRC Chairman Joseph M. Hendrie spoke by telephone yesterday to Washington Gov. Dixy Lee Ray and Nevada Gov. Robert List, but he said he did not even try to persuade them to reopen the closed burial sites.

"Even if the two closed sites were to reopen this afternoon," Hendrie said, "there is still such a serious shortage of low-level disposal sites [and they are] so badly distributed that wastes have to be shipped all the way across the country."

A hurried two-hour meeting was called yesterday by the Federal Emergency Management Agency, set up last April after the Three Mile Island accident, to discuss possible emergency procedures if the Nevada and Washington dumps remain closed. At the meeting were representatives of the Energy Department, the NRC, the Transportation Department, the Public Health Service, the National Governors Conference, the American Medical Association and the Society of Nuclear Medicine.

"We agreed that if the two sites don't reopen by December, we'll begin to see a real reduction in nuclear medicine services," the NRC's Richard Cuningham said after the meeting. "It will then grow increasingly severe all the rest of the time these sites are closed."

The six national laboratories being considered as a temporary expedient in the crisis are operated by the Energy Department. They are involved in a wide variety of nuclear research and generate radioactive wastes ranging from plutonium for weapons to rare isotopes for medical research. The largest laboratories are at Brookhaven, N.Y.; Oak Ridge, Tenn., and Los Alamos, N.M.

Cunningham said the trouble for nuclear medicine will come in December when storage facilities begin to fill up at the factories that make radioactive pharmaceuticals. Trouble already exists at hospitals and medical centers that cannot store the radioactive tracers they use to follow chemicals through the bodies of humans and animals in their research.

Doctors point out that treatment of diseases like cancer involves the use of ionized beams that don't leave any radioactive wastes. Injections of radioactive iodine into the thyroid to treat glandular disease leave the medicine right in the thyroid.

"But there isn't any medical research in the world today that doesn't use radioactive tracers to track chemical and cellular processes in the body," said Harvard University's Dr. Mortimer Litt. "It's one of the god-sends of our age that allows us to follow a biological compound through the body."

After these biologics leave the body, they are mixed with flammable chemicals like toluene so they can be analysed. The result is that the waste fluids can't be kept around hospital labortories because they constitute fire hazards. Said Dr. Litt: "We generate enough of this waste in one week to close us down. The fire laws will not permit us to keep this stuff around any longer."