WASHINGTON (AP) _ The Reagan administration is being urged to lead the industrialized world into new, tougher action against the chemicals that scientists say are destroying the Earth's stratospheric ozone layer.

The call for strict international controls on chlorofluourocarbons, or CFCs, is coming from senators, scientists and two quarters that often are in deep disagreement: environmentalists and chemical companies.

''We need a massive diplomatic mission,'' Sen. John Chafee, R-R.I., said Wednesday as two Environment Committee subcommittees heard renewed warnings that CFC's are depleting the ozone that shields humans from the sun's cancer- causing ultraviolet rays.

Committee members and witnesses took turns saying that the United States must take the lead to push other industrialized nations into taking stronger measures against CFCs than contained in last year's Montreal Protocol.

That agreement could lead to a freeze on global CFC production in 1999 at a level of 50 percent of the CFCs manufactured in 1986. To take effect, the protocol needs ratification by nations representing two-thirds of CFC production. So far, only the United States and Mexico have acted.

CFCs are widely used as refrigerants and industrial solvents and in the production of foam products. They also serve as propellants in aerosol cans, although such use was banned in the United States in 1977.

Witnesses said the administration should not only be pushing for ratification but also be lobbying for an emergency international gathering to consider a larger production freeze or even a ban on CFCs.

The protocol provides for a CFC review meeting sometime in 1990. Lee Thomas, administrator of the Environmental Protection Agency, said Tuesday he would press to have that meeting very early in 1990.

Sen. Max Baucus, D-Mont., called on President Reagan to make an accelerated schedule for CFC reductions a priority item this June when he and leaders of other industrialized democracies hold their annual economic summit.

Also calling for faster action was Sherwood Rowland, the University of California-Irvine professor who in the 1970s was one of the first scientists to warn of dangers posed by CFCs.

''Clearly the protocol is not going to do much of anything for 10 years,'' Rowland said. ''We need more rapid action than that.''

David Doniger, senior attorney for the environmentalist Natural Resources Defense Council, said a swift international response is needed in light of the conclusion announced March 15 by a panel of 100 scientists convened by the National Aeronautics and Space Administration.

The panel said ozone depletion is occurring faster than previously thought. Doniger said the losses cited by the panel already are at levels EPA has projected for the year 2050 under the production cuts specified by the Montreal protocol.

''I think we can attain a new worldwide agreement in a year and end the use of these chemicals by the end of the century,'' Doniger said.

Joining the call for a stepped-up diplomatic effort were representatives of two major U.S. producers of CFCs, E.I. DuPont De Nemours & Co., and Allied- Signal Inc.

''All of us need to work to get as many nations as possible to ratify the protocol as quickly as possible,'' said Marilyn Montgomery, vice president and general manager of Allied-Signal's Genetron Products.

Elwood Blanchard, DuPont's executive vice president, said his company believes that CFC-producing countries should be convened as soon as possible ''to review the scientific findings and to establish appropriate global responses to these findings.''

He and Ms. Montgomery said their companies have begun efforts to develop safe substitutes for CFCs, but neither could say when they might be available.

DuPont announced last week it was phasing out production of CFCs.