the carcinogenicity guidelines of other federal agencies, particularly those used by the Environmental Protection Agency last year to ban certain pesticides. They will serve as the basis of NCFs advice to federal regulatory agencies when it is asked to assist in determining the hazard of chemicals in the environment. There is no simple and universal definition of carcinogenesis, the guidelines say. The possible hazard of each chemical substance must be evaluated individually for each intended use. However, since most chemicals that are carcinogenic in humans are carcinogenic in animals as well, a demonstrated animal carcinogen must be taken as a carcinogen in man unless there is strong evidence to the contrary. To establish positively carcinogenicity in humans or animals, the guidelines say there must be an increase in the number of malignant tumors formed in organisms treated with the chemical over a control group. Formation of benign tumors or increased growth of already established tumors identifies the agent as a possible carcinogen whose health effects should be studied further. Experiments must be designed so that the only experimental variable is the administration of the suspected carcinogen. And animal data must be reproducible, either in another species or in the same species in another laboratory. The Ames mutagenicity test and other short-term and in vitro tests currently under development are promising, the subcommittee finds. However, as yet none of these tests is specific enough to prove carcinogenicity, but they can be very useful as a screening tool for potential carcinogens, the subcommittee working paper says. D
Kissinger rejects nuclear export curbs Secretary of State Henry A. Kissinger last week told the Senate Government Operations Committee that although U.S. efforts to devise multinational safeguards and controls on exported nuclear material have "met with a significant degree of success," nuclear proliferation still remains "one of the most urgent problems facing the U.S. and the world community." And he warns that Congressional adoption of recent proposals to place severe restrictions on the U.S. export of nuclear technology and material "would seriously set back, rather than advance, our nonproliferation efforts." 8
C&EN March 15, 1976
slight. Even if some of the proposals win the approval of the Government Operations Committee, they probably would have to be referred to the Joint Committee on Atomic Energy, which opposes them. D
Laser enrichment test unit planned
Kissinger: urgent problems
The proposals Kissinger refers to were aired at committee hearings earlier this year and include one from Dr. David E. Lilienthal, first chairman of the Atomic Energy Commission, that the U.S. unilaterally and immediately order a complete stop to the export of all nuclear devices and materials. Also proposed was an embargo on nuclear transfers to all countries that are not a party to the nuclear nonproliferation treaty. Adoption of any of these proposals, Kissinger told the committee, would "damage U.S. political relationships well beyond the nuclear area with a large number of countries" that have long-term nuclear supply arrangements with the U.S. He adds that they would "reduce the influence the U.S. is now able to bring to bear in support of our nonproliferation efforts inasmuch as it is unlikely that such proposals would be supported by all major suppliers and might well result in the breakdown of supplier cooperation and a return to relatively uncontrolled competition among other supplier countries." In addition, Kissinger says the Administration "cannot support" a much milder proposal now under consideration by the committee aimed at tightening and reorganizing U.S. government supervision of nuclear exports. This bill, S. 1439, cosponsored by committee chairman Sen. Abraham A. Ribicoff (D.-Conn.) and the committee's ranking Republican, Sen. Charles H. Percy (R.-Ill.), would, among other things, consolidate all peaceful nuclear export licensing and approval authority in the Nuclear Regulatory Commission and give Congress final approval power on a nuclear export application that raises substantial foreign policy considerations that NRC cannot adequately resolve. The Administration's opposition and the slim, but growing, support for the proposals in Congress means that their chances for enactment are
Enriching uranium with laser energy may move yet another stop toward reality, judging from a recent industry action. Previously secretive about how far along development of its process was, Exxon Nuclear has disclosed that it has filed a license application with the Nuclear Regulatory Commission to build a $15 million facility to perfect a technique it and Avco Corp. have been working on since 1971. Jersey Nuclear-Avco Isotopes Inc., an 80/20 joint venture of Exxon and Avco, will occupy the experiment station planned for Richland, Wash. Ground breaking is scheduled to begin in early 1977 if necessary permits are obtained on time. Startup of the lab is slated for 1978 or 1979. In announcing the plans to build the test facility, R. L. Dickeman, president both of Exxon Nuclear and of the joint company, said that "the fundamental technology has been proved thus far at the research level, but scaled-up experimentation of the integrated system is now required; it ultimately must be proved in an engineering and economic sense." This latest move seems to confirm speculation last year that Jersey Nuclear was closer to scaling up a laser isotope enrichment process than many observers had believed (C&EN, June 9,1975, page 26). Other laboratories are seeking laser methods for uranium enrichment, including two University of California units— Lawrence Livermore Laboratory and Los Alamos Scientific Laboratory. Currently, uranium enrichment for nuclear fuel is carried out by gaseous diffusion in three plants operated by the Energy Research & Development Administration. Gaseous diffusion, however, requires vast amounts of electric power. By most estimates, use of lasers would greatly reduce energy needs for uranium enrichment, and thus the cost of nuclear fuel. At the same time, a successful laser enrichment process could short-circuit development efforts currently under way with the gas centrifuge method of uranium enrichment. The gas centrifuge method is seen as more efficient than gaseous diffusion, although probably not as efficient as a laser process. D
