ask 'Where do we go from here?' " Schneider says. Some changes of direction may well be needed; Press sees many symptoms of decay. "Between 1968 and 1975, the federal government's funding of basic research declined 20% in constant dollars/' he says. Furthermore, industrial labs are moving away from exploratory research and toward more "defensive" research—protecting their products against federal regulations and refurbishing old products instead of risking new ones. "By the time the decay in basic research becomes apparent," Press points out, "recovery could take a decade." D
New chemical detected in smog formation The first example of a new class of small-ring compounds has been detected as a short-lived intermediate in photochemical smog reactions. The compound, dioxirane, was found by a team of chemists and physicists at the National Bureau of Standards studying the reaction of ozone with ethylene—an important reaction in smog formation. That dioxirane is formed at all is causing re-evaluation of currently accepted models of the reaction mechanism of olefins with ozone in polluted air. The dioxirane molecule is very simple looking: H. H'
,0
c; I
^0 "It's the sort of molecule that you would expect undergraduate students to put down in reaction mechanisms," says Dr. Joel Leibman, a theoretical chemist studying small-ring compounds at the University of Maryland, Baltimore. "And you also would expect more advanced students to look at it and say, 'No, it can't be formed,' " he continues. "Seeing it actually found is very, very nice chemistry." The NBS scientists found the compound as part of an investigation of the ozone-ethylene reaction. Chemists John T. Herron and Robert E. Huie had earlier determined by computer analysis of reaction rates and product concentrations in this system that 90% of the reaction products were molecular fragments rather than free radicals. This finding contradicts most current reaction mechanisms, which call for formation of large numbers of free radicals, but it supports a mechanism proposed in
NBS physicists Suenram (left) and Lovas discuss the formation of the dioxirane molecule, which they detected for the first time using low-temperature microwave spectroscopy. The compound's existence was confirmed by chemists Huie, Martinez, and Herron (left to right in photo on right) by low-temperature mass spectrometry
1975 by Dr. W. R. Wadt and Dr. W. A. Goddard III, which has dioxirane as an intermediate. Collaborating physicists in this work, Dr. Richard D. Suenram and Dr. Frank J. Lovas, performed the ozone-ethylene reaction in a specially constructed microwave absorption cell cooled to -196° C. Under these conditions, the dioxirane molecule is stable enough to be detected by microwave spectroscopy. Dr. Herron, Dr. Huie, and Dr. Richard I. Martinez then repeated the experiment at low
temperature and found by mass spectroscopy analysis an intermediate whose charge-to-mass-ratio is consistent with dioxirane. What the discovery does for the chemistry of smog is to "really nail down beautifully" the notion that free radical formation is not the most important part of the reaction of ozone with olefins, Herron explains. Suenram and Lovas have tried to form other dioxirane compounds, particularly the methyl and fluorine derivatives, so far without success. D
Plan aims at better toxic chemical control To better coordinate the govern- I into which information can be shared ment's campaign to regulate toxic among various federal agencies chemicals, the federal Toxic Sub- "without placing unnecessary burstances Strategy Committee panel dens on regulated industries." More early this month laid out its master than 30 federal agencies collect such plan to pull together federal safety data in one form or another, but free efforts. The panel, composed of sci- exchange of information is limited entists and nonscientists from 16 because of laws and agency practices federal agencies and chaired by Gus- to protect trade secrets. The comtave Speth of the White House mittee will examine which of these Council on Environmental Quality, barriers can be lowered. The federal policy for carcinogenic singled out several broad areas for scrutiny: risk assessment is likely to affirm the • Chemical carcinogenesis—the utility of high-dose, long-term animal committee will give top priority to studies (such as those used to test working out a single set of principles saccharin) in determining carcinofor identifying chemical carcinogens. genicity. High-dose animal experiAccording to the committee, a lack of ments have long been accepted by such principles has led to much public toxicologists as direct evidence of a chemical's ability to produce human confusion. • Federal research—although the cancer at lower doses. CEQ's Speth, formerly a lawyer government conducts and supports much research on toxic chemicals, with the Natural Resources Defense federal authorities are not always Council, declares: "For the first time certain that research is adequate and federal authority over hazardous well designed. The committee will chemicals spans the entire cycle of chemical production and use. We now look into improvements. • Data collection—because toxic can begin to develop comprehensive chemicals regulation requires exten- strategies—using both regulatory and sive information about chemical nonregulatory approaches—to make production, use, sales, employee ex- sure that human health and the enposure and health, and environmen- vironment are not subject to unnecD tal effects, the committee will look I essary risks." Nov. 14, 1977C&EN
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