tardant by the addition of a polyol containing about 5(/< phosphorus. The firm will not comment on the chemistry or mechanism of producing the skinned surface in the mold. Molds can be designed to produce a product with a surface almost indistinguishable from wood. Some potential markets for the product are in caskets, church pews, chairs, TV consoles, stadium seats, and cabinets. Although furniture will be the major use, the foams could also be used in the aircraft and auto industries. While the raw materials are slightly more expensive than those for regular methane foams, the end product in many cases can be designed to be lighter because of the strength of the skin. This permits an overall reduction in cost, according to Rubicon. Rubicon is backing its faith in the product with hard cash. The firm expects to build a 50 to 80 million pound-per-year MDI plant at Geismar, La., to be on stream in early 1972. Other MDI producers are Upjohn, which will soon have a 200 million pound-per-year capacity, and Mobay, which is expanding capacity from 150 to 200 million pounds of MDI and, in addition, is building an isocyanates unit at Baytown, Tex.
STRIKES:
Crimp the Recovery Just as all signs seemed to point upward in the chemical economy (C&EN, Aug. 31, page 9 ) , a major strike at General Motors and one possibly due for the railroads put a negative cast on the immediate future. Industry executives do not foresee a
rail strike of long duration, but they are worried about the effects on sales and the national economy from a prolonged walkout at GM. At Du Pont, for instance, head economist Charles B. Reeder says a rail strike is improbable. He says the rails are just too vital and that threats of a strike in the past have been met with executive action in Washington. However, the stoppage in Detroit is another matter. Mr. Reeder sees the chemical industry involved because of its paint, fabric, steel chemicals, rubber, plastics, and other businesses feeding into the auto industry. Du Pont supplies paint directly to the auto industry; other materials such as plastics go through middlemen. Much depends on how long the strike lasts. Up to a month, the economist believes, the effects should be minor. However, he fears the walkout will push past this point. Like Du Pont, Celanese singles out paints as the product most severely hit. Next in order of damage would be fibers and plastics. Overall, Celanese says it should suffer only slightly from the strike, since much of its automobile products do not go to GM. At Dow, chairman Carl A. Gerstacker says that "GM going down completely will be a jolt, but for us no single market is a large per cent of Dow's sales, so we don't see very much actual disruption of our business." A rail strike, the official continues, "would be a disaster. It would be impossible to operate with trucks. While the effects would vary, every major Dow plant would be seriously hurt." For the economy as a whole, including many other chemical markets
Many auto production lines have ceased operating because of union strike
THE CHEMICAL WORLD THIS WEEK
such as the consumer field, effects of the GM strike could be pronounced in the short run. U.S. Secretary of Commerce Maurice H. Stans says the strike is "regrettable," slowing down the economy, and affecting GM suppliers. The Commerce Secretary says the strike will not have a significant impact on growth in the third quarter, but if it goes into the fourth quarter, it could retard growth. However, long-term strike effects are not viewed with much alarm. On a possible rail strike, Secretary Stans comments that a walkout would "slow down, but not prevent, recovery of the economy." A U.S. Labor Department spokesman states there is no "real rail strike threat nationally" right now. President Nixon might let a rail strike go several days to point up the need for legislation. The railroads will be free to strike Sept. 23.
AIR POLLUTION:
Hydroxyl Radical Is Key * CHICAGO *£^£l £ air pollution puzzle by chemists at Ford Motor Co., Dearborn, Mich. In a relatively simple series of experiments, Dr. Donald H. Stedman and his colleagues have shown quantitatively that the hydroxyl radical, water, and carbon monoxide all play important roles in the sequence of steps leading to the oxidation of nitrous oxide to nitrogen dioxide. The findings, he says, raise questions about current methods of auto emission abatement and the applicability of previous ideas to smog formation. Dr. Stedman disclosed the Ford research before the Division of Water, Air, and Waste Chemistry at the ACS meeting last week in Chicago. Working with his colleagues, Dr. Earl D. Morris, Dr. Eric E. Daby, Dr. Hiromi Niki, and Dr. Bernard Weinstock, Dr. Stedman has determined rate constants and ratios for each step of the sequence leading to the formation of nitrogen dioxide. The importance of the hydroxyl radical chain reaction, Dr. Stedman notes, is that nitrogen dioxide can be formed even in the absence of hydrocarbons. The first step in the Ford chemists' proposed reaction scheme is the combination of water, nitrous oxide, and nitrogen dioxide to give nitrous acid. Nitrous acid subsequently undergoes photochemical decomposition to the hydroxyl radical and nitrous oxide. Carbon monoxide and the hydroxyl radical then undergo a reaction to form atomic hydrogen and carbon monoxide. Atomic hydrogen reSEPT. 21, 1970 C&EN
1?
acts with oxygen to form hydroperoxy radicals. These then react with ni trous oxide to produce nitrogen dioxide and regenerate the hydroxyl radical. The Ford chemists use high con centrations of carbon monoxide to ob tain quantitative rate constants, Dr. Stedman explains. Using typical atmospheric concentrations of carbon monoxide and their experimental rate ratios, the chemists estimate with a computer that carbon monoxide can contribute by as much as one third to the oxidation of nitrous oxide in the atmosphere. Hydrocarbon-carbon monoxide em ission control has thus far been the ma jor basis for air pollution abatement. As a result, total hydrocarbons from automobiles in the Los Angeles atmos phere, for example, have been sub stantially reduced, but nitrogen oxide levels have increased. Furthermore, there has been no substantial smog alleviation, Dr. Stedman claims. The Ford chemists thus suggest that ni trogen oxide control should take pri ority in the near future.
BRAIN:
New Enzyme Role _ ^ Ρ Η Ι Ο Α Ρ Π Extension of research ^ U n i U A I l U o n s k m pigmentation suggests that a previously known en zyme, mammalian peroxidase, may be involved in a vitally important meta bolic pathway in the brain. This is the catecholamine route from tyrosine through DOPA to dopamine and mel anin. Further research suggests that an abnormality in peroxidase activity may be involved in the pathobiology of Parkinsonism, a widespread neuro muscular disorder that causes gradual incapacitation. The disorder is pres ently treated with large doses of syn thetic L - D O P A
(a catecholamine) to
make up a deficiency presumed to be the cause of the condition. These findings were reported last week to the Division of Biological Chemistry at ACS's 160th meeting in Chicago by Dr. Leon Edelstein of the department of pathology at St. Vincent Hospital, Worcester, Mass. Collaborating with Dr. Edelstein were
Dr. Milton Okun, director of the dermatopathology laboratory, Boston City Hospital, and Dr. N. Or, also at St. Vincent Hospital. In previous research, Dr. Okun and Dr. Edelstein found that mammalian peroxidase from several tissues can convert tyrosine to melanin pigments with DOPA as a cofactor (C&EN, Sept. 22, 1969, page 3 8 ) . It had previously been thought that the con version of tyrosine to melanin inter mediates was triggered by tyrosinase, a copper-dependent phenol oxidase. Tyrosinase is not found in the brain, but tyrosine hydroxylase has been found to convert brain tyrosine to DOPA. The current findings in no way preclude the function of tyrosine hydroxylase but may present an added catalytic mechanism. Recognizing that the tyrosine-toDOPA conversion occurs in brain as well as skin cells, Dr. Edelstein and his associates investigated peroxidase ac tivity in homogenates of the right and left basal ganglia in a case of unilateral Parkinsonism and from normal brain, using acrylamide gel electrophoresis and quantitative disk densitometry. Indeed, they found a 20-fold decrease in specific activity of peroxidase in the diseased left basal ganglia compared to the right basal ganglia or compared to the normal brain. In additional experiments, peroxi dase localized in guinea pig brain neurons was found to mediate the histochemical and autoradiographic conversion of DOPA or tyrosine to melanin with DOPA as cofactor. This lends credence to the above gel work and shows that peroxidase activity is localized in the lysosomes (enzyme carriers) of neurons.
AGROCHEMICALS:
Relieving the Drudgery The synthesis and screening of large numbers of chemicals play a major role in the search for herbicides, pesti cides, and other agrochemicals which are less detrimental to the environ ment than some such chemicals used today. Knowledge of previous work is essential to prevent duplication of
^ r ^ f » ^ 7 v f ! , i f N . 5 \ T >-v s ^ v \ , \*.>f%>A
