ELECTRODEPOSITION:
Two cathodic systems Two companies, Dow Chemical and PPG Industries, have made advances in electrodeposition of organic ma terials. Dow Chemical's Dr. Ε. Η. Wagener announced the first results of research on sulfonium latex coat ings to the ACS meeting in Los An geles. He believes that cathodically deposited latex materials will pro vide superior coatings and will cir cumvent some of the operational problems of anodic coatings. In particular, alkaline cathodic deposi tion is not as pH sensitive as anodic deposition and the sulfonium group does not leave ionic groups behind to contaminate subsequent opera tions. Further, cathodic deposition avoids the problem of anodic dis solution, which often causes stain ing of the coatings by metallic ions. Thus far Dow's announcement does not go beyond the concept as sup ported by laboratory work. How ever, Dr. Wagener does indicate that commercial exploitation of the proc ess is being considered by Dow. PPG Industries' cathodic electrocoating system is now in service in two pilot production lines. A PPG spokesman declined to identify the materials being used or the location of the pilot lines. Unlike electrophoretic spray sys tems, electrocoating employs a bath, usually a water emulsion of the coat ing materials, in which the object to be coated is either the anode or cathode in an electrolytic cell. A major problem remaining in the development of electrocoating sys tems is improving the throwing power of the systems to ensure uni form deposition in narrow recesses and on complicated shapes. PPG has limited its pilot production lines to the coating of small parts for ap pliances. The throwing power is still insufficient to use with confi dence for large objects such as auto bodies. PPG leaves little doubt, however, that adaptation of the cathodic electrocoating systems to more demanding jobs is only a mat ter of time. The principal advantage of ca thodic electrocoating, other than the higher quality of the coating itself, is the absence of great amounts of solvents which must be either re covered or vented to the atmo sphere. The water bath is also eas ily regenerated or cleaned, thereby avoiding further contamination of the environment with pollutants.
Dr. Barrett checks blood samples
DRUG ABUSE:
Chromatographic screening Hospital emergency room personnel can order gas chromatographic screening to identify abused drugs in serum or urine of unconscious pa tients, according to Dr. James Bar rett of Leary Laboratory, Boston, Mass. Dr. Barrett described his analysis scheme to an audience of several hundred clinical chemists in New York City at a seminar spon sored by Perkin-Elmer, Norwalk, Conn. Rapid analyses in emergency con ditions lead Dr. Barrett to favor gas chromatography over thin-layer chromatography for diagnosing drug overdoses in unconscious pa tients. Whereas thin-layer methods may require up to 24 hours, a screen for 18 barbiturates, narcotics, am phetamines, and psychoactive drugs is finished in 45 minutes. Accurate, rapid analysis is needed, he says, since treatments for one drug type sometimes aggravate the effects of other drugs. Nalorphine is sometimes used to counter mor phine, but the drug potentiates bar biturates, he says. Narcotics are in dicated by dilated pupils, but a blow on the head can also leave pupils dilated. Dr. Barrett divides drugs into classes of sedatives, amphetamines, narcotics, and psychoactive drugs. Sedative and psychoactive drugs
have the highest serum levels; am phetamines and narcotics are bet ter analyzed in urine. To screen for the barbiturates Noludar, amobarbital, pentobarbi tal, secobarbital, hexobarbital, Doriden, and phénobarbital, Dr. Barrett adds a known amount of Sedulon as internal standard to serum, extracts the serum with chloroform, and adds trimethylanilinium hydroxide (TMAH) plus a known amount of second internal standard (either methyl laurate or stéarate). TMAH converts barbiturates to volatile methylated derivatives. Departures from known Sedulon/methyl laurate or stéarate ratios alert the analyst to the possible presence of Noludar, which appears at the same retention time as does Sedulon. He screens for amphetamine and methamphetamine similarly, using Af-propylamphetamine as internal standard, added to urine before extraction, and using acetic anhydride to convert all amines to more volatile Af-acetyl derivatives in chloroform extract. For morphine and codeine, nalorphine is the internal standard, and acetylation of hydroxyl groups forms volatile derivatives. Heroin is metabolized to morphine, and appears as morphine in urinalysis. Nalorphine is an opiate antagonist, and thus is unlikely to be found in urine of persons suffering from opiate overdoses. The psychoactive drugs Librium, Valium, promazine, and Thorazine are extracted from chloroform. Lack of good internal standards requires the analyst to use one drug as a standard for determining one of the other three, since it is unlikely that one psychoactive drug cannot be ruled out. Darvon must be extracted for serum at a different pH from the first four, and Sedulon serves as the internal standard. EDUCATION:
Men know more science Men know decisively more about science than do women. Males and females of all ages from the southeastern U.S. know less about science than do their peers in the rest of the country. Young people from very large or very small cities know less about science than do those from middle-sized cities or suburbs. Those are some of the new findings released by the Education Commission of the States, Denver, Colo., in a report on the National AssessAPRIL 12, 1971 C&EN
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Chemical world This week ment of Educational Progress. The report is an initial analysis of results obtained in 1969 and 1970 when NAEP surveyed more than 80,000 people aged nine, 13, 17, and 26-35 to determine their knowledge of science, writing, and citizenship. The preliminary report on the science results—issued last July (C&EN, July 13, 1970, page 11)—indicated that textbook knowledge of science reaches a maximum near age 17, but that science knowledge gained from experience continues to increase with age. The new analysis elaborates on the initial report by giving the results in terms of sex and the geographical region and size of the city in which the respondent lives. (A future report will make further comparisons on the bases of parental education, color, and the type of community.) At the age of nine, ECS says, boys and girls have about the same knowledge of science. In the 26-35 age group, however, males were able to provide the correct answer to 9.7% more questions than females —despite the fact that females did 2.3 °/o better on questions about biology and reproduction. On a geographical basis, southeastern respondents of all ages scored 5.0% below the national average. The best scores were obtained by young people in the Northeast (2.0% above the average) and young adults in the West (2.6% above the average). In large cities, all age groups were between 2.4 (young adults) and 4.8% (nine-year-olds) below the national average. In small towns, all groups were closer to the average, and in medium-sized cities, all were slightly above the average. In the urban fringes, the groups were between 2.4 (17-year-olds) and 3.4% (13-yearolds) above the average. NAEP provides only descriptive results, so no conclusive reasons for the differences are available. The main purpose of the survey, says ECS, is to provide a baseline so that future surveys can measure the progress of U.S. education. CANCER:
Promise of platinum "Remarkable ability" to cause remissions in a variety of tumors in test animals, and one of the compounds —c/s-dichlorodiammineplatinum(II)—that has such ability will soon be tested on human cancers, Dr. Barnett Rosenberg revealed at 14 C&EN APRIL 12, 1971
the American Cancer Society's seminar for science writers in Phoenix last week. Dr. Rosenberg, a Michigan State University biophysicist, added that the compounds may be synergistic with alkylating agents already used to treat tumors, and that the platinum drugs' side effects appear to be "minimal and reversible." The way platinum's antitumor potential was discovered demonstrates the value of basic research, Dr. Rosenberg asserts. He explains that he and Loretta Van Camp were studying the effects of an electrical field on bacteria, using supposedly inert platinum electrodes. When a field was applied to a culture of E. coli, the organisms did not divide but continued to grow and to form long filaments. Two of Dr. Rosenberg's associates, Dr. Thomas Krigas and Dr. Andrew Thomson, found that platinum ions were combining with the culture medium to form a compound that allowed the cells to grow but kept them from dividing— even in the absence of the electrical field. "Because these compounds inhibited cell division in bacteria, we reasoned they might also inhibit cell division in tumors," Dr. Rosenberg says. The platinum compounds were first tested on sarcoma 180 tumors in mice. Even when the tumors were allowed to grow large before treatment, Dr. Rosenberg says, "a single injection caused complete regression in nearly every animal tested; 11 months later, the mice remained immune to a rechallenge with the same tumor." When the first tests were successful, the MSU workers submitted some of the compounds to the National Cancer Institute for screening against other types of tumors. According to Dr. Rosenberg, NCI's first tests showed that single injections of one of the drugs caused tumors to disappear in four of 10 mice with L-1210 leukemia. Since then, he says, U.S., English, and Czechoslovakian scientists have tested platinum compounds against a variety of animal tumors; their reports indicated that "the platinum compounds had one of the broadest spectrums of action of any class of antitumor agents yet discovered." The platinum drugs, like other antitumor agents, mainly affect rapidly dividing cells—bone marrow and the lining of the intestines, for example—and must therefore be considered somewhat toxic.
I FERTILITY:
Effects of DDT Few compounds have been subjected to the same degree of scrutiny and critical evaluation as to their potentially harmful effects on the biosphere as DDT has been during the past few years. Now, in what constitutes the first possible instance of a delayed effect of the chemical, it has come into the limelight again because of the likelihood of its being a contributing factor in some cases of female sterility. Sparking what will likely become a new phase in the controversy surrounding the pesticide is the finding by Dr. William L. Heinrichs and Dr. Ronald J. Gellert at the University of Washington medical center's obstetrics and gynecology department that the o,p' isomer of DDT, when injected into newborn female rats, causes the animals to develop multiple cysts in their ovaries after they reach adulthood. Indeed, the rats exhibit all the symptoms of persistent estrus syndrome. This, Dr. Heinrichs points out, is the closest experimental model of polycystic ovary syndrome in humans, a condition responsible for sterility among a significant percentage of the nonfertile women examined each year at the university's clinic in Seattle. The researchers injected subcutaneously 1 mg. of DDT into rats on the second, third, and fourth days after their birth, a fairly massive dose in relation to their body weight. After the rats reach puberty, their sexual cycle is normal for a time. Then, anovulation sets in, cysts appear in the ovaries and corpora lutea fail to develop. This condition closely matches the effects of injected estradiol on the hypothalamus during the critical period of its differentiation, Dr. Heinrichs and Dr. Gellert told the American Cancer Society's 13th annual seminar for science writers in Phoenix, Ariz. And since estrogens influence the differential cycling pattern capacity of that gland, the scientists reason that DDT, too, might adversely affect the hypothalamus. One hypothesis that they propose is that DDT, entering the environment of a human fetus, might alter the program of development of the fetus's hypothalamus. Then, at the onset of puberty or shortly thereafter, aberration of the gland's secretion would foster the occurrence of polycystic ovary syndrome.
