The Chemical World This Week
1975 ENGINEERING GLASS SMALLEST IN YEARS The ranks of new U.S. engineers, including chemical engineers, took a nosedive last June. The 1975 total engineering class was the smallest since 1968. This year's class may be a little larger, but new graduates apparently are getting fewer job offers than did their predecessors a year ago. The 1975 drop in new graduates from 1974 was 8% for all B.S. engineers and 10% for B.S. chemical engineers, the Engineering Manpower Commission of the Engineers Joint Council in New York City finds in a tabulation from U.S. engineering schools issued last week. New bachelor chemical engineers numbered 3167 last year, 8% of the 38,210 total of all new bachelor engineers. The 1975 graduating total for B.S. chemical engineers is the fifth straight decline since the recent peak of 3730 in 1970. For total new B.S. engineers, the 1975 class represents the third consecutive decline since the recent high of 44,190 in 1972. The decreases spread through higher degrees too. At the master's degree level, there were 1050 new chemical engineers in 1975 of a total of 15,773 new M.S. engineers of all types. In 1974 there were 1053 new M.S. chemical engineers and 15,885 total M.S. engineers. For new Ph.D.'s, 366 in chemical engineering in 1975 compared to 403 in 1974, and 3138 in all engineering in 1975 compared to 3362 in 1974. These numbers of new Ph.D.'s in 1975 were considerably lower than for any year since 1968 for both chemical engineering and engineering as a whole. The 1975 graduating class may turn out to be a low point in numbers for total engineers, however. The Engineering Manpower Commission
B.S. chem engineering gradsoff 10% in 1975 B.S.
ENGINEER
GRADUATES
Academic year 3
Chemical
All types
1968
3234
38,002
1969
3433
39,972
1970
3730
42,966
1971
3626
43,167
1972
3600
44,190
1973
3586
43,429
1974
3523
41,407
1975
3167
38,210
a Ending June 30. Source: Engineers Joint Council
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C&EN March 15, 1976
expects the 1976 class to be slightly larger because of a rapid recovery in freshman enrollments since the 1970-71 slump. Still, the engineering graduates this June might not find the job market quite as rich as in 1975. In a puzzling finding, the College Placement Council, Bethlehem, Pa., revealed last week that its latest survey shows a 23% drop in job offers to new B.S. engineering graduates from a year ago. Salaries offered, however, are still on the rise, especially for new chemical engineers. Job offers from the chemical and drug industries also are resisting the overall drop. For perspective, CPC notes that the drop in offers for all graduates in its latest survey is less than the drop first indicated in a survey released in January. Offers to women graduates at all levels are running well ahead of a year ago. EMC also notes rapid growth in the numbers of new women and minority engineers in its 1975 survey. Even so, the absolute figures are small. Among
all bachelor degree engineers, there were 2% women, 2% blacks, 2% Spanish surnamed, 2% Oriental, and 0.1% American Indian. The percentages were also low for chemical engineers—4% women, 1% blacks, 1% Spanish surnamed, 2% Oriental, and 0% American Indian. At higher degree levels the percentages of women and minorities tend to be even lower for both chemical engineers and for all engineers. Notable exception is for Orientals, whose relative ranks improved a little at the masters level and again at the doctoral level. In a companion survey issued last week, EMC finds a 20% addition to regular engineering graduates in the form of graduates with bachelor of technology degrees. EMC also finds about three times as many two-year graduates with associate degrees as four-year technology degree holders. However, the percentage of chemical technology graduates is tiny—1 to 2% at the two-year degree level and nil at the four-year degree level. D
Study fails to prove eye amate hazard Cyclamates have received about as clean a bill of health as they are likely ever to get from a special, five-member National Cancer Institute committee. In a report presented to the Food & Drug Administration last week, the committee, which spent nine months reviewing all available data on cyclamates, concludes that "present evidence does not establish the carcinogenicity of cyclamate [s] or [their] principal metabolite, cyclohexylamine, in experimental animals." But the committee says that no conclusion can be made regarding the question of cyclamates' potential carcinogenicity in humans because of lack of epidemiological data. And it is "concerned over the implications of the increased incidence of tumors in the urinary tract of cyclamate-fed animals from several studies, even though those increases were not statistically significant." It is not clear, the committee says, whether this represents a weak carcinogenic response or a random variation. In its report, the committee says that it "fully recognizes the logical impossibility of proving that cyclamates, or anything else for that matter, cannot cause cancer" and admits
that the question of cyclamates' carcinogenicity may not be answerable using present-day methods. It notes that the cyclamate question has pushed the technology of carcinogenicity testing to its limit and questions whether further animal testing to resolve the remaining uncertainties would really prove anything. When the committee tried to design a test protocol that would resolve these uncertainties, it came up with one that called for having animals of both sexes of two rodent species exposed to three dose levels of cyclamates in utero, with the treatment continued for the rest of their lifetime. Since cyclamates are, if anything, weak carcinogens, in order to obtain a 1% detection difference in bladder tumor incidence between treated and control animals, a total of 51,968 animals would be required for the study. Even if such a study could be done, at an estimated cost of $8 million to $10 million, the committee points out that a negative result still could be questioned. Abbott Laboratories, U.S. manufacturer of the sweeteners, says it is gratified at the committee's decision that cyclamates are not carcinogenic in test animals. And, it says now that
the cancer question has been resolved, it sees no reason why FDA should delay any further in acting on its petition to have cyclamates reapproved. FDA says it will evaluate the report along with other information dealing with possible cyclamate-associated health hazards, such as possible cyclamate-induced changes in the reproductive system of test animals, before making a decision on whether to allow cyclamates back on the market. The decision is not expected before midyear, at the earliest. D
Birth defects: vinyl chloride suspected The suspicion that parental exposure to vinyl chloride may be responsible for certain types of birth defects is being further investigated by the National Center for Disease Control. In March 1975, a study by the Ohio Department of Health suggested that a relationship existed between increased rates of central nervous system malformations in infants and exposure of their parents to vinyl chloride. The Ohio study is the only one in which vinyl chloride has been suggested as a possible cause of birth defects. A followup study by the disease control center confirmed a moderate increase in malformations in Painesville, Ohio, but could not establish any association between birth defects and exposure to vinyl chloride. In view of the Painesville study's being a hospital-based study and not a community-based study, the center has now elected to follow up with a second, community-based study. The choice for the study is Charleston, W.Va. Both Charleston and Painesville have plants that produce vinyl chloride and convert it to polyvinyl chloride. Like Painesville, Charleston also has exhibited an increased incidence of birth defects of the central nervous system in infants. Although workers in the plants would be expected to exhibit the greatest susceptibility to any effects from vinyl chloride exposure, people living in the region of the plants also may be susceptible. Both workers and nonworkers are being interviewed by the disease control center. The center recognizes that vinyl chloride is a known carcinogen and that in test animals has been shown to damage genes. One suggestion is that vinyl chloride may damage male sperm cells in roughly the
same way that it damages the genebearing chromosomes of white blood cells. The Charleston study is being based on interviews with two populations. One is composed of parents of children born with birth defects and the other of parents of children with no birth defects. Even while the Charleston study is in progress, the Environmental Protection Agency and the American Public Health Association are planning a joint investigation of the geographic distribution of possible health hazards around vinyl chloride plants. The site for this study has not been chosen yet. The two organizations will examine the incidence of all known effects of vinyl chloride exposure around the plants, with emphasis on birth defects. Although most of the hazard data on vinyl chloride is based on study with laboratory animals, there is direct, but inconclusive evidence, that workers in PVC plants do suffer from greater chromosomal breakage than do nonworkers. Whether this can be attributed to exposure to vinyl chloride or to some other factor is not yet known. D
Powerful laser fusion project launched A $46.5 million, five-year program to build and test a new laser fusion system is being launched at the University of Rochester's Laboratory for Laser Energetics. Focus of the program is a "third generation," 10-kilojoule neodymium glass laser system, dubbed "Omega X," which will be among the world's most powerful fusion research systems. Backers of the project include Exxon, General Electric, Northeast Utilities, Empire State Electric Energy Research Corp., and the New York State Energy Research & Development Authority. In addition, a $15 million contract is being negotiated with the Energy Research & Development Administration. Omega X simultaneously will direct very short pulses of 24 laser beams from at least 12 directions toward spherical fuel pellets containing deuterium and tritium. The converging beams will heat and greatly compress the pellets, igniting fusion to form helium nuclei and releasing energy. Omega X will have a peak power of 20 to 40 terawatts (trillion watts), estimates Dr. Moshe Lubin, laboratory director. This is double the expected power of a "second genera-
Rochester's laser fusion system focuses 24 beams, two in each of 12 directions, on target (right in cutaway model)
tion," 20-beam system now under construction at Lawrence Livermore Laboratory, and exceeds the entire world's generating capacity, he points out. At Rochester, energy will be stored up and fired in pulses of 0.1 to 1 nanosecond. Lubin expects the system to start operating in about two and a half years, followed by a similar period of intensive experimentation. The object, he explains, is to go beyond the "breakeven point"—where fusion energy released equals laser energy input—and to determine scaling (how much output can be increased with increments of input energy). The Rochester center, founded in 1970, is the U.S.'s only universitybased laser fusion laboratory. (Government labs—at Livermore and Los Alamos—and a private firm, KMS Fusion Inc., are also in the field.) It is also the only center available to outside scientists. Indeed, more than 75% of Omega X's beam time already has been reserved for experiments by scientists around the country, before the new system has even been built. D
Carcinogen guidelines nearly ready from NCI The National Cancer Institute's guidelines for evaluating the carcinogenicity of environmental chemicals are being worked into final form. A subcommittee of NCI's advisory board, working on the guidelines since last September, will present its final version to the full advisory board next week. Further changes are possible from both the subcommittee and the advisory board, but the essence of the carcinogenicity guidelines likely will remain intact. NCI's guidelines are based more closely on what can actually be proven in scientific experiments than are March 15, 1976 C&EN
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