Dr. Kataoka explains, is inherent in cuprammonium rayon. The result in practice is that dosage of heparin—an anticoagulant used during treatment to minimize clotting problems in the machine—can be reduced, and less blood remains in the device after use. The commercial product being made by Asahi is a cylindrical dialysis unit, 2.75 inches in diameter and just under
Asahi claims its dialysis unit is more efficient than U.S. hollow-fiber device 10 inches long. Resembling a small shell-and-tube heat exchanger, the device contains 8000 hollow fibers within a shell of acrylic/styrene copolymer and polypropylene. Effective dialysis surface totals 1.1 sq. meters. Bloodside pressure drop is about 10 mm. Hg, so blood circulation through the device generally requires no pump. In Japan the price of the Asahi throw-away dialyzer, set by the Ministry of Health and Welfare and charged by hospitals, is about $47. This cost generally is paid by Japan's national health insurance system, rather than directly by the patient. The Cordis Dow dialyzer sells for the same price in Japan, but in the U.S. it sells for an average of about $20 per unit. Currently, treatment schedules with the devices are the same as with other artificial kidneys, typically a five- to six-hour dialysis, three times a week. Shortening the treatment time is Asahi's next development goal. There's a limit to enlarging dialysis area, Dr. Kataoka points opt-, since the quantity of blood that safely can be outside a patient's body at a given moment is small—about 200 cc. for an average adult. Clinical testing so far shows that
two Asahi devices in tandem (each has a bloodside volume of about 100 cc.) can cut dialysis time per treatment to three or four hours. In the U.S., Cordis Dow sells a single, larger unit that can do the same, the Cordis CDAK 5. Another Asahi approach to speeding up dialysis relies on the high strength of cuprammonium hollow fiber—three to five times that of triacetate, according to Asahi data. This may open the way to thinner fiber walls or use of dialysate-side turbulence to improve transfer rates. Meanwhile, Asahi has started up a 36,000 unit-a-year production line at Oita. Planning to concentrate first on domestic sales, the company is building a new facility at the same location that will raise capacity 10-fold when completed in August 1975. At an assumed demand of about 100 dialyzers per patient a year, Japan's Science and Technology Agency estimates potential demand for disposable devices at 2.3 million a year in Japan, about 100 million worldwide. Cordis Dow's Dr. Murphy, although reluctant to discuss the volume of the company's U.S. business, says it's growing steadily. Though Asahi and Cordis Dow are now alone in the hollow-fiber dialysis market, at least one other entry is in the wings. Boston-based Amicon Corp., a maker of surgical fibers, currently has a polysulfone hollow-fiber dialyzer in clinical trials. According to Michael J. Lysaght, director of research for Amicon, the company expects to bring it to market in about two years. Advantages of the Amicon unit, Mr. Lysaght says, are a high clearance rate (similar to dialysance) for middle-molecular-weight molecules, and the fact that it can be shipped dry, unlike the Cordis Dow and Asahi units, which must be shipped with formalin.
Caution urged on more ocean oil drilling Government policy decisions must be made in the near future about such controversial energy-related issues as expansion of offshore oil drilling, construction of coastal refineries, and building of oil tanker "superports." However, these decisions will have to be made "in considerable ignorance and uncertainty" and with "large knowledge gaps and conflicting opinions" about their ecological impact, according to a report, "Oil Spills and the Marine Environment," just released by the Ford Foundation's Energy Policy Project, Washington, D.C. Indeed, the report says, "Because so many serious questions remain unanswered, and because of the alarming implications of some of the information available, we recommend great caution in making policy decisions involving oil and the marine environment."
Furthermore, S. David Freeman, director of the Energy Policy Project, tells C&EN that the state of knowledge of oil behavior and control indicated in the report raises grave doubts about multiplying tanker traffic and expanding ocean oil drilling. For example, he is "leery" of starting oil drilling now proposed in the Atlantic Ocean off the U.S. East Coast and in the Gulf of Alaska. "We don't know enough on the environmental effects and resources base to go ahead," he says. Instead, Mr. Freeman advocates that the U.S. concentrate in the next few years on energy conservation to slow down rising oil consumption. "Through conservation measures," he says, "we can buy a few years' time so that we can plan development, find offshore drilling sites that are acceptable," learn more about the effects of oil spills, and develop better control methods. "We should not drill before we know the full impact on ecology." The 130-page report is in two parts. The first part was written by Dr. Donald F. Boesch and Carl H. Hershner, marine biologists at the University of Virginia. It gives an overview of current knowledge of the effects of oil pollution on marine life. The second part, prepared by Dr. Jerome H. Milgram of the department of ocean engineering at Massachusetts Institute of Technology, surveys current technology for oil spill prevention, control, and cleanup. Dr. Boesch and Mr. Hershner note that oil pollution research to date has had serious limitations. For instance, postaccident studies often suffer from lack of planning, nonquantitative observations, and too little baseline information for comparison. On the other hand, experimental studies—exposing selected species under controlled lab (bioassay) or field conditions to oil or oil dispersants—may give results irrelevant to the real world. And observations of oil spills have most frequently concentrated only on gross or catastrophic effects, whereas chromatographic and spectroscopic chemical analysis should be used to trace longterm, chronic, and sublethal effects. They cite, for example, suggestions that low levels of oil hydrocarbons may disrupt photosynthesis, respiration, and other metabolic functions and disturb feeding, reproduction, and chemoreception ("smell") in marine organisms. Among the conclusions of the two Virginia biologists are several relating to human health, touching points now under dispute in a National Academy of Sciences committee that is preparing a report on the fate and effects of petroleum in the marine environment (C&EN, June 10, page 16). For instance, Dr. Boesch and Mr. Hershner conclude that absence of an oily odor or taste in seafood does not guarantee its safety for human consumption. Odor or taste is "not a definitive test for contamination," they say, "because July 15, 1974 C&EN
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the odorous or distasteful portion of the petroleum may be shed while other contaminants are retained." On another point, it has been suggested that hydrocarbons ingested by lower marine organisms may be concentrated through "biological magnification'' in going up the food chain and lead to high concentrations of possibly carcinogenic hydrocarbons in seafood eaten by man. However, Dr. Boesch and Mr. Hershner say, "there is at present no convincing evidence of food chain magnification of petroleum hydrocarbons." Furthermore, the Virginia duo finds, there is evidence that shellfish and fish that have accumulated hydrocarbons from sea water will shed them and cleanse themselves "rapidly" (within a few months or less), if maintained in uncontaminated sea water. On the overall threat of cancer being induced in man from eating oil-contaminated seafood, Dr. Boesch and Mr. Hershner cite the "conservative view": The amount of potential carcinogens in seafood may be small compared to that in green vegetables, roast meat, and other food, but "there is no lower threshold of carcinogens in the body" and "any increases should be avoided." The two scientists mince no words in stressing the need for more intensive and better financed research, particu-
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C&EN July 15, 1974
LC unit automates gradient system
larly on chronic and sublethal effects. "Research sponsors, seeking quicker and more tangible results from their investments, have often preferred to fund symposia to look into the prob- "First-Run LC" is the term coined by lems rather than underwrite lengthy Philips Electronic Instruments, Mount and expensive research," they assert. Vernon, N.Y., to describe the capabiliFederal funding has been "grossly defi- ties of its new liquid chromatography cient." And scientists, too, are to package, which combines Philips' Pye blame; "their reluctance to address the Unicam LCM2 liquid chromatograph problem is at least in part due to the with the Anasol-20 Solvent Program great length of time required for re- System, made by Analabs, Inc., North search on the effects of oil, which pre- Haven, Conn. Anasol-20 makes possicludes immediate rewards of publisha- ble automated incremental gradient elutions using procedures developed by ble results." Similar small progress—in devel- Dr. R. P. W. Scott of Hoffmann-La oping technology for controlling and Roche, Inc., Nutley, N.J. removing oil spills—is described by Dr. According to Philips, the system enMilgram in his part of the report. He ables programing of a continuous granotes the severe limits of current dient covering the polarity range from equipment and materials, and points heptane to water in small increments. out that oil spill control is one of the Everything in the column can be de"most difficult and most misunder- tected with no sacrifice in resolution, stood problems in ocean engineering. Philips says, and, since the method reImproved spill prevention and control veals significant information on the will be expensive," he emphasizes, and first run, unknowns can be "scouted" R&D in this area has not received suf- in hours instead of days. ficient support. The Anasol-20 consists of the proDr. Milgram relates an anecdote il- gramer unit, a 20-position motor-drivlustrating the problems. "Asked for his en Teflon rotary valve, solvent reserhonest recommendation for dealing voirs and rack, and a concentration with a large spill at sea, a former tank- profile modulator. The system, without er captain from one oil company said, pump, sells for about $4400. The programer unit is a digital timT h e best thing you can do is uncork ing instrument storing 16 numbers of another bottle of whiskey! ' " two digits each in an integrated circuit memory. The program to be stored is Bubble memory entered manually by means of a front the smallest panel thumbwheel switch and a memory store button. The 20-port rotary yet developed valve is automatically controlled for Technology employing the programed times, for the first 16 magnetic bubbles—minute, positions. The last four positions are magnetized areas formed in for solvents to recondition the chromathin films—keeps pushing tographic column between analyses. toward smaller and smaller Thus, the system can handle as many devices. Here, Bell as 20 solvents, with programed elution Telephone Laboratories times ranging from one to 99 minutes scientist Paul C. Michaelis per solvent, for total runs of up to 33 examines a new mass hours. In actual separations on silica bubble memory designed for gel columns, however, 12 solvents ranguse in telephone switching ing in polarity from n-heptane to water systems. The smallest yet have been found sufficient to cover the developed, it can store the solute polarity range evenly. Information equivalent of The LCM2 is a good companion for 27,000 telephone numbers. the Anasol-20 because of its moving• wire/flame ionization detector. The eluate, deposited on an oxide-coated stainless steel wire, is first oxidized to carbon dioxide and then catalytically reduced to methane, which is measured by flame ionization. Dr. Scott notes that UV detectors aren't suitable with the gradient elution technique, because all the intermediate-polarity solvents absorb strongly in the UV region. With the LCM2's detector, the solvent evaporates before detection and therefore doesn't interfere with detection. Philips adds that many compounds of interest are transparent to UV but can be detected easily with the flame ionization detector when their carbon component has been converted to methane.
