Emphasis grows on clinical pharmacology, toxicology Growing concern about man's chemical relation to his environment was underscored last week by the proportion of papers devoted to clinical pharmacology and toxicology presented at the 19th annual meeting of the American Association of Clinical Chemists, in Philadelphia. About 107* of the 86 contributed papers told of research in bioanalytical methodology, aimed at finding rapid, specific, and sensitive tests for various exogenous chemicals harmful or beneficial to man. While there is a degree of overlap between the realms of toxicology and pharmacology, the basic aim of the pharmacologist is to maximize therapeutic effects of drugs while minimizing their toxic effects. The toxicologist is concerned with the harmful effects of all exogenous chemicals. The scope of clinical toxicology ranges from the cloak-and-dagger aspects of forensic toxicology (C&EN, Aug. 14, page 48) to the workaday social problems of water and air pollution, the dangers of pesticides, the increasing misuse of drugs, and the like. Dr. Fred Rieders of the medical examiner's office in Philadelphia told of the mounting demands on toxicologists for routine social services, such as "drunkometer" tests, and lead, aspirin, and barbiturate determinations in accidental or suicidal poisonings. These demands have caused increasing use of sophisticated instrumentation resulting in a "widening gap between elucidation of chemical reactions and utilization of this knowledge for systematic analytic methodology," he said. He pointed out, however, that equipment costs, burdens of maintaining skills for procedures required only intermittently, and the cost (in time) of changing the operating mode of instruments are beginning to press for balance between classical chemical methods and sophisticated instrumentation. As an example of this balancing trend, Dr. Rieders disclosed an inexpensive, rapid, sensitive, wet-chemical method for. analysis of toxicologically important anions. It was developed by Dr. Carlos Alberto Garcia of the University of Littoral, Rosario, Argentina, in cooperation with Dr. Rieders. The method uses a sequence of separation by microdiffusion and detection and identification by thin-layer chromatography. Cyanide and bromide can be detected in parts-per-billion concentrations. Other anions, such as bromate, borate, fluoride, chlorate, thiocyanate, salicylate, and phenolate, can be determined in parts per 32 C&EN AUG. 28, 1967
million. Dr. Rieders calls the method "the jungle method" because "you can practically carry the required equipment around in your pocket." In addition to the Rieders-Garcia work, some pharmacological results of note were disclosed at the week-long meeting: • Identification of antihypertensive drugs such as thiazides and rauwolfia alkaloids in urine, by Algird V. Gudaitis and Dr. Robert M. Donauer of Prudential Insurance Co. research laboratories, Newark, N.J. The methods utilize column and thin-layer chromatography. • A rapid, improved method for determining the soporific Doriden in the blood, by Marjorie Knowlton and Dr. Leo R. Goldbaum of Walter Reed Army Institute of Research and the Armed Forces Institute of Pathology, Washington, D.C. The determination uses methylene chloride and can be done in less than an hour. • A semiquantitative thin-layer chromatographic method of determining anticonvulsant drugs in blood and urine, by C. E. Pippenger, J. E. Scott, and Dr. H. W. Gillen of New Castle (Ind.) State Hospital and Indiana University Medical Center, Indianapolis; 174 commonly used drugs were studied. • Studies of the protein binding of acetylsalicylic and salicylic acids and their separation by gel filtration, by M. Amir Ali and Dr. J. I. Routh of the University of Iowa, Iowa City. • A rapid method for estimating ethanol in body fluids, by Dr. Donald W. Jones, Dr. Louis P. Gerber, and Dr. William Drell of Calbiochem Corp., Los Angeles, Calif.
Beckman to market units for water pollution control Instruments designed for the water pollution control market are about to be marketed by Beckman. The total organic carbon (TOC) analyzer, which will be shown at the ISA meeting in Chicago next month, is the first commercial instrument of its type in the field, Beckman says. The second one, the water quality monitor, combines eight instruments into one chassis for continuously monitoring streams and effluents. Its first appearance will be at the meeting of the Water Pollution Control Federation in New York City in October. The concentration of organic materials in water is of paramount importance to pollution control. Standard methods of measuring organic carbon have been to determine either biological oxygen demand (BOD), which takes about five days, or chemical oxy-
Total organic carbon analyzer Carbon standard a potential assist
gen demand (COD), a procedure that takes about eight hours. There are relationships between organic carbon and BOD or COD. These methods are much too slow for the great number of determinations needed today. Several years ago, scientists at Dow Chemical developed a procedure for total carbon in water. They passed a sample over a catalyst in a high-temperature furnace and measured the resulting carbon dioxide with an infrared analyzer. Beckman licensed the patented method and marketed its carbonaceous analyzer three and a half years ago. While the instrument could do an analysis in about two minutes, it had the disadvantage of measuring carbon from carbonates and dissolved carbon dioxide as well. The new TOC is based on a modification of this procedure by Dr. C. E. van Hall and Dr. V. A. Stenger of Dow; it too is being made under a license from Dow. The instrument has two channels for injecting the sample. One, as in the original instrument, passes through a high-temperature (950° C.) furnace and measures total carbon. The second channel passes through a low-temperature (150 c C.) furnace and measures carbon from carbonates and dissolved carbon dioxide. The carbon dioxide from each channel is determined, in turn, by a single air analyzer. The difference in the peak heights is a measure of organic carbon. At about $5700 for the package—furnaces, air analyzer, and recorder—the instrument is priced $100 below the earlier carbonaceous analyzer. Sales will certainly be helped along by a standard for carbon in water; such a standard is in the offing. Last June, ASTM's D-19 Committee tentatively approved a method for analyzing total and organic carbon by com-
