Document 6RV6X6yonzGJ3dERrqz8Domjg

Science URL 04781 chemical to one group member--for example, a pesticide to a specialist in that area. This scientist reviews and critiques the available material and supplements it from his or her own knowledge and literature search, and then brings all the information to a quarterly meeting for a group evaluation and consensus. "It's a real labor of love and dedication," Kissman emphasizes. Until now, he points out, the group members have reached their conclu sions by meeting around a large table, with the necessary huge stacks of documents spread out in front of them. However, the TDB managers hope to move this process into a new era within the next year or two. They are working with Lister Hill National Center for Biomedical Communica tions (the R&D arm of NLM) to ex plore applying an on-line computer to the peer-review process. This "com puterized conferencing procedure" would involve members of the group entering statements on compute* terminals at their university offices. Other members could see and com ment on the statements, until a con sensus was reached by a Delphi pro cess. Such a method would be adapt able for other committee-produced documents, such as criteria docu ments for occupational health and safety regulation. Information in TDB is organized around each chemical, with records containing about 60 different data elements. These include chemical, physical, biological, pharmacological, toxicological, occupational, and en vironmental information, and man ufacturing data. Original literature references also are given for all data. The toxicological data include carcinogenicity, mutagenicity (in cluding genetic-toxicology program summary statements), and teratoge nicity. The manufacturing data in clude synthetic methods, natural oc currence, patents, production and distribution information, applica tions, purity assays, and regulatory status. Information on manufactur ers, U.S. production figures, U.S. imports and exports, consumption patterns, major uses, and methods of manufacture are provided under contract by SRI International. TDB is one of 18 on-line, interac YEARS OF SERVICE to the chemical industry. Quality. Service, and Economy for all chemicals. It's a basic principle of our company. Your continued patronage has proven this approach to be successful. Chemicals tor Research, Development end Production In appreciation, we thank you, Our Customers /^2"`>xChefn*cal Dynamics Co^p- (55 ar ) 300' Hactav *o PO Bo i 39b South Nj 070B0 , 201/7S3-SOOO Tttea B33-44? CRCL 48 ON READER SERVICE CARD 14 CAEN Oct IS, 1982 tive information retrieval services available through NLM's MEDLARS system (Medical Literature Analysis & Retrieval System), with terminals at some 1500 institutions and regional medical libraries connected to NLM's computers. Among the other systems are MEDLINE (with some 600,000 references to biomedical journal ar ticles from the past three years), TOXLINE (a collection of 500,000 references from the past five years on toxicity studies), and CHEMLINE (a chemical dictionary tile with de scriptions for more than 500,000 chemical substances). . TDB is readily accessible to users, with payment of only a few dollars at the most required for complete in formation on a compound. (TDB costs $22 an hour for on-line use at Srime time, $15 for nonprime time.) 'sers often ask to have data printouts mailed to them off-line at 15 cents a page, further reducing the cost. Spann notes that during a recent six-month period, about 46% of the users were from industry, 27% from ,, nonuniversity research institutions and government, 12% from medical schools, 7% from hospitals and clinics, and the remaining 8% from other sources. In 1980 there were an esti mated 43,000 searches. Selected information can be ex tracted according to user criteria. For instance, an insurance company can ask for toxicological data on a drug in response to a legal suit; a researcher can request data on the carcinogenic effects of toluene on white males in the U.S. TDB's data come mainly from tertiary literature sources--that is, from monographs, reviews, hand books, textbooks, and criteria docu ments. This is supplemented by primary literature articles (re search papers from journals) sug gested by reviewers, and secondary sources such as Chemical Abstracts. The advantage, Kissman points out, is that tertiary sources already have undergone a filtering process. One disadvantage, however, is that it takes a relatively long time for infor mation to make its way into the ter tiary literature. Therefore, the TDB review com mittee is making an effort to incor porate more primary sources, partic ularly because TDB has been criticized for not having the most up-to-date information. Only pub lished literature sources are used, with the addition of manufacturing and economic data from SRI. Indeed, updating data already in the system is a growing priority. Sys- Data bank lists comprehensive data for each chemical Substance Identification Chemical name Toxicology Data Bank number Chemical Abstracts Service Registry Number Synonyms Molecular formula Molecular weight Wiswesser Line Notation Substance classification Chemical class Major uses Chemical/physical properties Melting point Boiling point Density/specilic gravity Vapor pressure Flashpoint Color/form Stability/shelf life Spectral and other properties Solubility Toxicological effects Animal/nonhuman studies Human studies Toxicity values Minimum fatal dose Maximum daily intake LD values (lethal dose) Laborstory analytical methods Interactions in biological systems Pharmacology Metabolism Absorption, distribution, excretion Pharmacodynamics Pharmacokinetics Pharmacotherapy Therapeutic use Cautions Mechanism of action Tolerance and resistance idiosyncrasies, rmprsibifity Antidotes and emergency treatment Manufacturing information Manufacturers Methods of manufacturing U.S. production U.S. Imports U.S. exports Consumption patterns Shipment methods Environmental and occupational data Explosive limits Fire potential Poisoning potential Radiation limits and potential hazard Disposal methods Pollution potential Exposure limits Threshold limit value Environmental accumulation, degrada tion, and persistence tematic quarterly updating of the oldest group of chemicals is being done, and 682 chemicals already have been updated. In addition, publica tion of new editions of handbooks and other sources is monitored. Initially, TDB was not available to foreign countries. But in the past year, Canada, West Germany, and Australia have established access to the file. Other countries have indi cated an interest, and further ex pansion abroad is anticipated. There are, of course, other toxico logical data systems in the U.S. and abroad, Kissman notes. The National Institute of Occupational Safety & Health (NIOSH) for instance, has some 54,000 chemicals in its Registry of Toxic Effects of Chemical Sub stances (RTECS). However, the NIOSH and TDB systems are dif ferent in breadth and scope: NIOSH's system offers a large number of com pounds but relatively little informa tion on each; TDB, by contrast, covers relatively few compounds but has a great deal of information on each. Indeed, the major RTECS data cat egory is just one of many categories in the TDB file. RTECS also has no peer-review system. There also Is an International Register of Potentially Toxic Chem icals (IRPTC) that recently started up (C&EN, May 10, page 25), cov ering 330 chemicals so far. TDB col laborates with IRPTC, and Kissman notes that its data are even more de tailed than TDB's. However, he points out, IRPTC is not computer accessible, but only available through hard copy. Besides working on a computer conferencing procedure for peer re view, the TDB managers also hope to go to a more "user-friendly" system. For example, Kissman hopes it will be possible to improve access by moving to use of minicomputers in the next year or two. Furthermore, he points out, the software currently used is that for general use in the MEDLARS system. It was not de signed for data delivery, but rather for massive bibliographic files, and so it has problems in handlingthe60 or more data elements in TDB. Hence, TDB will move in 1983 to more ap propriate software. CKX 36 ON READER SERVICE CARD Oct. 18, 1982 C&EN W URL 04782