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Figure 3. HPLC separation of barbiturates on HI-EFF Micropart Silica Gel Column. Compounds: (1) hembarbital, (2) secobarbital, (3) aprabarbitai. (4) phenobarbital. Figure courtesy of Applied Science Labs.
Figure 2. Separation of cocaine, heroin, methadone, and their metabolites. Compounds: (1) ecgonine HCI. (2) secondary methadone metabolite HCI. (3) primary methadone metabolite HI. (4) methadone HCI, (5) cocaine HCI, (6) benroylecgonine.4H20, (7) morphine. (8) EOacetylmorphine HCI, (9) 3 , M i O-acetyimorphine. Derivatired with N.0-bis (himethylsilyi) acetamide. 10% OV-101 on 100/120 mesh Gas-Chrom (I.Courtesy of Applied Science Laboratories.
The recent developments in two areas are worth notinp. First, theadwnt oicapillars cvltmn GC has allowrd toxicoioaists again to stretch the limits on methods and the size of samples that can he reproducihly detected and measured. Capillary columns are those that use very small bore tubing for a column, with the adsorbent adhering to the sides of the column rather than being packed onto a solid, stable support. In many cases, this allows the substances in the carrier gas to equilibrate more rapidly with the adsorbent, producing a better separation. Second, rapid progress is being made in developing methods for high-pressure liquid chromatography. These methods are becoming so important that HPLC instruments are rapidly achieving the level of importance of other analytical . instruments in the toxicology lahcrrarory. Suhstances as diverse as \,itamins, analgesics, and harhiturarrs are nou, ot'rrn analvzrd In. kIPLC3 iser Fir. 3). This discussion would 6e incomplete if'it did& include the interfacine of instruments of basicallv different tvoes in order to provrde identification techniques far heyoidwhat anv one method could achieve. S~ecificallv.the advent of reiatively inexpensive, reliable, gas chrokatograph/mass spectrometer instruments, coupled with computer interfaces, is providing laboratories with a capability for identification and quantitation that is far beyond what has been available in the past. As an example ofthe wide use of such instruments, readers are undoubtedly familiar with the use of GCIMS methods in drue testine oro~rarnsa t race tracks. for large athletic events, su>h as the Olympics, and for othe; reeulated activities. or reeularlv scheduled oroerams. Bv a computer cfatata library with boih C k and MS data. oatterns of experimental data mav he matched against the library data, to determine the identity and quantity of a given compound. ~
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Blood Alcohol Analysis Newsletter, Supelco. Inc., Bellefonte. PA 16823.1980.
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TIME (Minutes)
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5 10 T i m (Mimes)
An Open Fleld Toxicology is a profession in which both chemistry and biology play a very important role. The toxicologist may be working on a forensic problem, such as the determination of the cause of death. His or her assignment may be to determine the composition of a blood sample in order to prevent death, such as in the case of a drug overdose at a hospital. He or she may be assigned to determine the level of a particular water pollutant thought to be causing significant health problems.
Research Directions in Forensic Chemistry G. F. Sensabaugh Forensic Science Group De~artmentof Biomedical and Environmental HealIi- Sciences ~ c & o lof P L c~ hca tn .,n verslty o l Ca lorn a Berreley CA 94720
The orimarv comoonents of the oractice of forensic science are thr nnalgsis and interprrrntion of phyiical evidence in crim~nalund civil cases. Therefore,it is not surorisinr that forensic science research is also concerned with issues of analvsis and interpretation, The analvtical focus is principall; directed to the development of analytical methodologies that are appropriate, accurate, robust, and reliable in the forensic context. The interpretative concern is expressed in the generation of appropriate background knowledge so that the simificance of analvtical findinps can be under" stood and explained. Research addressing" both concerns has contributed sie" nificantly to the advancement of forensic science over the last decade. and it is clear to all who work in the field that the research effort must continue if the field is to continue to advance. I t is therefore appropriate to ask where forensic science research is headed. I t is also important to ask who is doing forensic science research and how it is supported; the who and the how obviously influence the direction of research in the field.
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Volume 62
Number 12 December 1985
1051
Trends in Forenslc Science Research
The best window on the future is to be gained hy reviewing recent trends in the field. T o this end, three major English language journals (Journal of Forensic Sciences, Journal of the Forensic Science Society, and firensic Science International) were surveyed over the period 1973-82.' Articles with a chemical component were partitioned into four topic categories: hiology (mainly blood and other biological fluids), trace evidence (the broadest category, includes soils, fibers, glass, paint, arson accelerants, explosives, gunshot residues, etc.), toxicology, and pathology (chemistry of death). The survey indicates a substantial expansion in research publication over the period 1972-78; both the article count and the total journal page count nearly doubled in this interval. Since 1978, both indicators show much smaller increases. Trends in forensic research interests are indicated bv the vear-to-year proportion of papers in each of the areas. The p;oportion in t h e toxicolo& and pathology areas remained relatively constant over the 10-year period a t about 31%and lo%, respectively. In contrast, the proportion in the hiology area doubled from 1972 to 1978 (15% to 29%) and since-has dropped to its current level of about 20%. The increase from 1972 to 1978 reflects the impact of a shift in technoloev: in the mid-1970's electronhoresis was increasingly applied to biological evidence problems. The proportion of Daoersin the trace area varied inverselv in relation to the hioioiy share. The maioritv of the articles surveyed were oriented toward analitical as opposed to interpretative concerns. In the biology, trace, and toxicology areas, more than 80% of the articles focused on methodology development. In the pathology area the distribution between analysis and interpretation was about even. However, despite the overall emphasis on methodology, it is clear to workers in the field that methodoloev develooment does not answer internretative auestions and that ihese questions must he facedhead on. ' Where then is forensic science research headed? The following developments can be anticipated. Biology. As new genetic markers are discovered, new techniques of marker analysis will be developed. Monoclonal antibodies will hewme important tools and there may be a resurgence of immunological technologies. More attention will be given to the mechanisms of marker deterioration in evidence material and the quantitative baseline on genetic and tissue markers will expand. Trace Eoidenee. Advances in instrumental approaches will include increased use of HPLC and microprocessor based instrumentation. More attention will he given to the mechanisms of trace evidence generation and to the distribution of trace evidence items
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A more complete analysis of this survey is to appear in the ACS symposium series volume Forensic Science, 2nd ed. Peterson, J. L.. Mihajlovic, S., andBedrosian. J. L.. "The Capabilities. Uses, and Effects of the Nation's Criminalistics Laboratories," J. Forens. Sci., 30, 10 (1985). Personal communications: M. Hoffman (ATF),B. Brown (FBI),and S. Sobel (DEA).
1052
Journal of Chemical Education
in the environment. The development and use of computerized databases will expand. Toxicology. Instrumental approaches will expand with increased emphasis on computerized search-identification interfaces. The concern with environmental toxic agents will increase. There will be more studies on the mechanisms of chemical toxicity and on idiosyncratic variation in drug response. Pathology. Post-mortemchemical changes andchemical changes associated with woundine These " will continue to he investieated. " may lead to new approaches to assessing the cause and time of death.
Who Does Forenslc Science Research and How Is It Supported?
The journal survey showed the author affiliations for papers originating from the U S . in the period 1978-82 (266 ~ a ~ e rtso )be distributed as follows: state and local level torensic lahoratories; 48%; academic institutions, 40%; industrv, 8%: and federal level laboratories. 4%. This distrihution showsthat nearly half the forensic research effort originntes from workinc crime lahoratories. Thin effort is partto time; on the average, about 5%of laboratory time is research a ~ t i v i t i e sFull-time .~ forensic research occurs only a t the federal level; between the F.B.I. and the D.E.A. there are approximately 20 designated research positions.3 The academic contribution is higher than might be expected given that there are very few academic programs in forensic science and that there is no mant suoDort . . Droeram . .. designated specifically lor forensic research. The distribution of the forensic science research effort in other countries differs from that in the U S . Most forensic research in Great Britain originates from the Home Office Central Research Establishment laboratory or the research division of the London Metropolitan Police (Scotland Yard); these two lahoratories are staffed with about 50 dedicated research scientists. On the Continent, in contrast, most forensic research is of academic oriein: manv state-sunnorted universities in Europe have depa&ents bf legal medicine. In Japan, forensic research isdone both in university departments of legal medicine and a t the National Research Institute of Police Science; the latter has a scientific staff exceeding 30. Thus inBritain, Europe, and Japan, forensic research is done in the context of established research support structures. Conclusion
The importance of expanding the research base in forensic science is-recognized h i everybody in the field; research is, after all, an investment in the future. The needs of the field are real and the notential for nroeress is ereat. However. progress in the U.S. is likely t o bk sl& due i i p a r t to the lack of any organized support structure. I t is ironic that a country that so prides itself on the quality of its justice system does so little to support services such as forensic science which directly improve the quality of legal decision making.
