50th SEMI-ANNUAL SEMINAR (Fall 1977)
CALIFORNIA ASSOCIATION OF CRIMINALISTS
October 13-15, 1977
San Jose, California
NINHYDRIN: A COLOR TEST FOR THE DIFFERENTIATION OF PHENETHYLAMINES
J. D. Beede, P. J. Cashman and J. I. Thornton
Chemical analysis in the form of color testing has long been employed in the forensic analysis of restricted dangerous drugs and narcotics. Although not specific per se, these reactions impart a certain amount of insight with respect to the particular compound being tested. This is especially evident in the case of reagents exhibiting variable colors with different classes of compounds. Unfortunately, the color reagents themselves are usually limited to producing a given color with a particular class of compounds.
This study proposes to introduce the ninhydrin reagent as a color test which exhibits a high degree of intra-class specificity for the phenethylamines. It is well known that ninhydrin in certain solvents will react differentially with primary and secondary amines to produce colors that range across the visible spectrum. In the case of phenethylamines such as amphetamine, methamphetamine, STP and mescaline, the reagent displays various colors that are easily discernible. The reaction is at once fast, easy to perform, and is capable of detecting microgram amounts of material. In conjunction with the other color reagents commonly in use, the ninhydrin reaction will provide the analyst with more explicit information regarding the probable nature of the phenethylamines of forensic interest.
DENSITY AND ABSORBANCE AS COMPARATIVE PROPERTIES IN GASOLINE THEFTS
In the refining of gasoline the density of the resultant product varies within certain limits. Seasonal modifications in the fuel's composition also affect density at the time of production. Distribution procedures and storage conditions subsequent to the refining and piping of gasolines to a distribution facility further alter the fuel's properties.
In this study the densities of over 250 samples of automotive gasolines were measured. In one portion of this project the changes in density and visible dye spectra with time were plotted over a five-month period for a single gas station, while in another, 60 samples were collected locally on a single weekend with particular attention focused on the results for those gasoline samples of the same grade and brand, but from different stations.
PHASE CONTRAST MICROSCOPY VS. DIFFERENTIAL INTERFERENCE CONTRAST MICROSCOPY AS APPLICABLE TO THE OBSERVATION OF SPERMATOZOA
G. B. Cortner and A. J. Boudreau
This paper explores the use of phase contrast microscopy and different interference contrast microscopy and different interference contrast microscopy for the observation of spermatozoa. Comparisons have been made utilizing both types of microscopy on human spermatozoa as well as several species of animals in an effort to demonstrate the pros and cons of each technique.
FIREARMS SAFETY SYSTEMS AND ACCIDENTAL DISCHARGES
J. B. Bolenbach
A discussion of accidental shootings as they relate to safety systems employed in commonly encountered weapons.
RECENT TRENDS IN FIREARMS AND AMMUNITION MANUFACTURE
J. B. Bolenbach
A discussion of modern weapons systems, their identification and operation, with a review of recently introduced ammunition components.
REVIEW OF LAMP FILAMENT EXAMINATION
L. W. Bradford
A review of the technology of lamp filament examination and the application of such evidence to forensic science problems.
PLANS FOR IMPLEMENTING REGULAR PROFICIENCY TESTING OF LABORATORIES LICENSED FOF FORENSIC ALCOHOL ANALYSIS
D. R. Morales
Provisions in the Health and Safety Code assign to the Department of Health responsibility to "insure the competence of such laboratories and employees to prepare, analyze, and report the results of such tests," referring to forensic alcohol analysis. The California Administrative Code (Title 17) contains regulations which the Department of Health uses to administer this responsibility.
Among the principal elements in the regulations are the following: written method descriptions, on-site inspections, and proficiency testing. With the adoption in late 1975 of amendments clarifying the regulations, the Department of Health worked with the licensed laboratories during 1976 to guide them in filing method descriptions which clearly demonstrated their abilities to meet the requirements of the regulations. During early 1977, the emphasis shifted to on-site inspections, whose goal is to corroborate that laboratories' operations are consistent with their filed written descriptions. Now, emphasis has shifted to a program of regular proficiency testing of laboratories. This presentation will describe and explain the Department of Health's plan for implementing regular proficiency testing.
APPLICATION OF DIFFERENTIAL INTERFERENCE CONTRAST MICROSCOPY TO THE EXAMINATION OF PAINTS
A. J. Boudreau
This paper relates the observed benefits of Incident-Polarized and Differential Interference Contrast microscopic techniques applied to the examination of paint specimens.
RECONSTRUCTION OF BROKEN GLASS BY MEANS OF REFLECTION INTERFERENCE FIGURES
J. I. Thornton and P. J. Cashman
Using the Argon gas laser with a beam dissipator, it is possible to project an interference figure of a glass surface onto a plane surface. This interference figure may be due to either compositional heterogeneity, or lack of uniform thickness, or both. The interference phenomenon observed is independent of stress, and persists after the glass is broken. Consequently, the continuity of the interference fringes may assist the criminalist in the orientation of fragments of broken glass, and in some instances will confirm a physical match of the fracture edge.
PREPARATION OF LECTURE SLIDES
D. Q. Burd
To be a competent criminalist you must have basic photographic (normal, macro and micro) knowledge and ability. While many have such knowledge, it frequently seems to be forgotten when slides are prepared to illustrate lectures and paper presentations. This talk will illustrate errors frequently observed and give suggestions and illustrations regarding proper and effective slide preparation.
THE EFFECTIVENESS OF ACID PHOSPHATASE DETERMINATIONS BY ACRYLAMIDE ELECTROPHORESIS IN SEX OFFENSE CASES
K. E. Inman
Acrylamide electrophoretic determination of seminal and vaginal acid phosphatases in sex offense cases has been evaluated in this laboratory. The genetic basis for this test will be reviewed, and some anomalous results will be presented. In roughly 25% of the total cases examined, the electrophoretic determination of the origin of the acid phosphatase activity is the definitive test in the analysis. The anomalous results (mainly in the form of a band intermediate to the seminal and vaginal isozymes) require great caution in hasty interpretations of high levels of enzyme in the absence of sperm and precludes use of the test as a panacea.
UNEXTRACTED BODY FLUID RADIOIMMUNE ASSAY FOR Δ9-THC VALIDATED BY A NON-IMMUNE TECHNIQUE
Stanley J. Gross, M. D. and James R. Scares, Ph.D.
Radioimmune assays are being increasingly used to quantitate small molecules in body fluids because of accuracy, precision and ease for numerous samples. Improvements in technique continue to be made 17 years after introduction. The use of superior immunogens to elicit specific antisera has recently received much attention and has elevated RIA precision to that of the most advanced analytic techniques.
Carefully planned cannabinoid derivatives were used for immunogen syntheses. The resultant antisera allowed development of a specific direct body fluid assay discretely for Δ9-THC. Each metabolite could be studied separately by similar methods.
Numerous body fluid samples (blood, urine and saliva) following drug administration were monitored over a time course. Native Δ9-THC concentrations were compared to that of the carboxy metabolite.
Radioimmune assays were thought likely never to be validated by rigorous analytic methods because of specificity and reliability problems. Split serum samples in our Δ9 -TCH radioimmune assay and by quantities GC-mass spectroscopy performed elsewhere correlated well. (Corr. Coef. 0.87)