NCJ Number
73777
Journal
FBI Law Enforcement Bulletin Volume: 49 Issue: 11 Dated: (November 1980) Pages: 16-19
Date Published
1980
Length
4 pages
Annotation
A technique for obtaining saliva samples from bitemark evidence is described, focusing on the proper use of the saliva collection kit.
Abstract
Bitemarks are most frequently found in violent crimes, especially in those that involve sexual assaults. Saliva samples can provide information on the assailant's blood type, secretor status, and on the presence or absence of salivary amylase and other proteins. A saliva collection kit should include a control and a sample tube, each containing eight 12-15 mm cotton threads which have been obtained from rinsed sheeting. The vials should have a 2-3 mm hole melted in their plastic stoppers to allow the threads to air dry after they have been moistened in the swabbing process. The kit also should include 3 mm filter paper, a labeled container for a 5cm3 blood specimen, a squeeze bottle for physiological saline solution, a pair of forceps, two double Swube disposable applicators, and a cardboard box containing a 3 cm square piece of rinsed cotton cloth. The forceps are used to handle the cotton thread, which is saturated with saline and then shaken to remove the excess solution. A control sample is obtained by swabbing a 1 by 1 inch area adjacent to the bitemark but not part of it. The second set of threads is used in the same way to secure a saliva sample from within the bitemark ring. The Swube applicators are then saturated with saline, and excess solution is removed by touching them against the filter paper. A control sample and a bitemark sample are also taken to obtain more material for blood typing and amylase testing. Whole blood and saliva standards are also taken from the victim to facilitate an interpretation of the blood grouping tests. The cotton cloth in the box may be used to secure the saliva sample from the buccal mucosa, directly opposite the molar teeth on one side. The blood sample is obtained in an appropriate manner. Specimens should be transported to the laboratory as soon as possible. Storage at 4 degrees centigrade is also acceptable. Photographs and footnotes are included.