The Study Of The Credibility On The Human Body Odor Identified By The Canine

The human odor is the basis of the canine tracking and scent identification, which has the biological information. For a long time China had made a lot of research on the training and using of the police dogs, but how to collect more odors without undermine the premise of the evidence ,which left by the crime, whether the identify results credible or as evidence in court, and whether the instrument can identify different individuals had few studies at home and abroad. So this experiment studied with several aspects.1. The odors were extracted by 70μm CW—DVB and analyzed by GC, which were collected by the NJ-1 Scent Collection Tool and absorbed directly with gauze. The chromatographic fingerprint was analyzed by the Paired-Samples T Test and the Similarity Evaluation System for Chromatographic Fingerprint ,the result was P=0.281 and the similarity upon 91%.It implied that the data did not discrepant prominently .So the Scent Collection Tool and the method of absorbed directly could be used to collecting human odor. Analyzed the eight strong peaks and their peak areas, we found that distilled human odor 6 minutes with the Scent Collection Tool and absorbed directly 30 minutes had the same effect ,and even the former had a full impact on main peaks .2. The human body odor was identified with five differential German shepherd which got through examinations by using the method of "Matching-Non-Matching". The results showed that the rate of average identification success was 83.2% within 5-25℃temperature range by the canine and the difference was not significant with the variance analysis. The identification success rate was as more as 82 percent within 6h odor by analysing the delay different times of the odor, which higher than the credibility of the outcome of the identification of national courts .3. The odors from human armpit were analyzed by gas chromatography-mass spectrometry with the head space solid phasd microextraction (SPME) . By calculating the relative retention times of certain peaks with Heptadecane as the reference standard and analyzing the chromatogram, eight strong peaks in the samples were analyzed. A new method was builded which can discriminate different people, by analyzing the eight strong peaks and the similarity of divisional fingerprint chromatogram. Moreover, this method can full-scale reflect the special peaks and the total information of human scent, and first discuss using GC/MS to discriminate different individual.