Primary Study On Discrimination Of Human Body Odors By Police Dog

Human odor is one kind of human body bio-information. Everybody has its own odor character, by which individual people can be identified. The trained police dog has ability to differentiate different people by discrimination of different odor. In order to improve the reliability of the police dog identification, the chemical components of human odors have been analysed by using gas chromatography and mass spectrometry; Validation the results of instrument analysis and the police dog identification were investigated, therefore, the following research work was carried out.1. Comparative study on collecting methods of the human body odor. The seven odor collecting cloths by headspace solid phase microextraction -gas chromatography(SPME-GC) have been comparatively tested. The result indicated that the white soft cotton and degrease gauze are better than the others in absorbing human body odor and they could be used as ideal materials to collect human odor for the identification by police dog and the analysis of instrument.2. The odor copy instrument has been developed and the copied samples were tested by the identification of police dog and the analysis of gas chromatography and mass spectrometry. The result indicated that the odor copy instrument can transfer odor from the original odor location to the odor collecting cloths and the result of the odor copied by the odor copy instrument is coincident with that from the original human odor.3. The technique of SPME has been applied firstly to pretreat sample during and before analysis of human odor. The ability of various fiber coating in absorbing the human body odor were investigated. It displays that 70 m DVB and 50 m DVB/CAR/PDMS can absorb human odor properly. From the analysis of human armpit and hand by combining the solid phase microextraction and gas chromatography-mass spectrometry technique, human scent are composed of several compounds, such as fatty acid, grease, alcohol and other substances mixed as organic compounds. The odors from any people and from different parts of body such as hand or axillary have partially similarities with chemical components. It was shownthat there are 36 kinds compound of human scent by analysis of gas chromatography-mass spectrometry.4. Chromatographic fingerprint of human body odor can be set up by headspace solid phase microextraction -gas chromatography (SPME-GC).each individual has its own chromatographic fingerprints and there is highly similarities .By utilization of the pure human odor, the chromatographic fingerprints of human body odor can be used to identify and compare different human odor without knowing their chemical compounds.5. The identified results of human odor by the police dog identification and by analysis of chemical chromatographic fingerprints of human odor were compared. It was show that there are highly identical between them and they could be demonstrated each other.