Touch DNA of Shed Skin Cells from the Deployed Airbag to Address Drunken Driving Crimes

In the criminal cases of driving under the influence （DUI）, DNA evidence can be collectedfrom the deployed airbag of the motor vehicle and submitted to the crime lab for touch DNA analysis.The evidence can be acquired when the skin cells are observed on the surface of the airbag in a trafficaccident. However, the low quantity or quality of the evidence collected from a crime scene preventsfurther identification analysis in many cases. In the current study, we reported a case of identifyingtouch DNA extraction from the shed skin cells from the deployed airbag of a motor vehicle. We man-aged to collect DNA evidence from the shed skin cells in an airbag using a proper approach of collec-tion and extraction. The 5.87 ng of extracted DNA was sufficient for genotyping and forensic identifica-tion, which helped to identify the driver of the car in collision with a pier in the street. In DUI casesand other traffic accidents, therefore, the amount of touch DNA extracted from the deployed airbag canbe sufficient for DNA marker genotyping and further analysis.     

Occlusion of left and right coronary arteries and coronary sinus following blunt chest trauma

Blunt chest trauma from rapid automobile airbag deployment causing coronary artery occlusion and myocardial infarction is a rare but potentially fatal condition. We present the case of a 37-year-old man who developed extensive anterior and inferior myocardial infarction because of occlusion of both left anterior and right coronary arteries following blunt injury to the chest in a car accident. The patient was scheduled for emergency coronary angiography but left and right coronary ostia were not cannulated because of thrombus formation probably. The patient died, and the autopsy revealed external compression by epicardial hematomas involving separately left and right coronary arteries and the coronary sinus without signs of coronary and/or aortic dissection. To our knowledge, this is the first case presenting occlusion of both coronary arteries secondary to blunt chest trauma causing acute myocardial infarction in a young man without signs of prior coronary artery disease.     

Automated SEM/EDS Analysis of Airbag Residue.* I: Particle Identification

Abstract: Deployed airbags can be a valuable source of probative forensic materials. During an accident, trace evidence can be deposited on the airbag cover and in addition, the residue produced by the gas generation system is released into the passenger compartment of the vehicle as the airbag deflates. This residue can be used to associate a suspect with the vehicle at the time of the accident. This study identifies particles containing zirconium, strontium, and/or copper–cobalt along with other elements from the gas generation systems and aluminum silicon microfibers from airbag filters as the probative material which may be produced and deposited on a suspect’s hands and/or clothing. Scanning electron microscopy can be used to identify this metallic residue. Modification of the search criterion used for gunshot residue analysis allows for automated analysis of the samples. Proper collection of the airbag standard is essential to identify which materials were produced. Prompt collection of suspect samples allows the analysts the ability to make the proper identifications and associations. This analytical technique can be a probative tool in criminal investigations.     

Automated SEM/EDS Analysis of Airbag Residue. II: Airbag Residue as a Source of Percussion Primer Residue Particles

Abstract:  Automated scanning electron microscopy with energy dispersive spectroscopy has been used to analyze airbag residue particles. Analysis of airbag residue from some passenger side airbags revealed some residue particles which are consistent with gunshot residue (GSR) samples. The source of these particles was determined to be percussion primers used to initiate the chemical reaction for deployment. This article identifies some vehicles which contain this type of airbag and demonstrates the types of particles which could be misidentified as being GSR. The low numbers of GSR particles in among the large particle populations of zirconium and/or copper–cobalt particles, which are clearly airbag residue, allow the trained analysts to distinguish the correct source of this residue. Particles containing high aluminum levels, elevated levels of allowable elements in GSR particles, or the presence of elements that are rare in GSR particles stand out as indications that the particles are not GSR in origin. This study serves as a guide to analysts who perform particle analysis in forensic investigations.