DeHaan John D, Taormina Eimi I, Brien David J
Fire-Ex Forensics, 3505 Sonoma Blvd, Ste. 20-314, Vallejo, CA 94590, USA.
Forensic Science Graduate Program, University of California, Davis, One Shields Avenue, Davis, CA 95616, USA.
Sci Justice. 2017 Mar;57(2):118-127. doi: 10.1016/j.scijus.2016.12.002. Epub 2016 Dec 23.
Debris collected from various test sites where mammalian remains (human and porcine) had been burned in a variety of full-scale fire scenarios was evaluated for the presence of volatile residues that could be characteristic of those remains. Levels of volatiles were measured using the method commonly used for fire debris analysis: gas chromatography-mass spectrometry. Homologous n-aldehydes (from n-pentanal to n-nonanal) proved to be a significant indicator of the presence of burned animal tissue as they were observed in nearly all of the samples. Such aldehydes are created by the combustion of animal fats. One aldehyde, n-hexanal, appeared more frequently than the other aldehydes, n-pentanal, n-heptanal, n-octanal, and n-nonanal. Ethanol was detected in two-thirds of the samples, while acetone appeared in about three-fourths of the samples, but both were detected at much lower concentrations than n-hexanal. These appear to have been combustion products of the substrates on which each body burned, rather than originating from the combustion of the body. There appeared to be no qualitative distinction between volatile products produced from burned porcine carcasses and those from human cadavers. Since a homologous series of C-Cn-aldehydes is not produced as a dominant species by the pyrolysis or combustion of any normally encountered substrate (carpet, bedding, wood products or upholstery), their detection by normal fire debris methods appears to be a valid indicator of the presence of burned animal remains. These data will also provide guidance to fire debris analysts as to the nature of volatiles associated with the combustion of human bodies in real-world fires.
从各种测试地点收集的碎片进行了评估,这些测试地点在各种全尺寸火灾场景中焚烧了哺乳动物遗体(人类和猪),以检测是否存在可能是这些遗体特征的挥发性残留物。使用火灾碎片分析常用的方法——气相色谱-质谱法来测量挥发性物质的含量。同系正构醛(从正戊醛到正壬醛)被证明是燃烧动物组织存在的重要指标,因为几乎在所有样品中都观察到了它们。这些醛是由动物脂肪燃烧产生的。一种醛,正己醛,比其他醛,正戊醛、正庚醛、正辛醛和正壬醛出现得更频繁。三分之二的样品中检测到了乙醇,约四分之三的样品中出现了丙酮,但两者的检测浓度都远低于正己醛。这些似乎是每个尸体燃烧所依托的底物的燃烧产物,而不是源于尸体的燃烧。燃烧猪尸体产生的挥发性产物与燃烧人类尸体产生的挥发性产物之间似乎没有定性区别。由于任何常见底物(地毯、床上用品、木制品或室内装潢)的热解或燃烧都不会产生同系的C-Cn醛作为主要成分,因此通过常规火灾碎片方法检测到它们似乎是燃烧动物遗体存在的有效指标。这些数据也将为火灾碎片分析师提供有关现实火灾中与人体燃烧相关的挥发性物质性质的指导。