Soil investigation, forensic

The lead contents of 206 soil samples determined by AAS indicated that such determination provides a useful parameter for soil comparison and discrimination in forensic science (Chaperlin 1981). Soil investigations near a former smelter in Colorado revealed that historic use of arsenical pesticides has contributed significantly to anthropogenic background concentrations of arsenic on certain residential properties. A variety of forensic techniques including spatial analysis, arsenic speciation and calculation of metal ratios were successful in the separation of smelter impacts from pesticide impacts (Folkes, Kuehster, and Litle 2001). 

Pye, K. and Croft, D. (2007). Forensic analysis of soil and sediment traces by scanning electron microscopy and energy-dispersive x-ray analysis An experimental investigation. Forensic Sci. Int. 165, 52-63. 

As part of a forensic investigation of a continuous Malathion spill, you need to determine the retardation coefficient of the soil at the site for Malathion. You have decided to do so in a column experiment with the soil (illustrated in Figure E6.11.1). Also given in the figure are the results of a pulse test with the nonsorptive tracer, chloride, and the results of a pulse test with Malathion. What is the retardation coefficient, R1... 

The major question posed now is how can soils be used to make accurate forensic comparisons when we know that soils are highly complex and that there are thousands of different soil types in existence For example, according to the USDA, which collects soil data at many different scales, there are more than 50,000 different varieties of soil in the United States alone. Parent material, climate, organisms, and the amount of time it takes for these properties to interact will vary worldwide. First of all, soil samples must be carefully collected and handled at the crime scene and then compared by a soil scientist with forensic science experience to ensure that the soil samples can be useful during an investigation. 

Fitzpatrick R. W Raven M and McLaughlin M. J. (2006, May). Forensic soil science An overview with reference to case investigations and challenges, in Proceedings of the First International Workshop on Criminal and Environmental Forensics (R. W. Fitzpatrick, Ed.). Perth, http //www.clw.csiro.au/cafss/. 

Hopkins, D. W Wiltshire, P. E. J., and Turner, B. D. (2000). Microbial characteristics of soils from graves An investigation at the interface of soil microbiology and forensic science. Appl. Soil Ecol. 14, 283-288. 

Carrion itself forms a lucrative substrate for invertebrate colonization however, in outdoor situations the interface between this substrate and the underlying soil, and the soil itself, also form attractive environments for certain organisms. The seepage of nutrient-rich fluids into the soil beneath the corpse significantly alters the microenvironment, affecting the inhabitant fauna. The arthropod assemblage may thus be considered to be affected by and reflective of the decomposition of the corpse and may therefore have some potential in contribution to forensic investigation (Bornemissza 1957). 

Due to their persistent silica skeletons and their diversity, diatom remains provide a good record of past and present environmental conditions. Cameron (2004) recently showed that they could be used to compare samples that had been in contact with water and for the investigation of time of death in drowning. Through the recent advances in analytical quality control and use of multivariate statistics, their use in forensics is likely to develop further. In a similar way, phytoliths (the plant opal silica structure that accumulates in some plants) have been used to differentiate soils with otherwise similar mineralogy (Marumo and Yanai 1986). 

Daugherty, L. A. (1997). Soil science contribution to an airplane crash investigation, Ruidoso, New Mexico. J. Forensic Sci. 42,401-405. 

Lerner, A., Shor, Y., Vinokurov, A., Okon, Y., and Jurkevitch, E. (2006). Can denaturing gradient gel electrophoresis (DGGE) analysis of amplified 16s rDNA of soil bacterial populations be used in forensic investigations Soil Biol. Bio-chem. 38, 1188-1192. 

Marumo, Y. and Yanai, H. (1986). Morphological analysis of opal phytoliths for soil discrimination in forensic-science investigation. J. Forensic Sci. 31,1039-1049. 

Rawlins, B. G. and Cave, M. (2004). Investigating multi-element soil geochemical signatures and their potential for use in forensic studies, in Forensic Geoscience Principles, Techniques and Applications (K. Pye and D. J. Croft, Eds.). London Geological Society Special Publication 232,197-206. 

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