Soil science, forensic techniques

Forensic soil science is a relatively new activity that is strongly method oriented because it is mostly a technique-driven activity in the multidisciplinary areas of pedology, geochemistry, mineralogy, molecular biology, geophysics, archaeology, and forensic science. Consequently, it does not have an overabundance of past practitioners such as in the older disciplines like physics and chemistry. 

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). 

The development of GC coupled via a combustion furnace to an IRMS (GC-C-IRMS) has allowed the analysis of individual compounds occurring at trace levels in very complex mixtures. Sometimes referred to as compound specific isotope analysis or isotope ratio monitoring MS (GC-irmMS), this technique has opened new fields of research in areas such as organic geochemistry, food science, medicine, nutrition, sport, forensic science, archaeology, soil science, and extraterrestrial science. The chromatographic separation in connection with the combustion of the analyte, however, exerts the strongest influence on the uncertainty of the measurement. Multidimensional GC (GC/GC) has also been coupled to IRMS for the authentication of flavor components. 

Analytical pyrolysis has been used successfiilly in many disciplines such as polymer chemistry, organic geochemistry, soil chemistry, forensic sciences, food science, environmental studies, microbiology, and extraterrestrial studies involving meteorites and lunar samples. A large number of organic substances found in nature are unsuitable for direct analysis by modern techniques such as column chromatography and mass spectrometry. This may be due to their complex structure and polar and nonvolatile character. 

See also Coal and Coke. Forensic Sciences Paints, Varnishes, and Lacquers. Gas Chromatography Multidimensional Techniques Instrumentation Detectors Mass Spectrometry. Geochemistry Inorganic Soil, Major Inorganic Components Soil, Minor Inorganic Components Soil, Organic Components. Laser-Based Techniques. Poiy-mers Synthetic. Quaiity Assurance Internal Standards. 

Bertino, Anthony J., and Patricia N. Bertino. Forensic Science Fundamentals and Investigations. Mason, Ohio South-Western Cengage Learning, 2009. Examines the tests and techniques used for the scientific analysis of various evidence types, including hairs and fibers, DNA, handwriting, and soil. 

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