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Trends in composition, collection, persistence, and analysis of IGSR and OGSR: A review

NCJ Number
Forensic Chemistry Volume: 19 Dated: June 2020
Date Published
June 2020
16 pages

This study reviewed scientific literature from the past two decades on the various factors that affect the deposition, persistence, and collection of organic and inorganic gunshot residue (OGSR and IGSR, respectively).


Market changes in the manufacture of modern ammunition have affected typical elemental composition and morphology of particles, along with complex transfer and persistence mechanisms. This has prompted the forensic community to investigate means for a more comprehensive approach that incorporates IGSR and OGSR detection. Once collected, inorganic components are more persistent over time than OGSR. Conversely, exogenous compounds that mimic OGSR markers are less prevalent in the environment than IGSR-like elements. As a result, the combined detection of IGSR and OGSR is expected to decrease the occurrence of false positives and false negatives and bring superior confidence in the interpretation of results. This review also compiled information on over 180 primary IGSR and OGSR components reported in the literature for modern ammunition (standard and non-toxic) and their respective analyses. Also, this review offers a discussion of the capabilities and limitations of novel methods and future opportunities to adopt changes in the management of forensic investigations to improve the versatility, reliability, and response time in the discipline. (publisher abstract modified)

Date Published: June 1, 2020