1

Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

Standard Practice for the 

Collection, Preservation, 

and Analysis of Organic 

Gunshot Residues

Gunshot Residue Subcommittee 

Chemistry/Instrumental Analysis Scientific Area Committee

Organization of Scientific Area Committees (OSAC) for Forensic Science
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

Standard Practice for the Collection, Preservation, 

and Analysis of Organic Gunshot Residues

Prepared by

Gunshot Residue

Subcommittee 

Version: 1.0

May 2020

Disclaimer:

This document has been developed by the Gunshot Residue Subcommittee of the Organization 

of Scientific Area Committees (OSAC) for Forensic Science through a consensus process and 

proposed for further development through a Standard Developing Organization (SDO). This 

document is being made available so that the forensic science community and interested parties 

can consider the recommendations of the OSAC pertaining to applicable forensic science 

practices. The document was developed with input from experts in a broad array of forensic 

science disciplines as well as scientific research, measurement science, statistics, law, and 

policy.

This document has not been published by an SDO. Its contents are subject to change during the 

standards development process. All interested groups or individuals are strongly encouraged to 

submit comments on this proposed document during the open comment period administered by 

ASTM International (www.astm.org)
Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

1. Scope

1.1. This standard practice describes procedures for the sampling and preservation of organic gunshot 

residues (OGSR) recovered from hands, skin, clothing, and other substrates, also instrument 

conditions for subsequent analysis of samples by gas or liquid chromatography-mass 

spectrometry (GC-MS or LC-MS), and recommendations for reporting the significance of those 

findings.

1.2. The analysis of intact smokeless powder grains is beyond the scope of this standard practice.

1.3. OGSR originates from the combustion of the smokeless powder and the priming mixture 

following their ignition during the firearm discharge process. After a firearm has been 

discharged the combined residue can be found on exposed surfaces in the vicinity of the fired 

weapon (i.e. hands, other exposed skin surfaces, hair, clothing, and other surfaces, etc.). OGSR 

can also be found in the cartridge case after firing and can be recovered to provide information 

about the constituents of the propellant and/or priming mixture.

1.4. This standard practice discusses the collection, preservation, analysis and interpretation of 

OGSR. This standard practice does not deal with the analysis of inorganic gunshot residue 

(IGSR) or primer gunshot residue (pGSR). Individual laboratory protocol will determine if 

IGSR/pGSR and OGSR will be analyzed in a single technique or separate techniques. The 

method chosen will dictate sample collection procedures used.

1.5. Additional sources of information on forensic OGSR analysis, not specifically mentioned in the 

document, may be considered, added or substituted. A review of new sources of information on 

general forensic methods and forensic OGSR analysis should be carried out on a regular basis 

(e.g. at least annually) to incorporate well-established current findings and methods into the 

examination practices and to replace outdated methods.

1.6. This standard practice focuses on the collection, preservation and the analysis of OGSR 

components using electron ionization (EI)-GC-MS or LC-MS. However, additional analyses may 

be performed on OGSR components that have been described elsewhere [1,2].

1.7. This standard practice offers a set of instructions for performing one or more specific operations. 

This standard practice cannot replace knowledge, skill, or ability acquired through appropriate 

education, training, or experience, and should be used in conjunction with sound professional 

judgement.

1.8. Units - The values stated in SI units are to be regarded as the standard. No other units of 

measurement are included in this standard.

1.9. This standard practice does not purport to address all of the safety concerns, if any, associated 

with its use. It is the responsibility of the user of this standard to establish appropriate safety and 

health practices and determine the applicability of regulatory limitations prior to use.

2. Referenced Documents

2.1. ASTM Standards:

2.1.1 E620 Standard practice for reporting opinions of scientific or technical experts.

2.1.2 E1492 Standard practice for receiving, documenting, storing, and retrieving evidence in a 

forensic science laboratory.

2.1.3 E1588 Standard practice for gunshot residue analysis by scanning electron 

microscopy/energy dispersive X-ray spectrometry.

2.1.4 E2329 Standard practice for identification of seized drugs.
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

2.1.5 E2764 Standard practice for uncertainty assessment in the context of seized-drug analysis.

2.1.6 E2998 Standard practice for characterization and classification of smokeless powders.

2.1.7 E2999 Standard test method for analysis of organic compounds in smokeless powder by 

gas chromatography-mass spectrometry and Fourier transform infrared spectroscopy.

3. Terminology

3.1 Definitions of terms specific to this standard that are accepted based on consensus of the forensic 

community:

3.1.1 Category I, n – compounds used in the manufacture of smokeless powder or priming 

compound, and their related degradation products, which are uncommon in other 

commercial or environmental sources.

3.1.2 Category II, n – compounds used in the manufacture of smokeless powder or priming 

compounds, and their related degradation products, which are common in other commercial 

or environmental sources.

3.1.3 Characteristic residues, n. – Organic residues that have a combination of compounds rarely 

found in residues from anything other than smokeless powders.

3.1.4 Consistent residues, n. – Organic residues that have a combination of compounds that can 

be found in residues from smokeless powders but also may have othersources.

3.1.5 Double-base, n – Smokeless powder containing nitrocellulose and nitroglycerin as the 

major energetic materials.

3.1.6 Flash Suppressor, n – a chemical which, when combusted as part of a propellant mixture, 

produces gaseous products that dilutes muzzle gases and the associated flash. Flash 

suppressors are also referred to as flash inhibitors.

3.1.7 Inorganic GSR (IGSR), n – Residues from the primer, cartridge case, projectile (e.g. bullet 

or shot pellets), and/or the firearm that are primarily comprised of metal, metal oxides or 

metal salts.

3.1.8 Primer GSR (pGSR), n –Residues generating from the priming mixture that could be 

inorganic or organic in nature.

3.1.9 Plasticizer, n – Compound used to promote plasticity of a material, including flexibility, 

compressibility and reduce brittleness.

3.1.10 Organic GSR (OGSR), n – Residues from the propellant and the priming mixture that are 

organic (carbon-based) in nature.

3.1.11 Oligomer, n – A polymer whose molecule consist of relatively few repeating units.

3.1.12 SEM-EDS, n – Scanning Electron Microscope with Energy Dispersive X-ray Spectroscopy.

3.1.13 Sensitizer, n – a chemical material added with the purpose of aiding in the initiation or 

propagation of a detonation. This additive will lower the ignition temperature of the 

propellant mixture, or if added to the primer, will increase the impact sensitivity of the 

primer composition (i.e. lower energy threshold required to ignite by impact).

3.1.14 Single-base, n – Smokeless powder containing nitrocellulose as the major energetic 

material.

3.1.15 Smokeless powder, n – A propellant and low explosive composed of nitrocellulose and other 

organic and inorganic compounds.

3.1.16 Stabilizer, n – A compound or preservative used to prevent or slow down decomposition.

3.1.17 Stubbing, v – Act of pressing adhesive tape onto surface to be sampled using a collection 

stub; synonymous with dabbing or tape lift.
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

3.1.18 Triple-base, n – Smokeless powder containing nitrocellulose, nitroglycerin and 

nitroguanidine.

4. Significance and Use

4.1. Gunshot residue (GSR) examination is generally conducted to determine if an individual has 

discharged a firearm, was in close proximity to a discharged firearm, or came into contact with 

an object having gunshot residue on its surface. Traditional GSR analysis has relied upon the 

detection of inorganic GSR primarily originating from the ammunition primer (pGSR); however, 

OGSR provides information that complements pGSR analysis [1]. This standard practice is of 

use to forensic laboratories desiring to supplement pGSR analysis with OGSR analysis to 

identify surfaces exposed to gunshot residue.

4.2. This document provides a standard practice for OGSR analysis using GC-MS or LC-MS. 

Simultaneous analysis of OGSR and pGSR is outside the scope of this document. However, there 

are several papers that present a viable method for simultaneous processing and analysis [3,4]. 

Therefore, the laboratory must decide how to proceed if analyzing OGSR and/or pGSR 

separately, when only one combined sample has been received (see section 8.3.1.2 for 

recommendations provided in this practice).

5. Summary of Practice

5.1. Thisstandard practice describestechniques for collecting OGSR samplesfrom differentsubstrates, 

appropriate sample preservation techniques, and analytical procedures used to analyze OGSR. The 

interpretation and significance of these results is also addressed.

6. Apparatus

6.1. Gas chromatography-mass spectrometry (GC-MS) – a gas chromatograph (GC) that uses 

capillary columns and can be interfaced to a mass spectrometer (MS) operating in electron 

ionization (EI) mode.

6.2. Liquid chromatography-mass spectrometry (LC-MS) – a liquid chromatograph (LC) using a 

reversed phase column and pump system providing a gradient of at least two solvents (small 

column diameters, low flow rates for high sensitivity) coupled to a mass spectrometer with 

electrospray ionization (ESI) or atmospheric pressure chemical ionization (APCI) ion source 

working in positive and negative ion mode. Mass analyzers with higher resolution and mass 

accuracy, with mass measurements to the 4th decimal place, are recommended (e.g. time-offlight, triple quadrupole, etc.)

7. Materials

7.1. Solvents –LC-MS grade or a higher grade solvents (acetone, acetonitrile, ethanol, isopropanol, 

methanol, water, or other suitable solvents) should be used in all tests. Unless otherwise 

indicated, it is intended that all reagents conform to the specifications of the Committee on 

Analytical Reagents of the American Chemical Society [5]. Other grades may be used, provided 

it is first ascertained that the reagent is of sufficiently high purity without any contaminants to 

permit its use without lessening the accuracy of the determination.

7.2. Sample Collection Solvents – acetone, acetonitrile, ethanol, isopropanol or methanol or other 

appropriate solvents of LC-MS grade or equal quality are acceptable.
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

7.3. OGSR Standard(s) or Reference Materials – Certified reference materials should be purchased in 

a suitable grade, whenever possible. If an OGSR component is not available as a certified 

standard, ACS grade or higher should be purchased.

7.3.1 Appropriate concentration of individual reference materials or standards of these 

compounds may be used in addition to or instead of a reference standard.

7.4. Internal Standard – Not recommended for qualitative identification of OGSR.

7.5. GC Carrier Gas - Helium or hydrogen of purity 99.995% or higher.

8. Procedure

8.1. Collection of OGSR Samples – There are three commonly accepted sampling techniques for 

OGSR. However, each technique differs in its collection efficacy [6]. Whichever technique is 

applied, a separate sampling device should be used for each surface (e.g. left hand, right hand, 

etc.) to maximize sample recovery. [6,7]

8.1.1 Swabbing

8.1.1.1 Dry or wet swabs can be used to sample skin (e.g. hands, face, neck), surfaces, or 

objects. If wet swabbing, suitable solvents include ethanol, acetone, isopropanol or 

acetonitrile (not recommended for skin). Suitable swabs include cotton, polyester, 

muslin or nylon-based substrates [6,8]. A note of caution in choosing the solvent, the 

solvent used may dissolve other compounds that could interfere with the analysis. 

[6,7,8]

8.1.1.2 If a surface is to be stubbed for recovery of pGSR, the adhesive tape lift should be

used first and then swabbed with a suitable swab as defined above. [6]

8.1.2 Adhesive tape lifts

8.1.2.1 Adhesive tape lifts used for SEM sample stubs effectively collect OGSR from many 

surfaces, including skin, clothing and objects. Other adhesive tapes can be used at the 

discretion of the individual laboratory. [4,9]

8.1.2.2 Dab the adhesive surface of the stub onto the surface to be sampled until tackiness is 

lost to achieve maximum collection efficiency. [10]

8.1.3 Vacuuming

8.1.3.1 Vacuum lifting is appropriate for clothing or porous objects. A suitable device 

requires a vacuum fitted with an inert filter membrane with a maximum porosity of

0.5 μm to trap particulates. Teflon or fiberglass filters are suitable. [7]

8.2 Preservation of OGSR Samples

8.2.1 Samples (swabs, adhesive lifts and vacuum filters) should be stored in airtight containers 

immediately to reduce possible loss due to evaporation. Samples should be stored at 0oC 

or less to maximize preservation.[6,8]

8.3 Extraction of OGSR

8.3.1 Solvent Extractions

8.3.1.1 Swabs, filters, stubs or other adhesive lifts that have not been coated or analyzed by 

SEM-EDS, can be extracted using a suitable organic solvent, such as methanol, 

methylene chloride or acetonitrile. Extracts should be sonicated at least 5 minutes and 

then concentrated by gently evaporating with nitrogen gas to near dryness, prior to 

analysis. Extracts may be reconstituted to an appropriate volume using an organic 

solvent that is of suitable purity for GC-MS or LC-MS analysis.[7]
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

8.3.1.2 Adhesive stubs that have already been prepared and analyzed by SEM-EDS for 

pGSR, can be subsequently extracted to recover OGSR. [10]

8.3.1.3 Extraction from stubs and other adhesive lifts should be performed using either an 

20/80 ethanol: water mixture or methanol to mitigate interferents from the adhesive. 

[11]

8.4 GC-MS Analysis of OGSR Extracts

8.4.1 GC-MS analysis will identify the common organic components found in OGSR, with the 

exception of nitroguanidine and nitrocellulose, unless derivatized. [12,13,14]

8.4.2 An example of GC-MS parameters suitable for OGSR analysis is provided in Table A1.

8.4.3 Column length and temperature program conditions may be modified to specific user 

requirements, provided that each peak for a given compound of a test mixture,reference 

material, or appropriate standard is resolved.

8.4.4 Table 1 describes the target compounds that could be used to identify the presence of 

OGSR components and their key ions. For identification requirements please refer to 

section 10.1.

TABLE 1: Target Compounds for GC-MS analysis and m/z of key ions in EI MS for smokeless 

powder residues

Target Compound Significance/ Application Target Ions (m/z)

Akardite II (AK II) Stabilizer 169, 226

2-amino-4,6-dinitrotoluene (2-ADNT) Degradation products 197, 180

Dibutyl phthalate (DBP) Plasticizer 149, 223

Diisoamyl phthalate (DIP) Plasticizer 149

2,4- and 2,6-dinitrotoluene (2,4-DNT 

and 2,6-DNT)

Flash suppressor 165, 182

Dioctyl phthalate (DOP) Plasticizer 149, 279

Diphenylamine (DPA) Stabilizer 169

Ethyl centralite (EC) Stabilizer 120, 268

Ethyleneglycol dinitrate (EGDN) Explosive 46, 76

Methyl centralite (MC) Stabilizer 134, 240

2 and 4-nitrodiphenylamine (2-NDPA, 

4-NDPA)

Degradation products; 

stabilizer

167, 214

Nitroglycerin (NG) Explosive 46, 76

Nitroguanidine (NQ) Explosive 58, 104

4-nitrosodiphenylamine (4-NODPA) Degradation products 167, 198

N-nitrosodiphenlyamine (N-NODPA) Degradation product Detected as DPA

Nitrotoluenes (NTs) Sensitizer 65, 91, 120 or 137

2,4,6- trinitrotoluene (TNT) Flash suppressor/sensitizer 89, 210
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

8.5 LC-MS Analysis of OGSR Extracts

8.5.1 LC-MS analysis will identify the common organic components found in OGSR. 

Nitrocellulose is only detected in rare cases as an oligomer.

8.5.2 Only samples of appropriate dilution should be analyzed on a LC-MS system. Filtration 

or centrifugation of extracts and/or the use of a guard column isrecommended.

8.5.3 Table A2 lists example LC-MS parameters that can be used to analyze OGSR.

8.5.4 Different columns, flow rates, and solvent gradients require individual parameter 

optimization using a standard mixture for a specific LC-MS setup.

8.5.5 Table 2 describes the common target compounds that could be used to identify the 

presence of OGSR components and their key ions.

TABLE 2: Target Compounds for LC-MS analysis and m/z of key ions in MS for smokeless powder 

residues

Target Compound Mode Precursor Mass (m/z) Ionization Ref.

Nitroglycerin (NG) ESI neg., APCI

neg.

227.0026

+ adduct mass

[M+adduct]-

adduct to be 

determined by 

user

[15]

Nitrocellulose (NC); 

trimethylsilyl 

derivatized

ESI neg., APCI

neg.

481.2294 [M-H]-[13]

Diphenylamine (DPA) ESI pos. APCI pos. 170.0971 [M+H]+[4]

2 and 4-

nitrodiphenylamine 

(2-NDPA, 4-NDPA)

ESI pos. APCI pos. 215.0821 [M+H]+[4]

Nnitrosodiphenylamine 

(N-NODPA)

ESI pos. APCI pos 199.0872 [M+H]+[16]

2,4- and 2,6-

dinitrotoluene

(2,4-DNT and 2,6-

DNT)

ESI neg 181.0250 [M-H]-[4]

Methyl centralite (MC) ESI pos, APCI pos. 241.1342 [M+H]+[4]

Ethyl centralite (EC) ESI pos, APCI pos. 269.1655 [M+H]+[4]

Akardite II (AK II) ESI pos, APCI pos. 256.1087 [M+H]+[16]

9. Quality Control

9.1 Minimum quality assurance protocols

9.1.1 Establish protocol to confirm optimum instrument calibration and parameters on a routine 

basis.

9.1.2 A method blank should be prepared using the same procedure(s), reagents and conditions 

for analysis with questioned extracts.
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

9.1.3 A reference mixture of selected components listed in Tables 1 and 2, as chosen by the 

individual laboratory for the associated instrumentation, shall be analyzed with questioned 

extracts. The reference mixture must be stored in a suitable container under appropriate 

conditions. It is recommended to establish a protocol to ensure stability of the reference 

mixture and that it be replaced if degradation is suspected.

10. Data Analysis

10.1 Identification

10.1.1 The following minimum criteria must be used when making chemical compound 

identification(s): [17,18]

10.1.1.1 The analytical scheme must include at least two techniques; gas chromatographymass spectrometry or liquid chromatography-mass spectrometry.

10.1.1.2 Laboratories shall establish acceptance criteria for each technique used based upon 

validation data, and include measurement uncertainty limits if quantitative analysis is 

being performed.

10.1.1.3 The use of two techniques (e.g. GC-MS) requires that the individual acceptance 

criteria for each technique are fulfilled, separately, and the results from both are used 

in making the identification; e.g. retention time for GC and LC along with fragment 

masses for MS.

10.1.1.4 Data from a test result shall be compared to data from a reference material run 

under the same instrumental conditions.

10.2 Classification

10.2.1 The significance of compounds identified (Table 2) is based on their observed association 

with OGSR and with other environmental sources unrelated to OGSR. A classification 

scheme (Table 3) is proposed based on a review of relevant literature. [19,20,21]

TABLE 3: Classification of compounds associated with OGSR

Category Compounds Function

1 EC Stabilizer

MC Stabilizer

NG Explosive

Nitroguanidine (NQ) Explosive

2-, 4-NDPA Stabilizer

N-NODPA Degradation Product

2 NC Explosive

Other nitrotoluenes Sensitizer

DPA Stabilizer

Other DPA derivatives Stabilizer

2,4-DNT Flash Suppressor

Ak II Stabilizer

10.3 Analytical Conclusions

10.3.1 Based on the classification scheme for compounds identified (Table 3), minimum criteria 

to report OGSR has been identified are:
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

10.3.1.1 At least two category I compounds, with or without a category II compound, the 

residue is characteristic of OGSR;

10.3.1.2 One category I compound and at least one category II compound, the residue is 

consistent with OGSR.

10.3.2 If less than the minimum is identified, each compound identified may be listed but an 

inconclusive result should be reported. The reason for the inconclusive results shall be 

included for any inconclusive result.

10.3.3 If no OGSR components are detected, a negative result should be reported.

10.3.4 Additional reporting criteria with associated analytical conclusions can be developed for 

combinations not included in the previous sections. Any new criteria should aid in 

differentiating environmentally or occupationally produced residues that could be found in 

an OGSR sample. An assessment of the significance of these combinations and 

conclusions shall be made in consideration of appropriate research and documentation.

10.4 Limitations

10.4.1 Certain OGSR components can persist with time, depending on the volatility of the 

compound and adhesion or absorption by the particular substrate. [8]

10.4.2 The common mechanisms for loss of OGSR are permeation (into the skin), evaporation 

(from the skin) or physical removal (e.g. wiping, skin shedding). The extent of loss will 

vary, but generally, OGSR will persist for longer periods on porous or absorptive surfaces. 

[22]

10.4.3 Certain OGSR components can be recovered from different materials unrelated to 

firearms, such as additives (plasticizers, stabilizer) or explosives (NG and NC), and can 

also be transferred between surfaces by physical contact (i.e. secondary-transfer). [6] A 

statement to acknowledge these limitations should be included with the report or 

supplementary information appended to a report.

10.4.4 OGSR identified on one or both hands of a person sampled, cannot be used to infer if one 

or the other hand held a firearm or was used to fire a firearm.

11. Documentation

11.1Hardcopies and/or electronic format for the following must be generated and should be retained 

for an appropriate period of time as determined by the individual laboratory:

11.1.1 Instrument parameters that were used for analysis for the applicable instrument (GC-MS 

or LC-MS).

11.1.2 Documentation of calibration and tuning of the applicable instrument used for analysis 

(GC-MS or LC-MS).

11.1.3 Chromatograms, to include retention times of blank(s), reference material(s) and 

questioned samples.

11.1.4 Mass spectra of OGSR compounds identified and the associated reference material(s) used 

for comparison to identify.

11.1.5 All analytical notes from the examiner regarding OGSR analysis.

12. Keywords

12.1 OGSR; GC-MS; LC-MS
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

13. References

[1] A.L. Gassner, C. Weyermann, LC-MS method development and comparison of sampling materials 

for the analysis of organic gunshot residues, Forensic Sci Int 264 (2016), 47-55. 

10.1016/j.forsciint.2016.03.022.

[2] E. Bernal Morales, A.L. Revilla Vázquez, Simultaneous determination of inorganic and organic 

gunshot residues by capillary electrophoresis, Journal of Chromatography A 1061 (2004), 225-233. 

10.1016/j.chroma.2004.10.083.

[3] M. Morelato, A. Beavis, A. Ogle, P. Doble, P. Kirkbride, C. Roux, Screening of gunshot residues 

using desorption electrospray ionisation–mass spectrometry (DESI–MS), Forensic Science International 

217 (2012), 101-106, https://doi.org/10.1016/j.forsciint.2011.10.030.

[4] S. Benito, Z. Abrego, A. Sanchez, N. Unceta, M.A. Goicolea, R.J. Barrio, Characterization of organic 

gunshot residues in lead-free ammunition using a new sample collection device for liquid 

chromatography-quadrupole time-of-flight mass spectrometry, Forensic Sci Int 246 (2015), 79-85. 

10.1016/j.forsciint.2014.11.002.

[5] R.M. Martz, L.D. Lasswell In Identification of smokeless powders and their residues by capillary 

column gas chromatography/mass spectrometry, Proceedings of the International Symposium on the 

Analysis and Detection of Explosives, Quantico, VA: FBI Academy, 1983 March 29-31; Quantico, VA: 

FBI Academy, 1983; pp 245-254.

[6] A.L. Gassner, C. Ribeiro, J. Kobylinska, A. Zeichner, C. Weyermann, Organic gunshot residues: 

Observations about sampling and transfer mechanisms, Forensic Sci Int 266 (2016), 369-78. 

10.1016/j.forsciint.2016.06.029.

[7] E. Goudsmits, G.P. Sharples, J.W. Birkett, Recent trends in organic gunshot residue analysis, TrAC 

Trends in Analytical Chemistry 74 (2015), 46-57. 10.1016/j.trac.2015.05.010.

[8] J.D. Ropero-Miller, J.S. Morgan, S. Bell, Organic Gunshot Residue Analysis for PotentialShooter 

Determination. National Institute of Justice: Forensic Technology Center of Excellence, 2015; p 17.

[9] R. Schumacher, M. Barth, D. Neimke, L. Niewöhner, Investigation of gunshot residue patterns using 

milli-XRF-techniques: first experiences in casework. 2010.

[10] A. Zeichner, N. Levin, Collection Efficiency of Gunshot Residue (GSR) Particles from Hair and 

Hands Using Double-Side Adhesive Tape, Journal of Forensic Science 38 (1993), 571-584.

[11] A. Zeichner, B. Eldar, A Novel Method for Extraction and Analysis of Gunpowder Residues on 

Double-Side Adhesive Coated Stubs, Journal of Forensic Sciences 49 (2004), 1194-206.
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

[12] A. Voloshenko Rossin, S. Sladkevich, G. Gasser, A. Melman, O. Lev, Sensitive Analysisof 

Nitroguanidine in Aqueous and Soil Matrices by LC-MS, Anal Chem 89 (2017), 9990-9996. 

10.1021/acs.analchem.7b02364.

[13] A.S. Chajistamatiou, E.B. Bakeas, A rapid method for the identification of nitrocellulose in high 

explosives and smokeless powders using GC-EI-MS, Talanta 151 (2016), 192-201. 

10.1016/j.talanta.2016.01.038.

[14] American Society for Testing and Materials, E2999 - Standard Test Method for Analysis ofOrganic 

Compounds in Smokeless Powder by Gas Chromatography-Mass Spectrometry and Fourier Transform 

Infrared Spectroscopy. 2017.

[15] J.L. Thomas, D. Lincoln, B.R. McCord, Separation and detection of smokeless powder additives by 

ultra performance liquid chromatography with tandem mass spectrometry (UPLC/MS/MS), Journal of 

Forensic Science 58 (2013), 609-15. 10.1111/1556-4029.12096.

[16] D. Laza, B. Nys, J.D. Kinder, A. Kirsch-De Mesmaeker, C. Moucheron, Development of a 

quantitative LC-MS/MS method for the analysis of common propellant powder stabilizers in gunshot 

residue, J Forensic Sci 52 (2007), 842-50. 10.1111/j.1556-4029.2007.00490.x.

[17] American Societyfor Testing and Materials, E2329 - Standard Practice for Identification of Seized 

Drugs. 2017.

[18] American Society for Testing and Materials, E2764 - Standard Practice for Uncertainty Assessment 

in the Context of Seized-Drug Analysis. 2011.

[19] E. Goudsmits, G.P. Sharples, J.W. Birkett, Preliminary classification of characteristicorganic 

gunshot residue compounds, Sci Justice 56 (2016), 421-425. 10.1016/j.scijus.2016.06.007.

[20] M. Manganelli, C. Weyermann, A.L. Gassner, Surveys of organic gunshot residueprevalence: 

Comparison between civilian and police populations, Forensic Sci Int 298 (2019), 48-57. 

10.1016/j.forsciint.2019.02.050.

[21] J. Arndt, S. Bell, L. Crookshanks, M. Lovejoy, C. Oleska, T. Tulley, D. Wolfe, Preliminary 

evaluation of the persistence of organic gunshot residue, Forensic Science International 222 (2012), 137-

145. https://doi.org/10.1016/j.forsciint.2012.05.011.

[22] C. Hofstetter, M. Maitre, A. Beavis, C.P. Roux, C. Weyermann, A.L. Gassner, A study of transfer 

and prevalence of organic gunshot residues, Forensic Sci Int 277 (2017), 241-251. 

10.1016/j.forsciint.2017.06.013.
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Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

ANNEX

(Mandatory Information)

A1. INSTRUMENTAL OPERATION PARAMETERS

A1.1 GC-MS parameters example

A1.1.1 An example GC-MS instrumental method, from literature, to analyze OGSR compounds is 

provided below as a starting point for the laboratory validation process.

TABLE A1: Recommended GC-MS conditions [14]

Parameter Condition

GC column: 30 meter, DB-5

Injector Temp: 180° C

Initial Temp (T0): 40-50° C

Hold time (T0): 3 minutes

Ramp 1: 15° C/minute to 150° C (T1)

Hold time (T1): 2 minutes

Ramp 2: 20-40° C/minute to 265° C (T2)

Hold time (T2): 8 minutes

Mode: EI

Scan Mode Full Scan or Selected Ion Monitoring

Split Ratio: Splitless (n/a)

MS range: 40 to 500 m/z

Source Temp: 230° C

Solvent delay: 3 minutes

A1.2 Recommended LC-MS Parameters

A1.2.1 An example LC-MS instrumental method, from literature, to analyzed OGSR compounds

is provided below as a starting point for the laboratory validation process. This method 

uses a quadrupole-time of flight mass spectrometry (qTOFMS); however, this method can 

be modified for any mass spectrometer system.

TABLE A2: Recommended LC-MS conditions [4]

Parameter Condition (APCI) Condition (ESI)

LC column C18 column: 100 mm × 3 

mm, 2.6 m

C8 column: 2.1 × 150 mm, 5

m

C18 column: 100 mm × 3 

mm, 2.6 m

C8 column: 2.1 × 150 mm, 5

m
12

Standard Practice for the Collection, Preservation, and Analysis

of Organic Gunshot Residue

Column Temperature 40 ± 5 oC 40 ± 5 oC

Elution Gradient 

Solvent A

Solvent B

Ammonium acetate 1 mM 

Methanol

Ammonium acetate 1 mM 

Methanol

Injection Amount 5 L 5 L

Needle Rinse 90 s with methanol 90 s with methanol

MS Ionization Interface APCI ESI

Ionization Gas Dichloromethane Dichloromethane

Dry Gas Flow 15 L/min 10 L/min

Dry Gas Temperature 300 oC 300 oC

Nebulizer Pressure 30 psi 30 psi

Sheath Gas Temperature 300 oC 300 oC

Ionization Mode Positive and Negative 

applied alternatively,

Positive, or Negative

Positive and Negative 

applied alternatively,

Positive, or Negative