BIBLIOGRAPHY:CONCLUSIONS:

Self-defense weapons based on Riot Control Agents (RCA) (like lachrymators) are worldwide used, but its use is are limited by national legislation. In Portugal self-defense aerosols can only use the active principle (RCA)Capsaicin or Oleoresin Capsicum (OC; extraction product from peppers and similar species) in a concentration lower than 5 (w/v) %. The juridical consequences of using illegal self-defense weapons demand the use ofvalidated analytical methods and the assessment of the weapons compliance with legislation considering the reliability of measurements. In Portugal, these evaluations are performed in the Scientific Police Laboratoryfrom Polícia Judiciária, in a two steps metrological procedure, divided on a qualitative (active principle identification) and quantitative analysis. The quantitative evaluation is further divided in two stages: a semi-quantitative (single-point calibration) and a quantitative analysis (multi-point calibration).

ACKNOWLEDGEMENTS:

To the Biotoxicology Area Direction of the Scientific PoliceLaboratory of Polícia Judiciária (Dr. Sandra Santos and Dr. JoanaAlegre).

LABORATÓRIO DE POLÍCIA CIENTÍFICA

Área de BiotoxicologiaQUÍMICA LABORATORIAL

Reilly, C.A.; Crouch, D.J.; Yost, G.S.; “Quantitative Anaylsis ofCapsaicinoids in Fresh Peppers, Oleoresin Capsicum and PepperSpray Products”, J Forensic Sci., 2001, 46 (3), 502-9. Haas, J.S.; Whipple, R.E.; Grant, P.M.; Andresen, B.D.; Volpe, A.M.;

Pelkey, G.E.; “Chemical and elemental comparison of twoformulation of oleoresin capsicum”, Sci Justice., 1997, 37(1), 15-24.Eurachem Working Group, Eurachem Guide - The Fitness for

Purpose of Analytical Methods, 1998.

Tetracosane Solvent (Chloroform : Mehtanol(1:1))

Mixture 1 Preparation (1012

mg L-1 of tetracosane)

Sample Dilution(V1 + V2) – 400 mg L-1

of tetracosane GC-MS Analysis

Capsaicin Stock Solution Preparation

Capsaicin Calibration Standards Preparation:A capsaicin stock solution aliquot and 400 μL of tetracosane stock solution (internal standard) were diluted with chloroform:metanol

(1:1) to a final volume of 1 mL using a volumetric flask.

0,15 % 0,20 % 0,25 % 0,30 % 0,35 %Capsaicin Concentration Calibration

Deviation

(First)Single-point

Standard Analysis

Sample Analysis(Replicated)

(Second)Single-point

Standard Analysis

SampleResults(Single)

Legal

Multi-pointCalibration

Curve

SampleResults(Multi)

Illegal

Qualitative Analysis criteria

Acceptation criteria for single-point standard (First)

Acceptation criteria for sample replicates

Acceptation criteria for single-point

standards(repeatability)

Decision criteria for single-point calibration

Acceptation criteria for multi-point

calibration

Decision criteria for multi-point calibration

rTr

R

stT

stR

•Chromatographic Area Ratio (R1)

•Retention Time (Tr1)(Capsaicin)

rTrrSr sTT 231

•Chromatographic Area Ratio (RS)

•Retention Time (TrS)(Capsaicin)

rTrrr

rR

sTT

sRR

23

23

21

21

•Chromatographic Area Ratio (R2)

•Retention Time (Tr2)(Capsaicin)

•Single-point Capsaicin

Concentration (Ccaps-SP)

If

99,0rrTrrSr sTT 234

•Retention Time of standard 2500 mgL-1(Tr3)

Then the self-defense weapon is legal

Then quantification is required (Mutli-point calibration)

•Single-point calibration uncertainty

(ucaps-SP)

≥ 5 %< 5 % < 5 %

•Multi-point Capsaicin

Concentration (Ccaps-MP)

•Multi-point calibration uncertainty (ucaps-MP)

Unknown constitution self-defense weapon

Qualitative Sample

Preparation (Extraction)

Illegal

Quantitative Sample

Preparation

Qualitative Analysis GC-MS

LegalSingle-Point

Calibration

Multi-Point

CalibrationNo Capsaicin or

Oleoresin

Capsicum

Capsaicin or Oleoresin

Capsicum

Lower 5 %

Above or Closer to

5 %

Above 5 %

Lower 5 %

Quantitative Analysis

≥ 5 %

No Capsaicin

or OC

Capsaicin or OC

Criterion Interval for Area Ratio of single-

point standard

Criterion interval for Retention Time of

single-point standard (Capsaicin)

Criterion Interval for Retention Time of sample replicates

(Capsaicin)

Criterion Interval for Area Ratio of single-

point standard replicates

Criterion Interval for Retention Time of

single-point standard replicates

Calibration Curve Linearity

Criterion Interval for Retention Time of samples(Capsaicin)

If

The self-defense weapon is legal%52 MPcapsMPcaps uC

The self-defense weapon is illegal

%52 MPcapsMPcaps uC

Or

%52 SPcapsSPcaps uC

Or

%52 SPcapsSPcaps uC

22

33

332

QPCSCCCS CC

QPCSCCCS

uu

CC

Calibration Curve Control – Standard 3

•Concentration and uncertainties for

standard 3 (CC and QP)

Daniel M. Silveiraa,b, Pedro A. S. Salgueiroa,

Ricardo J. N. Bettencourt da Silvab, M. Filomena G. F. C. Camõesb

a Laboratório de Polícia Científica, PJ, 1169-007 Lisboa, Portugal; email –daniel.msfc@gmail.com

b CCMM - Departamento de Química e Bioquímica, FCUL, Campo Grande, 1749-016 Lisboa, Portugal

The developed analytical method and metrological models allowthe reliable identification of the active principles in self-defenseweapons and the quantification of capsaicin in it.This was accomplished by a detailed method validation, thatallowed the determination of used quantitative and qualitativemetrological criteria.

total

Stddilstdsolerimpur

m

fffVCw ..intint

It was used a highly pure capsaicin to determinate the purity of other standard.

(Im)Purity (in mass fraction)

Cause-and-effect diagram is similar to multi-point

calibration

Capsaicin Solid

Standard

Low purity standard (0,25 %)

High purity calibration curve

Purity / Traceability

Cinterpolation

Ccapsaicin

Instrumental Quantification

fdil

Vsample

Rep.

Tol.

Rep.

Vmixture 1

Tol.

fstd

Vsolution mcapsaicin

Rep. Rep.Tol. Cal.

Purity

fint. std

Cint. std.

(CalibrationCurve)

mint. stdVsolution

Cint. std.

(Sample)Vsolutionmint. std

Instrumental Repeatability

Signalcapsaicin

Signalint. std

Ccapsaicin

fdil

Single-pointStandard Solution

mcapsaicin

CalibrationDeviation

Vsolution

Rep.

Tol.

Rep.

Cal.Instrumental Repeatability

Vsample

Rep.

Tol.Rep.

Vmixture 1

Tol.

Purity

Signalcapsaicin

Signalint. std

fint. std

Cint. std.

(CalibrationCurve)

mint. stdVsolution

Cint. std.

(Sample)Vsolutionmint. std

Signal(Std)

ConcentrationStd

Signal(Y)

Concentration (x)