Forensic Chemistry Flashcards
The art or study of formal debate; argumentation
Forensics
The use of science and technology to investigate and establish facts in criminal or civil courts of law.
Forensic Science
The branch of science which deals with the study of matter, the changes it undergoes and the energy that accompany these changes.
Chemistry
The branch of Chemistry that deals with the application of Chemical theories and principles in the solution of legal problems in connection with the administration of justice.
Forensic Chemistry
Forensic Laboratories in the Philippines
PNP Crime Laboratory
PDEA
NBI Crime Laboratory
Functions of Chemiatry
- Conduct Qualitative and Quantitative Examination of Dangerous Drugs as well as volatile substances.
- Conduct examination of explosives and/or explosive ingredients.
- Conduct examination of Firearms and Paraffin casts for the presence of Gunpowder Nitrates.
- Conduct Gunpowder examination for clothing for possible gunshot range.
- Conduct Chemical-Toxicological examination of human internal organs, gastric contents, blood water and food sample and other substances.
- Conduct examination of fake products in case of unfair trade competition.
- Conduct blood alcohol determination.
- Examine urine and other body fluids for the presence of dangerous drugs.
- Conduct researches related to the cases being examined.
- Give lectures on Forensic Chemistry & Toxicology to Police/ Military training centers, investigative units, various schools and universities.
- Testify and give expert opinion in court.
- Respond to queries of all investigative units and render expert’s opinion regarding matters related to the application of chemical principles for the purpose of assisting investigators in developing investigative leads.
- Conduct Field laboratory work and clandestine laboratory investigation.
- Perform all other official duties assigned by the Director of PNPCL and his duly authorized representatives..
Four Stages in the Practice of Forensic Chemistry
- Collection and reception of specimen –
- Actual examination.
- Report writing of the result of examination.
- Court appearance
is the proper taking, handling and packaging of specimen.
Collection
is the process of receiving the specimen by entering the condition of the sample in a log book.
Reception
Consideration in reception of sample
i. Sufficiency of sample(s)
ii. Standard for comparison
iii. Maintenance of individuality –
iv. Label and seal
all evidences should be separately wrapped to avoid contamination.
Maintenance of individuality
use for proper identification in court presentation and to avoid possibility of tampering evidences.
Label and seal
Labels should include:
the case number
name of collector
nature and source of sample date and time of collection.
Specimens brought to CL must be accompanied by a request for laboratory examination
- Addressed to D, PNPCL. Attention: C, Chemistry Div
- Nature of Case
- Specify lab exam request
- Description of the specimen.
Two Type of Examination in Forensic Chemistry
Qualitative Examination
Quantitative Examination
identification of substance present in the sample.
Qualitative examination –
determining the percent purity of the sample.
Quantitative examination –
Steps in Qualitative Exam
Physical test
Chemical (color) test.
Confirmatory test
Describing, weighing, microscopic exam
Physical Test
Simons test, Marquis test etc.
Chemical (color) test
Chromatography & Spectroscopy
Confirmatory Test
any chemical compound or mixture that, under the influence of heat, pressure, friction or shock, undergoes a sudden chemical change or decomposition
Explosives
Classification of Explosives
A.According to the velocity of reaction involved
B.According to their chemical structure
C.According to their application or design
According to velocity of reaction involved
A. High Explosives
B. Low Explosives
Speed of detonation wave is equal or greater than 1000m/s and pressure equal to thousands of atmospheres.
–Such intensity can break a material into fragments before it can move away
–Examples: TNT, RDX, PETN
High Explosives
–Rate of decomposition is relatively slow process and the wave produced is less than the speed of sound
–Applied for launching rockets, projectiles of guns and missile systems
–Example: Blackpowder
B) Low Explosives
According to their Chemical Structure
A) Organic Explosives
B) Inorganic Explosives
nitro containing organic compound. Carbo-nitro, nitrate ester, nitramines
Organic explosives
salts and other miscellaneous inorganic explosives. nitrates, nitrites, azides, halogenated amines, fulminates, chlorates, perchlorates
B) Inorganic Explosives
According to their Application or Design
A) Military Explosives
B) Industrial Explosives
–C4 – mixture of RDX, plyisobutylene, di-2ethylhexyl secabate and fuel oil
–Amatol-mixture of TNT and ammonium nitrate
–Cyclotol – RDX and TNT
–Picratol – TNT and Ammonium picrate
–Trinotal – TNT and aluminum
A) Military Explosives
–Dynamite – 75% nitroglycerine, diatomaceous earth, oxidizer
–Ammonium Nitrate explosives
–Water explosives – slurries and water gel and explosive emulsions
A)Home–made or Improvised Explosive Devices
Power source, Initiator, Explosives, and Switch
B) Industrial Explosives
The PNP Forensic Explosives Laboratory was created through the _______________ with the active support of the _________.
The support includes laboratory set-up, equipment, supplies and training packages. The laboratory was inaugurated on ________ with the Australian Ambassador to the Philippines His Excellency ________, as the guest of Honor and Speaker.
- Philippines-Australia Counter Terrorism Capacity Building Project
- Australian Federal Police
* February 01, 2007
* Tony Hely
PNP Forensic Explosives Laboratory
FUNCTIONS and CAPABILITIES
- To conduct examination of explosives on pre blast condition and residue analysis on collected specimens from a bombing incident.
- To identify what type of explosives and explosive ingredients used.
-used for physical examination of explosives and explosive ingredients in a pre-blast and post-blast investigations.
Stereo Microscope with digital camera and laptop
A powerful tool for identification of organic explosives and explosive ingredients.
Useful in detecting explosive mixtures using a sensitive separation technique and a detector.
GC-MS Agilent 6890GC-5975MS
Capable of detecting and identifying very low concentrations of organic explosives.
Main feature includes: portable and fast response and detection.
Ion Mobility Spectrometer
Ionscan 500DT
Used in the determination of anions in explosive residues.
Ex. Nitrates, Chlorates, Sulfates, Phosphates
Ion Chromatograph (Dionex ICS 2000)
IdentifyIR® is a rugged, miniaturized FT-IR (Fourier Transform Infrared) analysis system that is fast, easy-to-use, and accurate.
- can handle powders, liquids, solids, gels & pastes in both organic & aqueous solvents.
Smiths IdentifyIR
is a substance other than food intended to affect the function of the body. (Webster dictionary)
Drug