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
is a substance in certain doses which when taken into the human body cures illness and/or relieves signs/symptoms of disease
Medicine
Dangerous Drugs - any substance classified under RA 9165.
Stimulants
•Depressants
•Hallucinogens
•Designer drugs
Drug Abused in the Philippines
Shabu - methamphetamine hydrochloride
Marijuana - tetrahydrocannabinol
Ecstasy - Methylene dioxy methamphetamine
• These drugs are used to increase mental activity, relieve fatigue and offset drowsiness.
Stimulant
Can cause mental retardation to unborn babies
•Extended wakefulness and increased mental alertness
•Loss of memory
•Irritability, anxiety and fear
•Lacks interest towards studies and work
•Chronic snorters suffer from irritation of the nose to frequent nose bleeding
•Loss of appetite resulting in decreased body weights
Stimulant
Examples of Stimulant
Cocaine Methylamphetamine Hydrochloride (shabu) Bangkok Pills (phentermine)
– plant source of shabu
Ephedra plant (Ma Huang)
Methylamphetamine Originally synthesized from Ephedrine in Japan by ______ (1888).
Dr Nagayoshi Nagai
The word “coca” is a pre-Incan Tiwanaku word ____ means “the plant”
Chewed to produce mild and long lasting euphoria
Khoka
Other term for cocaine
coke, crank, snow, crack (crystalline free-base form), zip
Cocaine, Originated from ___________ (Found in S America & Java)
Used as a Local anesthetic in minor surgery.
Most Potent natural stimulant
Some users combine cocaine powder or crack with heroin in a “speedball.“
Erytroxylon coca
Substances that depress the function of the central nervous system of the body.
Depressants
Example of depressant
Example: Sedative and hypnotic
Common name: “yellow jackets”, “blue devils”, rainbow, Amy’s and “reds” (stem from the color of the capsule or tablet).
Barbiturates (sleeping pills)
The agent that cause Marilyn Monroe’s death
Barbiturates
First synthesize (1863) by ________ (German Chemist).
The word “barbiturate” is a combination of “Barbara” with “urea”:
von Baeyer discovered it on Saint Barbara’s Day, and urea
was used in the synthesis
of the new molecule.
Barbara + Urea
Adolf von Baeyer
Types of Depressants
Barbiturates (sleeping pills)
Tranquilizer (Benzodiazepam)
Two types of tranquilizer
2 Types:
Major Tranquilizer and
Minor Tranquilizer
Examples of tranquilizer
Examples: Rohypnol and valium
Has replaced many of the barbiturates. However, barbiturates are still used to treat some types of epilepsy.
“benzodiazepines”
Benzodiazepines Combining with _____ (in substantial amount) can lead to coma or even death.
alcohol
Benzodiazepines Tolerance can cause physical dependence, with typical withdrawal symptoms ranging from _______ when the drug intake is stopped.
nightmares to convulsions
- used to eliminate pain.
Narcotics
Example of Narcotics
Example: opium, morphine, heroin
- Slows down and in some cases, stops breathing.
- Nausea and vomiting.
- Constipation
- Lowers testosterone level.
- The use of needles for drug injection provides an entryway for many kinds of infections.
EFFECTS of Narcotics
are drugs that can produce changes in mood and behavior and can produce delusions and hallucinations.
A user may speak of “hearing” colors, and “seeing” sounds.
Hallucinogens
Examples of hallucinogen
Example: Mariuana, Phencyclidine, Lysergic Acid Diethylamine (LSD)
History: Began in the early 1960’s when teenagers found that inhaling the fumes from model airplane glue produced a “high.”
Inhalants
Example of inhalant
Rugby, thinner, solvent, gasoline, and other gasoline-based products, kerosine, nail polish, cuticle remover, lighter fluid, and dry-cleaning fluid
Is there a case where a person died because of sniffing glue?
Yes! One case in 1960’s which involved a 19-year-old man who suffocated in his bathroom while sniffing glue. Had a history of glue sniffing and had been treated for a liver problem brought on by the sniffing when he was 12-years-old.
Classifications of Drugs
Stimulants Depressants Narcotics - not included in the list of RA 9165 Hallucinogens Inhalants
A person apprehended or arrested who is found to be POSITIVE for dangerous drug after confirmatory exam
Penalty
•First offense: Min of 6 months rehabilitation
•Second offense: imprisonment from 6 years and 1 day to 12 years and fine of P50T to P200T.
Sec 15 of RA 9165: Use of Dangerous Drugs
A penalty of life imprisonment to death and fine ranging from P500T to P10M shall be imposed to any person, unless authorized by law, who posses any dangerous drug in the following quantity:
II. Sec 11 of RA 9165: Possession of Dangerous Drugs
50 grams or more of shabu
500 grams or more of MJ
10 grams or more of opium, morphine, heroin, cocaine and salt, Marijuana resin and oil, ecstacy.
II. Sec 11 of RA 9165: Possession of Dangerous Drugs
A penalty of life imprisonment to death and fine ranging from P500T to P10M shall be imposed to any person, unless authorized by law, shall engage in manufacture of dangerous drugs.
A penalty of imprisonment from 12 yrs and 1 day to 20 yrs and fine ranging from P100T to P500T shall be imposed to any person, unless authorized by law, shall engage in manufacture of controlled precursor and essential chemicals.
Sec 8 of RA 9165: Manufacture of Dangerous Drugs
SOP in Seized Drug Exam
- Receiving
- Examination
- Evidence storage
- Retrieval of Lab report by requesting party
- Retrieval of report and evidence for court presentation.
- Disposal
It is the determination of the presence of dangerous drugs in human body fluids (urine, blood, sweat, saliva) and hair
Government and private drug testing laboratory (Ownership)
Drug testing
Importance of Drug Testing:
A. Medical – to monitor a patient’s progress in medical treatment program for a drug abuse problem acknowledged by the patient.
B. Legal – to determine if the suspect had taken controlled substances prior to an accident or crime.
C. Medico-legal – in an employer’s drug abuse program aimed at both preventing drug related accidents & crimes and identifying & treating employees w/ drug abuse problems.
Mandatory Drug Testing
- Drivers and firearms license
- military and law enforcers
- candidate for public office and
- persons apprehended under RA 9165
Legal Aspect
•Comprehensive dangerous drug Act of 2002
•First offense: ______
•Second offense: 6 to 12 years imprisonment and fine of 100 to 500T.
•Validity of result: _______
min of 6 months rehab
1 year after issuance
Factor Affecting the Presence of Drugs in the Body:
- Type of drugs & its clearance rate in urine
- Frequency of Intake
- Metabolic Rate
- Route of Administration
Drug test
Two (2) stages of examination
- Screening using test kits
2. Confirmatory
Confirmatory Test
a) Thin Layer Chromatography
b) Instrumentation-Gas Chromatography Mass Spectroscopy (GCMS) machine
a white, translucent, tasteless, odorless solid consisting of a mixture of solid hydrocarbons of high molecular weight.
Paraffin Wax –
Principle
•Gunpowder basically has ________ as its main ingredient. So that when a gun is fired, one will expect to find ______ in the barrel of the gun, in and around the wound and clothing of the person fired upon at close range.
2KNO3 + 3C + S - - - - >3CO2 + K2S + N2
nitrates
NITRATES
Some of these burned and partially burned particles may escape around the _____ of the gun and become implanted on the exposed surface of the _____ of the person firing the gun.
•The presence of these particles serve as the basis of the paraffin test.
breech
hand
It is possible to detect nitrates as late as ______ even if the hands have been washed.
3 days (or 72 hours)
History of Paraffin Test
•The paraffin test originated from ___ when ____________ first used paraffin for the purpose of collecting residues from discharged firearm. This technique was improved by ____________of Criminal Identification Lab in _____ and was introduced in the US in 1933.
Cuba
Dr Gonzalo Iturrios
Mr. Teodoro Gonzales
Mexico
Procedure
•The hands of the subject are washed under running water and air-dried.
•His hands are placed on top a clean sheet of paper.
•____________is dropped on the dorsal portion of the hands.
•When the surface is covered by a thick coating of paraffin, a layer of clean _______ is placed over the paraffin.
The cotton layer is again coated with paraffin.
•After the paraffin casts have set and cooled, these are gently lifted and both hands are removed.
•The casts are treated with ________ reagent.
•______________ develop when nitrates come in contact with DPA.
Molten paraffin (38-40 deg C)
gauze or cotton
Diphenylamine (DPA)
Deep blue specks with tailings
Will other nitrate-containing compounds yield positive result?
•If the hands are contaminated with other nitrate-containing compounds one will expect to find _______ color or a conglomeration blue specks at different places of the hands.
•Nitrate-containing contaminants are dealt with during the ____
smudges or just a smear of blue
washing of hands.
Is the result of paraffin test conclusive?
•Paraffin test can be used as a ________ evidence.
•A negative result does not mean the subject did not fire a gun because there are factors that affect the presence of gunpowder residues.
corroborative
The factors that affects the presence of gunpowder
What are these factors? •Type of caliber of ammunition •Length of barrel •Wind direction and velocity •Age/efficiency of mechanism of gun •Direction of firing •Humidity/percent moisture in air
Type of caliber
•A hand firing a _____ is more likely to yield a positive result for gunpowder nitrates compared to a and firing a pistol.
revolver
Length of barrel
•In a longer barrel the hand is farther away from the muzzle end of the gun.
•According to literature, a weapon of 2-inch barrel will deposit residue ____ a larger area than will a weapon of 5-inch barrel (even if they are fired from the same distance with the same type of ammunition).
over
Wind direction and velocity
•In high wind velocity, the powder residues will be blown in the direction of the wind.
•One is more likely to be positive for gunpowder nitrates if there is no wind, or when the direction of the wind is _______ from the body.
away
is more likely to occur in a new weapon compared to an old one.
Complete combustion
Is more likely to happen in an old weapon where the breech mechanism is no longer tightly fitted.
Leakage of gunpowder
It is more probable that a person firing the gun in upward position would end up ______ compared to a downward firing of the gun.
positive
_______ lessens the extent of combustion yielding more gunpowder nitrates.
Humidity
Are there methods other than paraffin test?
•Instrumental analysis for the presence of _______,______,______, which are most inorganic components of firearm ammunitions.
Scanning Electron Microscope (SEM)
Atomic Absorption Spectroscopy (AAS)
lead, antimony and barium
“If the law has made you a witness, remain a man of science.
You have no victim to avenge, no guilty or innocent person to ruin
or save — you must bear testimony within the limits of science.”’
— Dr. P.C.H. Brouardel
19th Century French Medico-legalist
