1What is forensic drug chemistry?
The scientific examination of suspected controlled substances to determine their chemical identity and, when required, their quantity or concentration.
2What is the distinction between a seized-drug analysis and a toxicological analysis?
Seized-drug analysis examines suspected substances or preparations, while toxicology examines substances or metabolites in biological specimens.
3What is a controlled substance?
A substance whose manufacture, possession, distribution, or use is regulated under applicable law.
4What Philippine law principally governs dangerous drugs and controlled precursors and essential chemicals?
Republic Act No. 9165, the Comprehensive Dangerous Drugs Act of 2002, as amended.
5What is the Dangerous Drugs Board or DDB?
The Philippine government body responsible for policy-making and strategy formulation concerning dangerous drugs prevention and control.
6What is the Philippine Drug Enforcement Agency or PDEA?
The government agency established under RA 9165 to implement and enforce dangerous drugs laws and coordinate drug law enforcement.
7What is the general chemical classification of methamphetamine?
A synthetic stimulant belonging to the substituted phenethylamine and amphetamine family.
8What is methamphetamine hydrochloride?
The hydrochloride salt form of methamphetamine, commonly encountered as a crystalline or powdered substance.
9What is the chemical distinction between methamphetamine and methamphetamine hydrochloride?
Methamphetamine is the parent compound, while methamphetamine hydrochloride is a salt containing the protonated drug and chloride counterion.
10What is the general pharmacological classification of cocaine?
A central nervous system stimulant with local anesthetic properties.
11What is the principal psychoactive compound associated with cannabis?
Delta-9-tetrahydrocannabinol, commonly abbreviated THC.
12What is cannabidiol or CBD?
A cannabinoid found in cannabis that differs pharmacologically from THC and is not generally considered intoxicating in the same manner.
13What is the general pharmacological classification of heroin?
An opioid, chemically known as diacetylmorphine.
14What is the general pharmacological classification of morphine?
An opioid analgesic.
15What is the general pharmacological classification of diazepam?
A benzodiazepine with sedative, anxiolytic, and anticonvulsant effects.
16What is the general pharmacological classification of MDMA?
A synthetic psychoactive substance with stimulant and entactogenic effects.
17What is the difference between a drug's chemical identity and its legal classification?
Chemical identity is established scientifically; legal classification depends on applicable laws and regulatory schedules.
18What is a presumptive color test for suspected drugs?
A screening reaction in which a reagent produces an observable color change that may be consistent with certain substances.
19What is the Marquis reagent traditionally used for?
Presumptive screening of certain drug classes, including some opioids and amphetamine-related substances.
20What is the Scott test commonly associated with?
Presumptive screening for cocaine using cobalt thiocyanate chemistry.
21What is the Duquenois-Levine test traditionally associated with?
Presumptive screening for cannabis-related material.
22Why are drug color tests considered presumptive rather than definitive?
Different compounds may produce similar reactions, and color observations may be affected by mixtures and other conditions.
23What is a microcrystalline test in forensic drug analysis?
A chemical examination in which a substance reacts with a reagent to produce crystals whose characteristics may assist identification.
24What is the purpose of a confirmatory drug identification method?
To provide sufficiently selective analytical evidence supporting the identity of the questioned substance.
25Why is combining independent analytical techniques useful in seized-drug identification?
Different methods provide complementary information and reduce the risk of misidentification.
26What is the role of infrared spectroscopy in seized-drug examination?
It provides molecular absorption information useful for comparing a sample with reference spectra.
27What is the role of mass spectrometry in drug identification?
It provides mass-to-charge information about ions and fragments that can assist chemical identification.
28What is a chromatographic retention time?
The elapsed time between sample introduction and detection of a component under specified chromatographic conditions.
29Can matching retention times alone conclusively identify a controlled substance?
No. Different substances may have similar retention times, so additional selective analytical information is needed.
30What is a certified drug reference standard?
A reference material with documented identity and relevant properties used to support analytical comparison or measurement.
31What is an internal standard in quantitative drug analysis?
A known substance added in a controlled amount to help account for variation in sample preparation or instrumental response.
32What is an external calibration standard?
A separately prepared reference solution used to establish an instrument response relationship for quantitative analysis.
33What is the purpose of sample homogenization before representative drug testing?
To improve uniformity so that a selected portion better represents the submitted material.
34What is a representative sample in seized-drug examination?
A portion selected using an appropriate sampling approach to provide information about the material or population being examined.
35Why is random or statistically justified sampling important when many drug packages are seized?
It helps support defensible inferences about the tested population while recognizing the sampling method's limitations.
36What is a composite sample?
A sample formed by combining portions from multiple items, potentially affecting the ability to attribute findings to individual items.
37Why should a forensic chemist avoid automatically combining all seized drug packets?
Different packets may contain different substances, and combining them can obscure item-specific findings.
38What is the distinction between net weight and gross weight of seized drug evidence?
Net weight excludes packaging or containers, while gross weight includes them.
39Why is the distinction between net and gross weight legally significant?
Statutory penalties or evidentiary determinations may depend on the legally relevant quantity of the substance rather than its packaging.
40What is drug purity in forensic chemical analysis?
The proportion of a specified drug compound within the analyzed material, expressed on a clearly defined basis.
41What is the difference between drug identification and drug purity determination?
Identification establishes what substance is present; purity determination measures how much of the material consists of that substance.
42What is a cutting agent or adulterant in a seized-drug sample?
An additional substance mixed with a drug preparation that may dilute, modify, or otherwise affect its composition.
43Why is the presence of an adulterant relevant to forensic drug examination?
It may affect analytical results, sample composition, and interpretation of the submitted material.
44What is a controlled precursor or essential chemical under drug-control legislation?
A chemical subject to regulation because of its potential use in the unlawful manufacture of dangerous drugs.
45Does the detection of a regulated precursor alone establish illegal drug manufacture?
No. Investigators must establish the legally relevant circumstances, authorization status, and supporting evidence.
46What is the purpose of an analytical drug examination certificate?
To formally report the submitted specimen, examinations performed, findings, and conclusions of the forensic laboratory.
47Scenario: A white powder gives a presumptive reaction associated with methamphetamine. What should the forensic chemist conclude?
The result is preliminary and requires suitable confirmatory analysis before reporting definitive identification.
48Scenario: Ten packets are seized, but only one packet is tested. Can the chemist automatically certify the contents of all ten?
No. Conclusions about untested packets require a scientifically defensible sampling basis and appropriately limited reporting.
49Scenario: The packaging weighs 15 grams and the contents weigh 5 grams. What is the net weight of the contents?
5 grams.
50Scenario: A chromatographic peak has the same retention time as a cocaine standard, but the mass spectrum differs. What should the examiner do?
Investigate the discrepancy and avoid identifying the substance as cocaine solely from retention time.