CH 11-12 Drugs and Forensic Toxicology

When is a substance considered a drug?

When it changes/effects you physiologically (how your body is functioning)

When is a substance a controlled substance?

When it is regulated by the government

What are the (4) main drug types?

1) Narcotics

2) Hallucinogens

3) Depressants

4) Stimulants

Narcotics are?

Pain killers (make your nervous system numb) i.e. opiates

Hallucinogens are?

Able to alter thoughts & mood (like LSD and acid)

Depressants are?

Able to slow down central nervous (alcohol & anti-anxiety)

Stimulants are?

Able to speed up central nervous system (meth/ coke/ADHD meds)

Nondrug poisons include (3)

1) Heavy metals; might contribute to natural death (arsenic)

2) Carbon monoxide; (asphyxiation) stops blood from flowing

3) Cyanide; in fungus/plant seeds

Controlled Substances Act (CSA) 1970

Classified drugs in schedules based on accepted medical use and danger of dependence (federal)

Drug Enforcement Administration (DEA)

Sets the standards of schedules

Drug dependence is either

- Psychological

- Physical

Psychological dependence

Is a conditioned use due to emotional/ social needs even habit

Physical dependence

Is the physiological need due to regular use

Withdrawal sickness

Is when administration of the drug is abruptly stopped

Drug Recognition Experts are

- Specialized police training program

- Standardized method of examining potential drug users

Schedule 1

- No current accepted medical use + high potential for abuse

- Heroin, Marijuana, Ecstasy...

Schedule 2

- High potential for abuse, potential to lead to severe psychological & physical dependence

- Cocaine, Oxycodone, Adderall...

Schedule 3

- Moderate to low potential for dependence

- Ketamine, testosterone...

Schedule 4

- Low potential for abuse / low risk of dependence

- Xanax, Valium, Tramadol...

Schedule 5

- Lower potential for abuse, generally used for antidiarrheal, antitussive, and analgesic purposes

- Lyrica...

Collection & preservation of drug evidence

- Chain of command

- Limit cross contaminants

- Packaging of evidence

Analytical methods are standardized by

- Scientific Working Group for the Analysis of Seized Drugs (SWGDRUG); sets standards internationally for accepted analytical techniques

- American Society for Testing and Materials (ASTM); reviews SWGDRUG recommendations & adopts them as protocols

* These standards keep analysis consistent across agencies & aid in admissibility

Role of a drug analyst

Identify type & amount of substance in evidence (presumptive vs confirmatory & cutting agents)

Presumptive tests

Are initial drug screenings, presence or absence, to narrow down substances

Presumptive tests include

- Color test

- Thin-Layer Chromatography (TLC); looks at rate of movement & color are analyzed, (sample is mixed w/ solvent & placed into a silica gel

- Gas chromatography (GC); separates substances based on how fast it travels

Confirmatory tests

Will quantify (confirm) what you are looking at

Confirmatory tests include

- Mass Spectrometry (MS); confirms & quantifies (GC) results by separating substances into smaller fragments based on their mass creating a unique pattern

Cutting agents

Have been added to the drug to increase the drug volume or enhance the effects

Macroscopic examination

Is just an overview (guys we're just looking at it, that's all)

Identifying Marijuana

1) Macroscopic examination

2) Microscopic examination (looking for cystolithic hairs)

3) Establish presence of psychoactive components (THC) = Duquenois - Levine Test (purple)

Identifying Mushrooms

1) Macroscopic identification

2) Establish presence of psychoactive components

- psilocin & psilocybin (other mushrooms would not have)

Synthetic drugs

Their chemical structure differs from controlled substances while retaining their physiological effects

- Bath salts (stimulants) / Fentanyl (opioid)

Clandestine drug labs

- Illegal locations that manufacture controlled substances

- Clandestine lab chemists (trained to understand what's being made + know how to clean it up)

Role of Forensic Toxicologists

Work w/ drugs after they are ingested - to determine manner of death

Drugs move in stages

1) Absorption (into bloodstream)

2) Distribution (blood through system)

3) Metabolism (body break down of drug / feel the effects)

4) Excretion (whatever is left)

Toxicology Samples include

- Blood; most used / preferred in DUI instances

- Breath; infer concentration of alcohol in bloodstream

- Hair; can give a drug timeline

- Urine; (presumptive) non-invasive / workplace & sports testing / analysis (immunoassays > measures drug concentrations using antibodies) GC / MS

Toxicological Samples that are Post-mortem

- Gastric contents; sudden death / overdose-suicide

- Vitreous humor; resistant to postmortem decay

- Bile & liver; when blood sample is limited

Challenges facing the Toxicologists

- Post mortem redistribution; concentration of a drug will not be the same

- Metabolites; Ex. Drug> heroin, Metabolite> morphine

- Toxicity varies; (toxicogenomics) genetic factors play a role in toxicity of ingested drug / poison

- Polypharmacy; take multiple drugs > makes it difficult to determine cause of death

Potential Free Response

1) What drug type does it fall under?

2) How is it made/ where does it come from?

3) What are the legal / illegal versions?

4) How does it affect the body?

PFR Opiates

1)

2)

3)

4)

PFR Amphetamines

1)

2)

3)

4)

PFR Cocaine

1)

2)

3)

4)

PFR Marijuana

1)

2)

3)

4)

PFR Ethyl Alcohol

1)

2)

3)

4)

PFR Carbon monoxide (CO)

1)

2)

3)

4)